Commit graph

21067 commits

Author SHA1 Message Date
Alexei Starovoitov
687f07156b bpf: fix out of bounds access in verifier log
when the verifier log is enabled the print_bpf_insn() is doing
bpf_alu_string[BPF_OP(insn->code) >> 4]
and
bpf_jmp_string[BPF_OP(insn->code) >> 4]
where BPF_OP is a 4-bit instruction opcode.
Malformed insns can cause out of bounds access.
Fix it by sizing arrays appropriately.

The bug was found by clang address sanitizer with libfuzzer.

Reported-by: Yonghong Song <yhs@plumgrid.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-09 14:11:55 -07:00
Daniel Borkmann
592867bfab ebpf: fix fd refcount leaks related to maps in bpf syscall
We may already have gotten a proper fd struct through fdget(), so
whenever we return at the end of an map operation, we need to call
fdput(). However, each map operation from syscall side first probes
CHECK_ATTR() to verify that unused fields in the bpf_attr union are
zero.

In case of malformed input, we return with error, but the lookup to
the map_fd was already performed at that time, so that we return
without an corresponding fdput(). Fix it by performing an fdget()
only right before bpf_map_get(). The fdget() invocation on maps in
the verifier is not affected.

Fixes: db20fd2b01 ("bpf: add lookup/update/delete/iterate methods to BPF maps")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-09 12:39:34 -07:00
Linus Torvalds
f6f7a63692 Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton:
 "Almost all of the rest of MM.  There was an unusually large amount of
  MM material this time"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (141 commits)
  zpool: remove no-op module init/exit
  mm: zbud: constify the zbud_ops
  mm: zpool: constify the zpool_ops
  mm: swap: zswap: maybe_preload & refactoring
  zram: unify error reporting
  zsmalloc: remove null check from destroy_handle_cache()
  zsmalloc: do not take class lock in zs_shrinker_count()
  zsmalloc: use class->pages_per_zspage
  zsmalloc: consider ZS_ALMOST_FULL as migrate source
  zsmalloc: partial page ordering within a fullness_list
  zsmalloc: use shrinker to trigger auto-compaction
  zsmalloc: account the number of compacted pages
  zsmalloc/zram: introduce zs_pool_stats api
  zsmalloc: cosmetic compaction code adjustments
  zsmalloc: introduce zs_can_compact() function
  zsmalloc: always keep per-class stats
  zsmalloc: drop unused variable `nr_to_migrate'
  mm/memblock.c: fix comment in __next_mem_range()
  mm/page_alloc.c: fix type information of memoryless node
  memory-hotplug: fix comments in zone_spanned_pages_in_node() and zone_spanned_pages_in_node()
  ...
2015-09-08 17:52:23 -07:00
Vlastimil Babka
96db800f5d mm: rename alloc_pages_exact_node() to __alloc_pages_node()
alloc_pages_exact_node() was introduced in commit 6484eb3e2a ("page
allocator: do not check NUMA node ID when the caller knows the node is
valid") as an optimized variant of alloc_pages_node(), that doesn't
fallback to current node for nid == NUMA_NO_NODE.  Unfortunately the
name of the function can easily suggest that the allocation is
restricted to the given node and fails otherwise.  In truth, the node is
only preferred, unless __GFP_THISNODE is passed among the gfp flags.

The misleading name has lead to mistakes in the past, see for example
commits 5265047ac3 ("mm, thp: really limit transparent hugepage
allocation to local node") and b360edb43f ("mm, mempolicy:
migrate_to_node should only migrate to node").

Another issue with the name is that there's a family of
alloc_pages_exact*() functions where 'exact' means exact size (instead
of page order), which leads to more confusion.

To prevent further mistakes, this patch effectively renames
alloc_pages_exact_node() to __alloc_pages_node() to better convey that
it's an optimized variant of alloc_pages_node() not intended for general
usage.  Both functions get described in comments.

It has been also considered to really provide a convenience function for
allocations restricted to a node, but the major opinion seems to be that
__GFP_THISNODE already provides that functionality and we shouldn't
duplicate the API needlessly.  The number of users would be small
anyway.

Existing callers of alloc_pages_exact_node() are simply converted to
call __alloc_pages_node(), with the exception of sba_alloc_coherent()
which open-codes the check for NUMA_NO_NODE, so it is converted to use
alloc_pages_node() instead.  This means it no longer performs some
VM_BUG_ON checks, and since the current check for nid in
alloc_pages_node() uses a 'nid < 0' comparison (which includes
NUMA_NO_NODE), it may hide wrong values which would be previously
exposed.

Both differences will be rectified by the next patch.

To sum up, this patch makes no functional changes, except temporarily
hiding potentially buggy callers.  Restricting the checks in
alloc_pages_node() is left for the next patch which can in turn expose
more existing buggy callers.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Robin Holt <robinmholt@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Cliff Whickman <cpw@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08 15:35:28 -07:00
Kees Cook
61e57c0c3a cgroup: fix seq_show_option merge with legacy_name
When seq_show_option (commit a068acf2ee: "fs: create and use
seq_show_option for escaping") was merged, it did not correctly collide
with cgroup's addition of legacy_name (commit 3e1d2eed39: "cgroup:
introduce cgroup_subsys->legacy_name") changes.

This fixes the reported name.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08 15:35:28 -07:00
Linus Torvalds
12f03ee606 libnvdimm for 4.3:
1/ Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
    mechanism for adding device-driver-discovered memory regions to the
    kernel's direct map.  This facility is used by the pmem driver to
    enable pfn_to_page() operations on the page frames returned by DAX
    ('direct_access' in 'struct block_device_operations'). For now, the
    'memmap' allocation for these "device" pages comes from "System
    RAM".  Support for allocating the memmap from device memory will
    arrive in a later kernel.
 
 2/ Introduce memremap() to replace usages of ioremap_cache() and
    ioremap_wt().  memremap() drops the __iomem annotation for these
    mappings to memory that do not have i/o side effects.  The
    replacement of ioremap_cache() with memremap() is limited to the
    pmem driver to ease merging the api change in v4.3.  Completion of
    the conversion is targeted for v4.4.
 
 3/ Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
    driver, update the VFS DAX implementation and PMEM api to provide
    persistence guarantees for kernel operations on a DAX mapping.
 
 4/ Convert the ACPI NFIT 'BLK' driver to map the block apertures as
    cacheable to improve performance.
 
 5/ Miscellaneous updates and fixes to libnvdimm including support
    for issuing "address range scrub" commands, clarifying the optimal
    'sector size' of pmem devices, a clarification of the usage of the
    ACPI '_STA' (status) property for DIMM devices, and other minor
    fixes.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJV6Nx7AAoJEB7SkWpmfYgCWyYQAI5ju6Gvw27RNFtPovHcZUf5
 JGnxXejI6/AqeTQ+IulgprxtEUCrXOHjCDA5dkjr1qvsoqK1qxug+vJHOZLgeW0R
 OwDtmdW4Qrgeqm+CPoxETkorJ8wDOc8mol81kTiMgeV3UqbYeeHIiTAmwe7VzZ0C
 nNdCRDm5g8dHCjTKcvK3rvozgyoNoWeBiHkPe76EbnxDICxCB5dak7XsVKNMIVFQ
 NuYlnw6IYN7+rMHgpgpRux38NtIW8VlYPWTmHExejc2mlioWMNBG/bmtwLyJ6M3e
 zliz4/cnonTMUaizZaVozyinTa65m7wcnpjK+vlyGV2deDZPJpDRvSOtB0lH30bR
 1gy+qrKzuGKpaN6thOISxFLLjmEeYwzYd7SvC9n118r32qShz+opN9XX0WmWSFlA
 sajE1ehm4M7s5pkMoa/dRnAyR8RUPu4RNINdQ/Z9jFfAOx+Q26rLdQXwf9+uqbEb
 bIeSQwOteK5vYYCstvpAcHSMlJAglzIX5UfZBvtEIJN7rlb0VhmGWfxAnTu+ktG1
 o9cqAt+J4146xHaFwj5duTsyKhWb8BL9+xqbKPNpXEp+PbLsrnE/+WkDLFD67jxz
 dgIoK60mGnVXp+16I2uMqYYDgAyO5zUdmM4OygOMnZNa1mxesjbDJC6Wat1Wsndn
 slsw6DkrWT60CRE42nbK
 =o57/
 -----END PGP SIGNATURE-----

Merge tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "This update has successfully completed a 0day-kbuild run and has
  appeared in a linux-next release.  The changes outside of the typical
  drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the
  removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and
  the introduction of ZONE_DEVICE + devm_memremap_pages().

  Summary:

   - Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
     mechanism for adding device-driver-discovered memory regions to the
     kernel's direct map.

     This facility is used by the pmem driver to enable pfn_to_page()
     operations on the page frames returned by DAX ('direct_access' in
     'struct block_device_operations').

     For now, the 'memmap' allocation for these "device" pages comes
     from "System RAM".  Support for allocating the memmap from device
     memory will arrive in a later kernel.

   - Introduce memremap() to replace usages of ioremap_cache() and
     ioremap_wt().  memremap() drops the __iomem annotation for these
     mappings to memory that do not have i/o side effects.  The
     replacement of ioremap_cache() with memremap() is limited to the
     pmem driver to ease merging the api change in v4.3.

     Completion of the conversion is targeted for v4.4.

   - Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
     driver, update the VFS DAX implementation and PMEM api to provide
     persistence guarantees for kernel operations on a DAX mapping.

   - Convert the ACPI NFIT 'BLK' driver to map the block apertures as
     cacheable to improve performance.

   - Miscellaneous updates and fixes to libnvdimm including support for
     issuing "address range scrub" commands, clarifying the optimal
     'sector size' of pmem devices, a clarification of the usage of the
     ACPI '_STA' (status) property for DIMM devices, and other minor
     fixes"

* tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits)
  libnvdimm, pmem: direct map legacy pmem by default
  libnvdimm, pmem: 'struct page' for pmem
  libnvdimm, pfn: 'struct page' provider infrastructure
  x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB
  add devm_memremap_pages
  mm: ZONE_DEVICE for "device memory"
  mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h
  dax: drop size parameter to ->direct_access()
  nd_blk: change aperture mapping from WC to WB
  nvdimm: change to use generic kvfree()
  pmem, dax: have direct_access use __pmem annotation
  dax: update I/O path to do proper PMEM flushing
  pmem: add copy_from_iter_pmem() and clear_pmem()
  pmem, x86: clean up conditional pmem includes
  pmem: remove layer when calling arch_has_wmb_pmem()
  pmem, x86: move x86 PMEM API to new pmem.h header
  libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option
  pmem: switch to devm_ allocations
  devres: add devm_memremap
  libnvdimm, btt: write and validate parent_uuid
  ...
2015-09-08 14:35:59 -07:00
Linus Torvalds
59a47fff02 Mostly this is just clean ups and micro optimizations.
The changes with more meat are:
 
  o Allowing the trace event filters to filter on CPU number and process ids
 
  o Two new markers for trace output latency were added
     (10 and 100 msec latencies)
 
  o Have tracing_thresh filter function profiling time
 
 I also worked on modifying the ring buffer code for some future
 work, and moved the adding of the timestamp around. One of my changes
 caused a regression, and since other changes were built on top of it
 and already tested, I had to operate a revert of that change. Instead
 of rebasing, this change set has the code that caused a regression
 as well as the code to revert that change without touching the other
 changes that were made on top of it.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJV6aZEAAoJEEjnJuOKh9ldrR4H/A1RcQf1prLLoUibPP4w3lat
 dmQcdpS1NY+cqyiKuKPAOkFDGQL7qWzRqZ8whcPSJIsHq57ufqNSLf+0bbQYPzg9
 g3CgGL7OApmGi5ulj0sNxhadvc9TFm/SAN0nVJlNuUWdm8e1UWHLsrJZaMfopu2r
 RDEtkOhg619mhDL4rktNdS6rk0B92Fhu2o2PwLZPVlUl1NNEt4WJU+ejitXUVO1A
 Nb70/rTGGJKtyHbW+74on4LnEN5Uu0Viu6rMwGfYyIgRmC2otdBDvE4xfKMiTUKr
 SzBjzrhIoMIRn4Vl0vElfulkpYaw7pcC2BdpZ4d9VpIOiLSlZs0x/TgCtpFEv5M=
 =baZ3
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing update from Steven Rostedt:
 "Mostly this is just clean ups and micro optimizations.

  The changes with more meat are:

   - Allowing the trace event filters to filter on CPU number and
     process ids

   - Two new markers for trace output latency were added (10 and 100
     msec latencies)

   - Have tracing_thresh filter function profiling time

  I also worked on modifying the ring buffer code for some future work,
  and moved the adding of the timestamp around.  One of my changes
  caused a regression, and since other changes were built on top of it
  and already tested, I had to operate a revert of that change.  Instead
  of rebasing, this change set has the code that caused a regression as
  well as the code to revert that change without touching the other
  changes that were made on top of it"

* tag 'trace-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Revert "ring-buffer: Get timestamp after event is allocated"
  tracing: Don't make assumptions about length of string on task rename
  tracing: Allow triggers to filter for CPU ids and process names
  ftrace: Format MCOUNT_ADDR address as type unsigned long
  tracing: Introduce two additional marks for delay
  ftrace: Fix function_graph duration spacing with 7-digits
  ftrace: add tracing_thresh to function profile
  tracing: Clean up stack tracing and fix fentry updates
  ring-buffer: Reorganize function locations
  ring-buffer: Make sure event has enough room for extend and padding
  ring-buffer: Get timestamp after event is allocated
  ring-buffer: Move the adding of the extended timestamp out of line
  ring-buffer: Add event descriptor to simplify passing data
  ftrace: correct the counter increment for trace_buffer data
  tracing: Fix for non-continuous cpu ids
  tracing: Prefer kcalloc over kzalloc with multiply
2015-09-08 14:04:14 -07:00
Linus Torvalds
425afcff13 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit update from Paul Moore:
 "This is one of the larger audit patchsets in recent history,
  consisting of eight patches and almost 400 lines of changes.

  The bulk of the patchset is the new "audit by executable"
  functionality which allows admins to set an audit watch based on the
  executable on disk.  Prior to this, admins could only track an
  application by PID, which has some obvious limitations.

  Beyond the new functionality we also have some refcnt fixes and a few
  minor cleanups"

* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
  fixup: audit: implement audit by executable
  audit: implement audit by executable
  audit: clean simple fsnotify implementation
  audit: use macros for unset inode and device values
  audit: make audit_del_rule() more robust
  audit: fix uninitialized variable in audit_add_rule()
  audit: eliminate unnecessary extra layer of watch parent references
  audit: eliminate unnecessary extra layer of watch references
2015-09-08 13:34:59 -07:00
Linus Torvalds
b793c005ce Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Highlights:

   - PKCS#7 support added to support signed kexec, also utilized for
     module signing.  See comments in 3f1e1bea.

     ** NOTE: this requires linking against the OpenSSL library, which
        must be installed, e.g.  the openssl-devel on Fedora **

   - Smack
      - add IPv6 host labeling; ignore labels on kernel threads
      - support smack labeling mounts which use binary mount data

   - SELinux:
      - add ioctl whitelisting (see
        http://kernsec.org/files/lss2015/vanderstoep.pdf)
      - fix mprotect PROT_EXEC regression caused by mm change

   - Seccomp:
      - add ptrace options for suspend/resume"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (57 commits)
  PKCS#7: Add OIDs for sha224, sha284 and sha512 hash algos and use them
  Documentation/Changes: Now need OpenSSL devel packages for module signing
  scripts: add extract-cert and sign-file to .gitignore
  modsign: Handle signing key in source tree
  modsign: Use if_changed rule for extracting cert from module signing key
  Move certificate handling to its own directory
  sign-file: Fix warning about BIO_reset() return value
  PKCS#7: Add MODULE_LICENSE() to test module
  Smack - Fix build error with bringup unconfigured
  sign-file: Document dependency on OpenSSL devel libraries
  PKCS#7: Appropriately restrict authenticated attributes and content type
  KEYS: Add a name for PKEY_ID_PKCS7
  PKCS#7: Improve and export the X.509 ASN.1 time object decoder
  modsign: Use extract-cert to process CONFIG_SYSTEM_TRUSTED_KEYS
  extract-cert: Cope with multiple X.509 certificates in a single file
  sign-file: Generate CMS message as signature instead of PKCS#7
  PKCS#7: Support CMS messages also [RFC5652]
  X.509: Change recorded SKID & AKID to not include Subject or Issuer
  PKCS#7: Check content type and versions
  MAINTAINERS: The keyrings mailing list has moved
  ...
2015-09-08 12:41:25 -07:00
Linus Torvalds
7d9071a095 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "In this one:

   - d_move fixes (Eric Biederman)

   - UFS fixes (me; locking is mostly sane now, a bunch of bugs in error
     handling ought to be fixed)

   - switch of sb_writers to percpu rwsem (Oleg Nesterov)

   - superblock scalability (Josef Bacik and Dave Chinner)

   - swapon(2) race fix (Hugh Dickins)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits)
  vfs: Test for and handle paths that are unreachable from their mnt_root
  dcache: Reduce the scope of i_lock in d_splice_alias
  dcache: Handle escaped paths in prepend_path
  mm: fix potential data race in SyS_swapon
  inode: don't softlockup when evicting inodes
  inode: rename i_wb_list to i_io_list
  sync: serialise per-superblock sync operations
  inode: convert inode_sb_list_lock to per-sb
  inode: add hlist_fake to avoid the inode hash lock in evict
  writeback: plug writeback at a high level
  change sb_writers to use percpu_rw_semaphore
  shift percpu_counter_destroy() into destroy_super_work()
  percpu-rwsem: kill CONFIG_PERCPU_RWSEM
  percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire()
  percpu-rwsem: introduce percpu_down_read_trylock()
  document rwsem_release() in sb_wait_write()
  fix the broken lockdep logic in __sb_start_write()
  introduce __sb_writers_{acquired,release}() helpers
  ufs_inode_get{frag,block}(): get rid of 'phys' argument
  ufs_getfrag_block(): tidy up a bit
  ...
2015-09-05 20:34:28 -07:00
Linus Torvalds
6c0f568e84 Merge branch 'akpm' (patches from Andrew)
Merge patch-bomb from Andrew Morton:

 - a few misc things

 - Andy's "ambient capabilities"

 - fs/nofity updates

 - the ocfs2 queue

 - kernel/watchdog.c updates and feature work.

 - some of MM.  Includes Andrea's userfaultfd feature.

[ Hadn't noticed that userfaultfd was 'default y' when applying the
  patches, so that got fixed in this merge instead.  We do _not_ mark
  new features that nobody uses yet 'default y'   - Linus ]

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
  mm/hugetlb.c: make vma_has_reserves() return bool
  mm/madvise.c: make madvise_behaviour_valid() return bool
  mm/memory.c: make tlb_next_batch() return bool
  mm/dmapool.c: change is_page_busy() return from int to bool
  mm: remove struct node_active_region
  mremap: simplify the "overlap" check in mremap_to()
  mremap: don't do uneccesary checks if new_len == old_len
  mremap: don't do mm_populate(new_addr) on failure
  mm: move ->mremap() from file_operations to vm_operations_struct
  mremap: don't leak new_vma if f_op->mremap() fails
  mm/hugetlb.c: make vma_shareable() return bool
  mm: make GUP handle pfn mapping unless FOLL_GET is requested
  mm: fix status code which move_pages() returns for zero page
  mm: memcontrol: bring back the VM_BUG_ON() in mem_cgroup_swapout()
  genalloc: add support of multiple gen_pools per device
  genalloc: add name arg to gen_pool_get() and devm_gen_pool_create()
  mm/memblock: WARN_ON when nid differs from overlap region
  Documentation/features/vm: add feature description and arch support status for batched TLB flush after unmap
  mm: defer flush of writable TLB entries
  mm: send one IPI per CPU to TLB flush all entries after unmapping pages
  ...
2015-09-05 14:27:38 -07:00
Eric Dumazet
c821990610 task_work: remove fifo ordering guarantee
In commit f341861fb0 ("task_work: add a scheduling point in
task_work_run()") I fixed a latency problem adding a cond_resched()
call.

Later, commit ac3d0da8f3 added yet another loop to reverse a list,
bringing back the latency spike :

I've seen in some cases this loop taking 275 ms, if for example a
process with 2,000,000 files is killed.

We could add yet another cond_resched() in the reverse loop, or we
can simply remove the reversal, as I do not think anything
would depend on order of task_work_add() submitted works.

Fixes: ac3d0da8f3 ("task_work: Make task_work_add() lockless")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-05 13:46:58 -07:00
Andrea Arcangeli
1380fca084 userfaultfd: activate syscall
This activates the userfaultfd syscall.

[sfr@canb.auug.org.au: activate syscall fix]
[akpm@linux-foundation.org: don't enable userfaultfd on powerpc]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Cc: zhang.zhanghailiang@huawei.com
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Andrea Arcangeli
16ba6f811d userfaultfd: add VM_UFFD_MISSING and VM_UFFD_WP
These two flags gets set in vma->vm_flags to tell the VM common code
if the userfaultfd is armed and in which mode (only tracking missing
faults, only tracking wrprotect faults or both). If neither flags is
set it means the userfaultfd is not armed on the vma.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Cc: zhang.zhanghailiang@huawei.com
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Andrea Arcangeli
745f234be1 userfaultfd: add vm_userfaultfd_ctx to the vm_area_struct
This adds the vm_userfaultfd_ctx to the vm_area_struct.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Cc: zhang.zhanghailiang@huawei.com
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Andrea Arcangeli
51360155ec userfaultfd: waitqueue: add nr wake parameter to __wake_up_locked_key
userfaultfd needs to wake all waitqueues (pass 0 as nr parameter), instead
of the current hardcoded 1 (that would wake just the first waitqueue in
the head list).

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Cc: zhang.zhanghailiang@huawei.com
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Ulrich Obergfell
ec6a90661a watchdog: rename watchdog_suspend() and watchdog_resume()
Rename watchdog_suspend() to lockup_detector_suspend() and
watchdog_resume() to lockup_detector_resume() to avoid confusion with the
watchdog subsystem and to be consistent with the existing name
lockup_detector_init().

Also provide comment blocks to explain the watchdog_running and
watchdog_suspended variables and their relationship.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Stephane Eranian <eranian@google.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Ulrich Obergfell
999bbe49ea watchdog: use suspend/resume interface in fixup_ht_bug()
Remove watchdog_nmi_disable_all() and watchdog_nmi_enable_all() since
these functions are no longer needed.  If a subsystem has a need to
deactivate the watchdog temporarily, it should utilize the
watchdog_suspend() and watchdog_resume() functions.

[akpm@linux-foundation.org: fix build with CONFIG_LOCKUP_DETECTOR=m]
Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Stephane Eranian <eranian@google.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Ulrich Obergfell
d4bdd0b21c watchdog: use park/unpark functions in update_watchdog_all_cpus()
Remove update_watchdog() and restart_watchdog_hrtimer() since these
functions are no longer needed.  Changes of parameters such as the sample
period are honored at the time when the watchdog threads are being
unparked.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Stephane Eranian <eranian@google.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Ulrich Obergfell
8c073d27d7 watchdog: introduce watchdog_suspend() and watchdog_resume()
This interface can be utilized to deactivate the hard and soft lockup
detector temporarily.  Callers are expected to minimize the duration of
deactivation.  Multiple deactivations are allowed to occur in parallel but
should be rare in practice.

[akpm@linux-foundation.org: remove unneeded static initialization]
Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Stephane Eranian <eranian@google.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Ulrich Obergfell
81a4beef91 watchdog: introduce watchdog_park_threads() and watchdog_unpark_threads()
Originally watchdog_nmi_enable(cpu) and watchdog_nmi_disable(cpu) were
only called in watchdog thread context.  However, the following commits
utilize these functions outside of watchdog thread context too.

  commit 9809b18fcf
  Author: Michal Hocko <mhocko@suse.cz>
  Date:   Tue Sep 24 15:27:30 2013 -0700

      watchdog: update watchdog_thresh properly

  commit b3738d2932
  Author: Stephane Eranian <eranian@google.com>
  Date:   Mon Nov 17 20:07:03 2014 +0100

      watchdog: Add watchdog enable/disable all functions

Hence, it is now possible that these functions execute concurrently with
the same 'cpu' argument.  This concurrency is problematic because per-cpu
'watchdog_ev' can be accessed/modified without adequate synchronization.

The patch series aims to address the above problem.  However, instead of
introducing locks to protect per-cpu 'watchdog_ev' a different approach is
taken: Invoke these functions by parking and unparking the watchdog
threads (to ensure they are always called in watchdog thread context).

  static struct smp_hotplug_thread watchdog_threads = {
           ...
          .park   = watchdog_disable, // calls watchdog_nmi_disable()
          .unpark = watchdog_enable,  // calls watchdog_nmi_enable()
  };

Both previously mentioned commits call these functions in a similar way
and thus in principle contain some duplicate code.  The patch series also
avoids this duplication by providing a commonly usable mechanism.

- Patch 1/4 introduces the watchdog_{park|unpark}_threads functions that
  park/unpark all watchdog threads specified in 'watchdog_cpumask'. They
  are intended to be called inside of kernel/watchdog.c only.

- Patch 2/4 introduces the watchdog_{suspend|resume} functions which can
  be utilized by external callers to deactivate the hard and soft lockup
  detector temporarily.

- Patch 3/4 utilizes watchdog_{park|unpark}_threads to replace some code
  that was introduced by commit 9809b18fcf.

- Patch 4/4 utilizes watchdog_{suspend|resume} to replace some code that
  was introduced by commit b3738d2932.

A few corner cases should be mentioned here for completeness.

- kthread_park() of watchdog/N could hang if cpu N is already locked up.
  However, if watchdog is enabled the lockup will be detected anyway.

- kthread_unpark() of watchdog/N could hang if cpu N got locked up after
  kthread_park(). The occurrence of this scenario should be _very_ rare
  in practice, in particular because it is not expected that temporary
  deactivation will happen frequently, and if it happens at all it is
  expected that the duration of deactivation will be short.

This patch (of 4): introduce watchdog_park_threads() and watchdog_unpark_threads()

These functions are intended to be used only from inside kernel/watchdog.c
to park/unpark all watchdog threads that are specified in
watchdog_cpumask.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Stephane Eranian <eranian@google.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Guenter Roeck
aacfbe6a97 kernel/watchdog: move NMI function header declarations from watchdog.h to nmi.h
The kernel's NMI watchdog has nothing to do with the watchdog subsystem.
Its header declarations should be in linux/nmi.h, not linux/watchdog.h.

The code provided two sets of dummy functions if HARDLOCKUP_DETECTOR is
not configured, one in the include file and one in kernel/watchdog.c.
Remove the dummy functions from kernel/watchdog.c and use those from the
include file.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Stephane Eranian <eranian@google.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Frederic Weisbecker
314b08ff52 watchdog: simplify housekeeping affinity with the appropriate mask
housekeeping_mask gathers all the CPUs that aren't part of the nohz_full
set.  This is exactly what we want the watchdog to be affine to without
the need to use complicated cpumask operations.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Frederic Weisbecker
230ec93909 smpboot: allow passing the cpumask on per-cpu thread registration
It makes the registration cheaper and simpler for the smpboot per-cpu
kthread users that don't need to always update the cpumask after threads
creation.

[sfr@canb.auug.org.au: fix for allow passing the cpumask on per-cpu thread registration]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Chris Metcalf <cmetcalf@ezchip.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Frederic Weisbecker
3dd08c0c91 smpboot: make cleanup to mirror setup
The per-cpu kthread cleanup() callback is the mirror of the setup()
callback.  When the per-cpu kthread is started, it first calls setup()
to initialize the resources which are then released by cleanup() when
the kthread exits.

Now since the introduction of a per-cpu kthread cpumask, the kthreads
excluded by the cpumask on boot may happen to be parked immediately
after their creation without taking the setup() stage, waiting to be
asked to unpark to do so.  Then when smpboot_unregister_percpu_thread()
is later called, the kthread is stopped without having ever called
setup().

But this triggers a bug as the kthread unconditionally calls cleanup()
on exit but this doesn't mirror any setup().  Thus the kernel crashes
because we try to free resources that haven't been initialized, as in
the watchdog case:

    WATCHDOG disable 0
    WATCHDOG disable 1
    WATCHDOG disable 2
    BUG: unable to handle kernel NULL pointer dereference at           (null)
    IP: hrtimer_active+0x26/0x60
    [...]
    Call Trace:
      hrtimer_try_to_cancel+0x1c/0x280
      hrtimer_cancel+0x1d/0x30
      watchdog_disable+0x56/0x70
      watchdog_cleanup+0xe/0x10
      smpboot_thread_fn+0x23c/0x2c0
      kthread+0xf8/0x110
      ret_from_fork+0x3f/0x70

This bug is currently masked with explicit kthread unparking before
kthread_stop() on smpboot_destroy_threads(). This forces a call to
setup() and then unpark().

We could fix this by unconditionally calling setup() on kthread entry.
But setup() isn't always cheap.  In the case of watchdog it launches
hrtimer, perf events, etc...  So we may as well like to skip it if there
are chances the kthread will never be used, as in a reduced cpumask value.

So let's simply do a state machine check before calling cleanup() that
makes sure setup() has been called before mirroring it.

And remove the nasty hack workaround.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Chris Metcalf <cmetcalf@ezchip.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Frederic Weisbecker
5869b5064b smpboot: fix memory leak on error handling
The cpumask is allocated before threads get created. If the latter step
fails, we need to free the cpumask.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Chris Metcalf <cmetcalf@ezchip.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Kees Cook
a068acf2ee fs: create and use seq_show_option for escaping
Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g.  new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files.  This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else.  This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.

Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink).  Imagine the use
of "sudo" is something more sneaky:

  $ BASE="ovl"
  $ MNT="$BASE/mnt"
  $ LOW="$BASE/lower"
  $ UP="$BASE/upper"
  $ WORK="$BASE/work/ 0 0
  none /proc fuse.pwn user_id=1000"
  $ mkdir -p "$LOW" "$UP" "$WORK"
  $ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
  $ cat /proc/mounts
  none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
  none /proc fuse.pwn user_id=1000 0 0
  $ fusermount -u /proc
  $ cat /proc/mounts
  cat: /proc/mounts: No such file or directory

This fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed.  Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.

[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Jan Kara <jack@suse.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Cc: J. R. Okajima <hooanon05g@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Andy Lutomirski
58319057b7 capabilities: ambient capabilities
Credit where credit is due: this idea comes from Christoph Lameter with
a lot of valuable input from Serge Hallyn.  This patch is heavily based
on Christoph's patch.

===== The status quo =====

On Linux, there are a number of capabilities defined by the kernel.  To
perform various privileged tasks, processes can wield capabilities that
they hold.

Each task has four capability masks: effective (pE), permitted (pP),
inheritable (pI), and a bounding set (X).  When the kernel checks for a
capability, it checks pE.  The other capability masks serve to modify
what capabilities can be in pE.

Any task can remove capabilities from pE, pP, or pI at any time.  If a
task has a capability in pP, it can add that capability to pE and/or pI.
If a task has CAP_SETPCAP, then it can add any capability to pI, and it
can remove capabilities from X.

Tasks are not the only things that can have capabilities; files can also
have capabilities.  A file can have no capabilty information at all [1].
If a file has capability information, then it has a permitted mask (fP)
and an inheritable mask (fI) as well as a single effective bit (fE) [2].
File capabilities modify the capabilities of tasks that execve(2) them.

A task that successfully calls execve has its capabilities modified for
the file ultimately being excecuted (i.e.  the binary itself if that
binary is ELF or for the interpreter if the binary is a script.) [3] In
the capability evolution rules, for each mask Z, pZ represents the old
value and pZ' represents the new value.  The rules are:

  pP' = (X & fP) | (pI & fI)
  pI' = pI
  pE' = (fE ? pP' : 0)
  X is unchanged

For setuid binaries, fP, fI, and fE are modified by a moderately
complicated set of rules that emulate POSIX behavior.  Similarly, if
euid == 0 or ruid == 0, then fP, fI, and fE are modified differently
(primary, fP and fI usually end up being the full set).  For nonroot
users executing binaries with neither setuid nor file caps, fI and fP
are empty and fE is false.

As an extra complication, if you execute a process as nonroot and fE is
set, then the "secure exec" rules are in effect: AT_SECURE gets set,
LD_PRELOAD doesn't work, etc.

This is rather messy.  We've learned that making any changes is
dangerous, though: if a new kernel version allows an unprivileged
program to change its security state in a way that persists cross
execution of a setuid program or a program with file caps, this
persistent state is surprisingly likely to allow setuid or file-capped
programs to be exploited for privilege escalation.

===== The problem =====

Capability inheritance is basically useless.

If you aren't root and you execute an ordinary binary, fI is zero, so
your capabilities have no effect whatsoever on pP'.  This means that you
can't usefully execute a helper process or a shell command with elevated
capabilities if you aren't root.

On current kernels, you can sort of work around this by setting fI to
the full set for most or all non-setuid executable files.  This causes
pP' = pI for nonroot, and inheritance works.  No one does this because
it's a PITA and it isn't even supported on most filesystems.

If you try this, you'll discover that every nonroot program ends up with
secure exec rules, breaking many things.

This is a problem that has bitten many people who have tried to use
capabilities for anything useful.

===== The proposed change =====

This patch adds a fifth capability mask called the ambient mask (pA).
pA does what most people expect pI to do.

pA obeys the invariant that no bit can ever be set in pA if it is not
set in both pP and pI.  Dropping a bit from pP or pI drops that bit from
pA.  This ensures that existing programs that try to drop capabilities
still do so, with a complication.  Because capability inheritance is so
broken, setting KEEPCAPS, using setresuid to switch to nonroot uids, and
then calling execve effectively drops capabilities.  Therefore,
setresuid from root to nonroot conditionally clears pA unless
SECBIT_NO_SETUID_FIXUP is set.  Processes that don't like this can
re-add bits to pA afterwards.

The capability evolution rules are changed:

  pA' = (file caps or setuid or setgid ? 0 : pA)
  pP' = (X & fP) | (pI & fI) | pA'
  pI' = pI
  pE' = (fE ? pP' : pA')
  X is unchanged

If you are nonroot but you have a capability, you can add it to pA.  If
you do so, your children get that capability in pA, pP, and pE.  For
example, you can set pA = CAP_NET_BIND_SERVICE, and your children can
automatically bind low-numbered ports.  Hallelujah!

Unprivileged users can create user namespaces, map themselves to a
nonzero uid, and create both privileged (relative to their namespace)
and unprivileged process trees.  This is currently more or less
impossible.  Hallelujah!

You cannot use pA to try to subvert a setuid, setgid, or file-capped
program: if you execute any such program, pA gets cleared and the
resulting evolution rules are unchanged by this patch.

Users with nonzero pA are unlikely to unintentionally leak that
capability.  If they run programs that try to drop privileges, dropping
privileges will still work.

It's worth noting that the degree of paranoia in this patch could
possibly be reduced without causing serious problems.  Specifically, if
we allowed pA to persist across executing non-pA-aware setuid binaries
and across setresuid, then, naively, the only capabilities that could
leak as a result would be the capabilities in pA, and any attacker
*already* has those capabilities.  This would make me nervous, though --
setuid binaries that tried to privilege-separate might fail to do so,
and putting CAP_DAC_READ_SEARCH or CAP_DAC_OVERRIDE into pA could have
unexpected side effects.  (Whether these unexpected side effects would
be exploitable is an open question.) I've therefore taken the more
paranoid route.  We can revisit this later.

An alternative would be to require PR_SET_NO_NEW_PRIVS before setting
ambient capabilities.  I think that this would be annoying and would
make granting otherwise unprivileged users minor ambient capabilities
(CAP_NET_BIND_SERVICE or CAP_NET_RAW for example) much less useful than
it is with this patch.

===== Footnotes =====

[1] Files that are missing the "security.capability" xattr or that have
unrecognized values for that xattr end up with has_cap set to false.
The code that does that appears to be complicated for no good reason.

[2] The libcap capability mask parsers and formatters are dangerously
misleading and the documentation is flat-out wrong.  fE is *not* a mask;
it's a single bit.  This has probably confused every single person who
has tried to use file capabilities.

[3] Linux very confusingly processes both the script and the interpreter
if applicable, for reasons that elude me.  The results from thinking
about a script's file capabilities and/or setuid bits are mostly
discarded.

Preliminary userspace code is here, but it needs updating:
https://git.kernel.org/cgit/linux/kernel/git/luto/util-linux-playground.git/commit/?h=cap_ambient&id=7f5afbd175d2

Here is a test program that can be used to verify the functionality
(from Christoph):

/*
 * Test program for the ambient capabilities. This program spawns a shell
 * that allows running processes with a defined set of capabilities.
 *
 * (C) 2015 Christoph Lameter <cl@linux.com>
 * Released under: GPL v3 or later.
 *
 *
 * Compile using:
 *
 *	gcc -o ambient_test ambient_test.o -lcap-ng
 *
 * This program must have the following capabilities to run properly:
 * Permissions for CAP_NET_RAW, CAP_NET_ADMIN, CAP_SYS_NICE
 *
 * A command to equip the binary with the right caps is:
 *
 *	setcap cap_net_raw,cap_net_admin,cap_sys_nice+p ambient_test
 *
 *
 * To get a shell with additional caps that can be inherited by other processes:
 *
 *	./ambient_test /bin/bash
 *
 *
 * Verifying that it works:
 *
 * From the bash spawed by ambient_test run
 *
 *	cat /proc/$$/status
 *
 * and have a look at the capabilities.
 */

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <cap-ng.h>
#include <sys/prctl.h>
#include <linux/capability.h>

/*
 * Definitions from the kernel header files. These are going to be removed
 * when the /usr/include files have these defined.
 */
#define PR_CAP_AMBIENT 47
#define PR_CAP_AMBIENT_IS_SET 1
#define PR_CAP_AMBIENT_RAISE 2
#define PR_CAP_AMBIENT_LOWER 3
#define PR_CAP_AMBIENT_CLEAR_ALL 4

static void set_ambient_cap(int cap)
{
	int rc;

	capng_get_caps_process();
	rc = capng_update(CAPNG_ADD, CAPNG_INHERITABLE, cap);
	if (rc) {
		printf("Cannot add inheritable cap\n");
		exit(2);
	}
	capng_apply(CAPNG_SELECT_CAPS);

	/* Note the two 0s at the end. Kernel checks for these */
	if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, cap, 0, 0)) {
		perror("Cannot set cap");
		exit(1);
	}
}

int main(int argc, char **argv)
{
	int rc;

	set_ambient_cap(CAP_NET_RAW);
	set_ambient_cap(CAP_NET_ADMIN);
	set_ambient_cap(CAP_SYS_NICE);

	printf("Ambient_test forking shell\n");
	if (execv(argv[1], argv + 1))
		perror("Cannot exec");

	return 0;
}

Signed-off-by: Christoph Lameter <cl@linux.com> # Original author
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Aaron Jones <aaronmdjones@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Andrew G. Morgan <morgan@kernel.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Austin S Hemmelgarn <ahferroin7@gmail.com>
Cc: Markku Savela <msa@moth.iki.fi>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: James Morris <james.l.morris@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Andrew Morton
e9f069868d kernel/kthread.c:kthread_create_on_node(): clarify documentation
- Make it clear that the `node' arg refers to memory allocations only:
  kthread_create_on_node() does not pin the new thread to that node's
  CPUs.

- Encourage the use of NUMA_NO_NODE.

[nzimmer@sgi.com: use NUMA_NO_NODE in kthread_create() also]
Cc: Nathan Zimmer <nzimmer@sgi.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Linus Torvalds
ca520cab25 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking and atomic updates from Ingo Molnar:
 "Main changes in this cycle are:

   - Extend atomic primitives with coherent logic op primitives
     (atomic_{or,and,xor}()) and deprecate the old partial APIs
     (atomic_{set,clear}_mask())

     The old ops were incoherent with incompatible signatures across
     architectures and with incomplete support.  Now every architecture
     supports the primitives consistently (by Peter Zijlstra)

   - Generic support for 'relaxed atomics':

       - _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return()
       - atomic_read_acquire()
       - atomic_set_release()

     This came out of porting qwrlock code to arm64 (by Will Deacon)

   - Clean up the fragile static_key APIs that were causing repeat bugs,
     by introducing a new one:

       DEFINE_STATIC_KEY_TRUE(name);
       DEFINE_STATIC_KEY_FALSE(name);

     which define a key of different types with an initial true/false
     value.

     Then allow:

       static_branch_likely()
       static_branch_unlikely()

     to take a key of either type and emit the right instruction for the
     case.  To be able to know the 'type' of the static key we encode it
     in the jump entry (by Peter Zijlstra)

   - Static key self-tests (by Jason Baron)

   - qrwlock optimizations (by Waiman Long)

   - small futex enhancements (by Davidlohr Bueso)

   - ... and misc other changes"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits)
  jump_label/x86: Work around asm build bug on older/backported GCCs
  locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations
  locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h
  locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
  locking/qrwlock: Implement queue_write_unlock() using smp_store_release()
  locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
  locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t'
  locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication
  locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
  locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic
  locking/static_keys: Make verify_keys() static
  jump label, locking/static_keys: Update docs
  locking/static_keys: Provide a selftest
  jump_label: Provide a self-test
  s390/uaccess, locking/static_keys: employ static_branch_likely()
  x86, tsc, locking/static_keys: Employ static_branch_likely()
  locking/static_keys: Add selftest
  locking/static_keys: Add a new static_key interface
  locking/static_keys: Rework update logic
  locking/static_keys: Add static_key_{en,dis}able() helpers
  ...
2015-09-03 15:46:07 -07:00
Linus Torvalds
dd5cdb48ed Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Another merge window, another set of networking changes.  I've heard
  rumblings that the lightweight tunnels infrastructure has been voted
  networking change of the year.  But what do I know?

   1) Add conntrack support to openvswitch, from Joe Stringer.

   2) Initial support for VRF (Virtual Routing and Forwarding), which
      allows the segmentation of routing paths without using multiple
      devices.  There are some semantic kinks to work out still, but
      this is a reasonably strong foundation.  From David Ahern.

   3) Remove spinlock fro act_bpf fast path, from Alexei Starovoitov.

   4) Ignore route nexthops with a link down state in ipv6, just like
      ipv4.  From Andy Gospodarek.

   5) Remove spinlock from fast path of act_gact and act_mirred, from
      Eric Dumazet.

   6) Document the DSA layer, from Florian Fainelli.

   7) Add netconsole support to bcmgenet, systemport, and DSA.  Also
      from Florian Fainelli.

   8) Add Mellanox Switch Driver and core infrastructure, from Jiri
      Pirko.

   9) Add support for "light weight tunnels", which allow for
      encapsulation and decapsulation without bearing the overhead of a
      full blown netdevice.  From Thomas Graf, Jiri Benc, and a cast of
      others.

  10) Add Identifier Locator Addressing support for ipv6, from Tom
      Herbert.

  11) Support fragmented SKBs in iwlwifi, from Johannes Berg.

  12) Allow perf PMUs to be accessed from eBPF programs, from Kaixu Xia.

  13) Add BQL support to 3c59x driver, from Loganaden Velvindron.

  14) Stop using a zero TX queue length to mean that a device shouldn't
      have a qdisc attached, use an explicit flag instead.  From Phil
      Sutter.

  15) Use generic geneve netdevice infrastructure in openvswitch, from
      Pravin B Shelar.

  16) Add infrastructure to avoid re-forwarding a packet in software
      that was already forwarded by a hardware switch.  From Scott
      Feldman.

  17) Allow AF_PACKET fanout function to be implemented in a bpf
      program, from Willem de Bruijn"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1458 commits)
  netfilter: nf_conntrack: make nf_ct_zone_dflt built-in
  netfilter: nf_dup{4, 6}: fix build error when nf_conntrack disabled
  net: fec: clear receive interrupts before processing a packet
  ipv6: fix exthdrs offload registration in out_rt path
  xen-netback: add support for multicast control
  bgmac: Update fixed_phy_register()
  sock, diag: fix panic in sock_diag_put_filterinfo
  flow_dissector: Use 'const' where possible.
  flow_dissector: Fix function argument ordering dependency
  ixgbe: Resolve "initialized field overwritten" warnings
  ixgbe: Remove bimodal SR-IOV disabling
  ixgbe: Add support for reporting 2.5G link speed
  ixgbe: fix bounds checking in ixgbe_setup_tc for 82598
  ixgbe: support for ethtool set_rxfh
  ixgbe: Avoid needless PHY access on copper phys
  ixgbe: cleanup to use cached mask value
  ixgbe: Remove second instance of lan_id variable
  ixgbe: use kzalloc for allocating one thing
  flow: Move __get_hash_from_flowi{4,6} into flow_dissector.c
  ixgbe: Remove unused PCI bus types
  ...
2015-09-03 08:08:17 -07:00
Steven Rostedt (Red Hat)
b7dc42fd79 ring-buffer: Revert "ring-buffer: Get timestamp after event is allocated"
The commit a4543a2fa9 "ring-buffer: Get timestamp after event is
allocated" is needed for some future work. But after adding it, there is a
race somewhere that causes the saved timestamp to have a slight shift, and
get ahead of the actual timestamp and make it look like time goes backwards.

I'm still looking into why this happens, but in the mean time, this is
holding up other work to get in. I'm reverting the change for now (which
makes the problem go away), and will add it back after I know what is wrong
and fix it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-09-03 08:57:12 -04:00
Lina Iyer
21dd33b09c kernel/cpu_pm: fix cpu_cluster_pm_exit comment
cpu_cluster_pm_exit() must be sent after cpu_cluster_pm_enter() has been
sent for the cluster and before any cpu_pm_exit() notifications are sent
for any CPU.

Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-03 02:42:20 +02:00
Linus Torvalds
1081230b74 Merge branch 'for-4.3/core' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
 "This first core part of the block IO changes contains:

   - Cleanup of the bio IO error signaling from Christoph.  We used to
     rely on the uptodate bit and passing around of an error, now we
     store the error in the bio itself.

   - Improvement of the above from myself, by shrinking the bio size
     down again to fit in two cachelines on x86-64.

   - Revert of the max_hw_sectors cap removal from a revision again,
     from Jeff Moyer.  This caused performance regressions in various
     tests.  Reinstate the limit, bump it to a more reasonable size
     instead.

   - Make /sys/block/<dev>/queue/discard_max_bytes writeable, by me.
     Most devices have huge trim limits, which can cause nasty latencies
     when deleting files.  Enable the admin to configure the size down.
     We will look into having a more sane default instead of UINT_MAX
     sectors.

   - Improvement of the SGP gaps logic from Keith Busch.

   - Enable the block core to handle arbitrarily sized bios, which
     enables a nice simplification of bio_add_page() (which is an IO hot
     path).  From Kent.

   - Improvements to the partition io stats accounting, making it
     faster.  From Ming Lei.

   - Also from Ming Lei, a basic fixup for overflow of the sysfs pending
     file in blk-mq, as well as a fix for a blk-mq timeout race
     condition.

   - Ming Lin has been carrying Kents above mentioned patches forward
     for a while, and testing them.  Ming also did a few fixes around
     that.

   - Sasha Levin found and fixed a use-after-free problem introduced by
     the bio->bi_error changes from Christoph.

   - Small blk cgroup cleanup from Viresh Kumar"

* 'for-4.3/core' of git://git.kernel.dk/linux-block: (26 commits)
  blk: Fix bio_io_vec index when checking bvec gaps
  block: Replace SG_GAPS with new queue limits mask
  block: bump BLK_DEF_MAX_SECTORS to 2560
  Revert "block: remove artifical max_hw_sectors cap"
  blk-mq: fix race between timeout and freeing request
  blk-mq: fix buffer overflow when reading sysfs file of 'pending'
  Documentation: update notes in biovecs about arbitrarily sized bios
  block: remove bio_get_nr_vecs()
  fs: use helper bio_add_page() instead of open coding on bi_io_vec
  block: kill merge_bvec_fn() completely
  md/raid5: get rid of bio_fits_rdev()
  md/raid5: split bio for chunk_aligned_read
  block: remove split code in blkdev_issue_{discard,write_same}
  btrfs: remove bio splitting and merge_bvec_fn() calls
  bcache: remove driver private bio splitting code
  block: simplify bio_add_page()
  block: make generic_make_request handle arbitrarily sized bios
  blk-cgroup: Drop unlikely before IS_ERR(_OR_NULL)
  block: don't access bio->bi_error after bio_put()
  block: shrink struct bio down to 2 cache lines again
  ...
2015-09-02 13:10:25 -07:00
Linus Torvalds
8bdc69b764 Merge branch 'for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:

 - a new PIDs controller is added.  It turns out that PIDs are actually
   an independent resource from kmem due to the limited PID space.

 - more core preparations for the v2 interface.  Once cpu side interface
   is settled, it should be ready for lifting the devel mask.
   for-4.3-unified-base was temporarily branched so that other trees
   (block) can pull cgroup core changes that blkcg changes depend on.

 - a non-critical idr_preload usage bug fix.

* 'for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: pids: fix invalid get/put usage
  cgroup: introduce cgroup_subsys->legacy_name
  cgroup: don't print subsystems for the default hierarchy
  cgroup: make cftype->private a unsigned long
  cgroup: export cgrp_dfl_root
  cgroup: define controller file conventions
  cgroup: fix idr_preload usage
  cgroup: add documentation for the PIDs controller
  cgroup: implement the PIDs subsystem
  cgroup: allow a cgroup subsystem to reject a fork
2015-09-02 08:04:23 -07:00
Linus Torvalds
7d3e2eb178 Merge branch 'for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue updates from Tejun Heo:
 "Only three trivial changes for workqueue this time - doc, MAINTAINERS
  and EXPORT_SYMBOL updates"

* 'for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix some docbook warnings
  workqueue: Make flush_workqueue() available again to non GPL modules
  workqueue: add myself as a dedicated reviwer
2015-09-02 08:02:20 -07:00
Frederic Weisbecker
7c8bb6cb95 nohz: Assert existing housekeepers when nohz full enabled
The code ensures that when nohz full is running, at least the
boot CPU serves as a housekeeper and it can't be later offlined.

Let's assert this assumption to make sure that we have CPUs to
handle unbound jobs like workqueues and timers while nohz full
CPUs run undisturbed.

Also improve the comments on housekeeper offlining prevention.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Vatika Harlalka <vatikaharlalka@gmail.com>
Link: http://lkml.kernel.org/r/1441119060-2230-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-02 10:33:22 +02:00
Vatika Harlalka
9642d18eee nohz: Affine unpinned timers to housekeepers
The problem addressed in this patch is about affining unpinned
timers. Adaptive or Full Dynticks CPUs are currently disturbed
by unnecessary jitter due to firing of such timers on them.

This patch will affine timers to online CPUs which are not full
dynticks in NOHZ_FULL configured systems. It should not
introduce overhead in nohz full off case due to static keys.

Signed-off-by: Vatika Harlalka <vatikaharlalka@gmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1441119060-2230-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-02 10:33:22 +02:00
Linus Torvalds
ae98207309 Power management and ACPI material for v4.3-rc1
- ACPICA update to upstream revision 20150818 including method
    tracing extensions to allow more in-depth AML debugging in the
    kernel and a number of assorted fixes and cleanups (Bob Moore,
    Lv Zheng, Markus Elfring).
 
  - ACPI sysfs code updates and a documentation update related to
    AML method tracing (Lv Zheng).
 
  - ACPI EC driver fix related to serialized evaluations of _Qxx
    methods and ACPI tools updates allowing the EC userspace tool
    to be built from the kernel source (Lv Zheng).
 
  - ACPI processor driver updates preparing it for future
    introduction of CPPC support and ACPI PCC mailbox driver
    updates (Ashwin Chaugule).
 
  - ACPI interrupts enumeration fix for a regression related
    to the handling of IRQ attribute conflicts between MADT
    and the ACPI namespace (Jiang Liu).
 
  - Fixes related to ACPI device PM (Mika Westerberg, Srinidhi Kasagar).
 
  - ACPI device registration code reorganization to separate the
    sysfs-related code and bus type operations from the rest (Rafael
    J Wysocki).
 
  - Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause,
    Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss).
 
  - ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups
    (Pan Xinhui, Rafael J Wysocki).
 
  - cpufreq core cleanups on top of the previous changes allowing it
    to preseve its sysfs directories over system suspend/resume (Viresh
    Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior).
 
  - cpufreq fixes and cleanups related to governors (Viresh Kumar).
 
  - cpufreq updates (core and the cpufreq-dt driver) related to the
    turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz).
 
  - New DT bindings for Operating Performance Points (OPP), support
    for them in the OPP framework and in the cpufreq-dt driver plus
    related OPP framework fixes and cleanups (Viresh Kumar).
 
  - cpufreq powernv driver updates (Shilpasri G Bhat).
 
  - New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen).
 
  - Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups
    and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean).
 
  - intel_pstate driver updates including Skylake-S support, support
    for enabling HW P-states per CPU and an additional vendor bypass
    list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao).
 
  - cpuidle core fixes related to the handling of coupled idle states
    (Xunlei Pang).
 
  - intel_idle driver updates including Skylake Client support and
    support for freeze-mode-specific idle states (Len Brown).
 
  - Driver core updates related to power management (Andy Shevchenko,
    Rafael J Wysocki).
 
  - Generic power domains framework fixes and cleanups (Jon Hunter,
    Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson).
 
  - Device PM QoS framework update to allow the latency tolerance
    setting to be exposed to user space via sysfs (Mika Westerberg).
 
  - devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect
    exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas).
 
  - System sleep support updates (Alan Stern, Len Brown, SungEun Kim).
 
  - rockchip-io AVS support updates (Heiko Stuebner).
 
  - PM core clocks support fixup (Colin Ian King).
 
  - Power capping RAPL driver update including support for Skylake H/S
    and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi).
 
  - Generic device properties framework fixes related to the handling
    of static (driver-provided) property sets (Andy Shevchenko).
 
  - turbostat and cpupower updates (Len Brown, Shilpasri G Bhat,
    Shreyas B Prabhu).
 
 /
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQIcBAABCAAGBQJV5hhGAAoJEILEb/54YlRxs+EQAK51iFk48+IbpHYaZZ50Yo4m
 ZZc2zBcbwRcBlU9vKERrhG+jieSl8J/JJNxT8vBjKqyvNw038mCjewQh02ol0HuC
 R7nlDiVJkmZ50sLO4xwE/1UBZr/XqbddwCUnYzvFMkMTA0ePzFtf8BrJ1FXpT8S/
 fkwSXQty6hvJDwxkfrbMSaA730wMju9lahx8D6MlmUAedWYZOJDMQKB4WKa/St5X
 9uckBPHUBB2KiKlXxdbFPwKLNxHvLROq5SpDLc6cM/7XZB+QfNFy85CUjCUtYo1O
 1W8k0qnztvZ6UEv27qz5dejGyAGOarMWGGNsmL9evoeGeHRpQL+dom7HcTnbAfUZ
 walyhYSm/zKkdy7Vl3xWUUQkMG48+PviMI6K0YhHXb3Rm5wlR/yBNZTwNIty9SX/
 fKCHEa8QynWwLxgm53c3xRkiitJxMsHNK03moLD9zQMjshTyTNvpNbZoahyKQzk6
 H+9M1DBRHhkkREDWSwGutukxfEMtWe2vcZcyERrFiY7l5k1j58DwDBMPqjPhRv6q
 P/1NlCzr0XYf83Y86J18LbDuPGDhTjjIEn6CqbtI2mmWqTg3+rF7zvS2ux+FzMnA
 gisv8l6GT9JiWhxKFqqL/rrVpwtyHebWLYE/RpNUW6fEzLziRNj1qyYO9dqI/GGi
 I3rfxlXoc/5xJWCgNB8f
 =fTgI
 -----END PGP SIGNATURE-----

Merge tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "From the number of commits perspective, the biggest items are ACPICA
  and cpufreq changes with the latter taking the lead (over 50 commits).

  On the cpufreq front, there are many cleanups and minor fixes in the
  core and governors, driver updates etc.  We also have a new cpufreq
  driver for Mediatek MT8173 chips.

  ACPICA mostly updates its debug infrastructure and adds a number of
  fixes and cleanups for a good measure.

  The Operating Performance Points (OPP) framework is updated with new
  DT bindings and support for them among other things.

  We have a few updates of the generic power domains framework and a
  reorganization of the ACPI device enumeration code and bus type
  operations.

  And a lot of fixes and cleanups all over.

  Included is one branch from the MFD tree as it contains some
  PM-related driver core and ACPI PM changes a few other commits are
  based on.

  Specifics:

   - ACPICA update to upstream revision 20150818 including method
     tracing extensions to allow more in-depth AML debugging in the
     kernel and a number of assorted fixes and cleanups (Bob Moore, Lv
     Zheng, Markus Elfring).

   - ACPI sysfs code updates and a documentation update related to AML
     method tracing (Lv Zheng).

   - ACPI EC driver fix related to serialized evaluations of _Qxx
     methods and ACPI tools updates allowing the EC userspace tool to be
     built from the kernel source (Lv Zheng).

   - ACPI processor driver updates preparing it for future introduction
     of CPPC support and ACPI PCC mailbox driver updates (Ashwin
     Chaugule).

   - ACPI interrupts enumeration fix for a regression related to the
     handling of IRQ attribute conflicts between MADT and the ACPI
     namespace (Jiang Liu).

   - Fixes related to ACPI device PM (Mika Westerberg, Srinidhi
     Kasagar).

   - ACPI device registration code reorganization to separate the
     sysfs-related code and bus type operations from the rest (Rafael J
     Wysocki).

   - Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause,
     Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss).

   - ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups (Pan
     Xinhui, Rafael J Wysocki).

   - cpufreq core cleanups on top of the previous changes allowing it to
     preseve its sysfs directories over system suspend/resume (Viresh
     Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior).

   - cpufreq fixes and cleanups related to governors (Viresh Kumar).

   - cpufreq updates (core and the cpufreq-dt driver) related to the
     turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz).

   - New DT bindings for Operating Performance Points (OPP), support for
     them in the OPP framework and in the cpufreq-dt driver plus related
     OPP framework fixes and cleanups (Viresh Kumar).

   - cpufreq powernv driver updates (Shilpasri G Bhat).

   - New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen).

   - Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups
     and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean).

   - intel_pstate driver updates including Skylake-S support, support
     for enabling HW P-states per CPU and an additional vendor bypass
     list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao).

   - cpuidle core fixes related to the handling of coupled idle states
     (Xunlei Pang).

   - intel_idle driver updates including Skylake Client support and
     support for freeze-mode-specific idle states (Len Brown).

   - Driver core updates related to power management (Andy Shevchenko,
     Rafael J Wysocki).

   - Generic power domains framework fixes and cleanups (Jon Hunter,
     Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson).

   - Device PM QoS framework update to allow the latency tolerance
     setting to be exposed to user space via sysfs (Mika Westerberg).

   - devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect
     exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas).

   - System sleep support updates (Alan Stern, Len Brown, SungEun Kim).

   - rockchip-io AVS support updates (Heiko Stuebner).

   - PM core clocks support fixup (Colin Ian King).

   - Power capping RAPL driver update including support for Skylake H/S
     and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi).

   - Generic device properties framework fixes related to the handling
     of static (driver-provided) property sets (Andy Shevchenko).

   - turbostat and cpupower updates (Len Brown, Shilpasri G Bhat,
     Shreyas B Prabhu)"

* tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (180 commits)
  cpufreq: speedstep-lib: Use monotonic clock
  cpufreq: powernv: Increase the verbosity of OCC console messages
  cpufreq: sfi: use kmemdup rather than duplicating its implementation
  cpufreq: drop !cpufreq_driver check from cpufreq_parse_governor()
  cpufreq: rename cpufreq_real_policy as cpufreq_user_policy
  cpufreq: remove redundant 'policy' field from user_policy
  cpufreq: remove redundant 'governor' field from user_policy
  cpufreq: update user_policy.* on success
  cpufreq: use memcpy() to copy policy
  cpufreq: remove redundant CPUFREQ_INCOMPATIBLE notifier event
  cpufreq: mediatek: Add MT8173 cpufreq driver
  dt-bindings: mediatek: Add MT8173 CPU DVFS clock bindings
  PM / Domains: Fix typo in description of genpd_dev_pm_detach()
  PM / Domains: Remove unusable governor dummies
  PM / Domains: Make pm_genpd_init() available to modules
  PM / domains: Align column headers and data in pm_genpd_summary output
  powercap / RAPL: disable the 2nd power limit properly
  tools: cpupower: Fix error when running cpupower monitor
  PM / OPP: Drop unlikely before IS_ERR(_OR_NULL)
  PM / OPP: Fix static checker warning (broken 64bit big endian systems)
  ...
2015-09-01 19:45:46 -07:00
Linus Torvalds
089b669506 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "The usual stuff from trivial tree for 4.3 (kerneldoc updates, printk()
  fixes, Documentation and MAINTAINERS updates)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
  MAINTAINERS: update my e-mail address
  mod_devicetable: add space before */
  scsi: a100u2w: trivial typo in printk
  i2c: Fix typo in i2c-bfin-twi.c
  treewide: fix typos in comment blocks
  Doc: fix trivial typo in SubmittingPatches
  proportions: Spelling s/consitent/consistent/
  dm: Spelling s/consitent/consistent/
  aic7xxx: Fix typo in error message
  pcmcia: Fix typo in locking documentation
  scsi/arcmsr: Fix typos in error log
  drm/nouveau/gr: Fix typo in nv10.c
  [SCSI] Fix printk typos in drivers/scsi
  staging: comedi: Grammar s/Enable support a/Enable support for a/
  Btrfs: Spelling s/consitent/consistent/
  README: GTK+ is a acronym
  ASoC: omap: Fix typo in config option description
  mm: tlb.c: Fix error message
  ntfs: super.c: Fix error log
  fix typo in Documentation/SubmittingPatches
  ...
2015-09-01 18:46:42 -07:00
Linus Torvalds
45c680b994 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatching fix from Jiri Kosina:
 "Livepatching error handling fix"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: Improve error handling in klp_disable_func()
2015-09-01 18:44:28 -07:00
Linus Torvalds
73b6fa8e49 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace updates from Eric Biederman:
 "This finishes up the changes to ensure proc and sysfs do not start
  implementing executable files, as the there are application today that
  are only secure because such files do not exist.

  It akso fixes a long standing misfeature of /proc/<pid>/mountinfo that
  did not show the proper source for files bind mounted from
  /proc/<pid>/ns/*.

  It also straightens out the handling of clone flags related to user
  namespaces, fixing an unnecessary failure of unshare(CLONE_NEWUSER)
  when files such as /proc/<pid>/environ are read while <pid> is calling
  unshare.  This winds up fixing a minor bug in unshare flag handling
  that dates back to the first version of unshare in the kernel.

  Finally, this fixes a minor regression caused by the introduction of
  sysfs_create_mount_point, which broke someone's in house application,
  by restoring the size of /sys/fs/cgroup to 0 bytes.  Apparently that
  application uses the directory size to determine if a tmpfs is mounted
  on /sys/fs/cgroup.

  The bind mount escape fixes are present in Al Viros for-next branch.
  and I expect them to come from there.  The bind mount escape is the
  last of the user namespace related security bugs that I am aware of"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  fs: Set the size of empty dirs to 0.
  userns,pidns: Force thread group sharing, not signal handler sharing.
  unshare: Unsharing a thread does not require unsharing a vm
  nsfs: Add a show_path method to fix mountinfo
  mnt: fs_fully_visible enforce noexec and nosuid  if !SB_I_NOEXEC
  vfs: Commit to never having exectuables on proc and sysfs.
2015-09-01 16:13:25 -07:00
Linus Torvalds
17e6b00ac4 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "This updated pull request does not contain the last few GIC related
  patches which were reported to cause a regression.  There is a fix
  available, but I let it breed for a couple of days first.

  The irq departement provides:

   - new infrastructure to support non PCI based MSI interrupts
   - a couple of new irq chip drivers
   - the usual pile of fixlets and updates to irq chip drivers
   - preparatory changes for removal of the irq argument from interrupt
     flow handlers
   - preparatory changes to remove IRQF_VALID"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
  irqchip/imx-gpcv2: IMX GPCv2 driver for wakeup sources
  irqchip: Add bcm2836 interrupt controller for Raspberry Pi 2
  irqchip: Add documentation for the bcm2836 interrupt controller
  irqchip/bcm2835: Add support for being used as a second level controller
  irqchip/bcm2835: Refactor handle_IRQ() calls out of MAKE_HWIRQ
  PCI: xilinx: Fix typo in function name
  irqchip/gic: Ensure gic_cpu_if_up/down() programs correct GIC instance
  irqchip/gic: Only allow the primary GIC to set the CPU map
  PCI/MSI: pci-xgene-msi: Consolidate chained IRQ handler install/remove
  unicore32/irq: Prepare puv3_gpio_handler for irq argument removal
  tile/pci_gx: Prepare trio_handle_level_irq for irq argument removal
  m68k/irq: Prepare irq handlers for irq argument removal
  C6X/megamode-pic: Prepare megamod_irq_cascade for irq argument removal
  blackfin: Prepare irq handlers for irq argument removal
  arc/irq: Prepare idu_cascade_isr for irq argument removal
  sparc/irq: Use access helper irq_data_get_affinity_mask()
  sparc/irq: Use helper irq_data_get_irq_handler_data()
  parisc/irq: Use access helper irq_data_get_affinity_mask()
  mn10300/irq: Use access helper irq_data_get_affinity_mask()
  irqchip/i8259: Prepare i8259_irq_dispatch for irq argument removal
  ...
2015-09-01 14:33:35 -07:00
Linus Torvalds
5e359bf221 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "Rather large, but nothing exiting:

   - new range check for settimeofday() to prevent that boot time
     becomes negative.
   - fix for file time rounding
   - a few simplifications of the hrtimer code
   - fix for the proc/timerlist code so the output of clock realtime
     timers is accurate
   - more y2038 work
   - tree wide conversion of clockevent drivers to the new callbacks"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (88 commits)
  hrtimer: Handle failure of tick_init_highres() gracefully
  hrtimer: Unconfuse switch_hrtimer_base() a bit
  hrtimer: Simplify get_target_base() by returning current base
  hrtimer: Drop return code of hrtimer_switch_to_hres()
  time: Introduce timespec64_to_jiffies()/jiffies_to_timespec64()
  time: Introduce current_kernel_time64()
  time: Introduce struct itimerspec64
  time: Add the common weak version of update_persistent_clock()
  time: Always make sure wall_to_monotonic isn't positive
  time: Fix nanosecond file time rounding in timespec_trunc()
  timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers
  cris/time: Migrate to new 'set-state' interface
  kernel: broadcast-hrtimer: Migrate to new 'set-state' interface
  xtensa/time: Migrate to new 'set-state' interface
  unicore/time: Migrate to new 'set-state' interface
  um/time: Migrate to new 'set-state' interface
  sparc/time: Migrate to new 'set-state' interface
  sh/localtimer: Migrate to new 'set-state' interface
  score/time: Migrate to new 'set-state' interface
  s390/time: Migrate to new 'set-state' interface
  ...
2015-09-01 14:04:50 -07:00
Linus Torvalds
5778077d03 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm changes from Ingo Molnar:
 "The biggest changes in this cycle were:

   - Revamp, simplify (and in some cases fix) Time Stamp Counter (TSC)
     primitives.  (Andy Lutomirski)

   - Add new, comprehensible entry and exit handlers written in C.
     (Andy Lutomirski)

   - vm86 mode cleanups and fixes.  (Brian Gerst)

   - 32-bit compat code cleanups.  (Brian Gerst)

  The amount of simplification in low level assembly code is already
  palpable:

     arch/x86/entry/entry_32.S                          | 130 +----
     arch/x86/entry/entry_64.S                          | 197 ++-----

  but more simplifications are planned.

  There's also the usual laudry mix of low level changes - see the
  changelog for details"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (83 commits)
  x86/asm: Drop repeated macro of X86_EFLAGS_AC definition
  x86/asm/msr: Make wrmsrl() a function
  x86/asm/delay: Introduce an MWAITX-based delay with a configurable timer
  x86/asm: Add MONITORX/MWAITX instruction support
  x86/traps: Weaken context tracking entry assertions
  x86/asm/tsc: Add rdtscll() merge helper
  selftests/x86: Add syscall_nt selftest
  selftests/x86: Disable sigreturn_64
  x86/vdso: Emit a GNU hash
  x86/entry: Remove do_notify_resume(), syscall_trace_leave(), and their TIF masks
  x86/entry/32: Migrate to C exit path
  x86/entry/32: Remove 32-bit syscall audit optimizations
  x86/vm86: Rename vm86->v86flags and v86mask
  x86/vm86: Rename vm86->vm86_info to user_vm86
  x86/vm86: Clean up vm86.h includes
  x86/vm86: Move the vm86 IRQ definitions to vm86.h
  x86/vm86: Use the normal pt_regs area for vm86
  x86/vm86: Eliminate 'struct kernel_vm86_struct'
  x86/vm86: Move fields from 'struct kernel_vm86_struct' to 'struct vm86'
  x86/vm86: Move vm86 fields out of 'thread_struct'
  ...
2015-09-01 08:40:25 -07:00
Rafael J. Wysocki
56963d99b7 Merge branches 'pm-sleep', 'pm-domains' and 'pm-avs'
* pm-sleep:
  PM / suspend: make sync() on suspend-to-RAM build-time optional
  PM / sleep: Allow devices without runtime PM to do direct-complete
  PM / autosleep: Use workqueue for user space wakeup sources garbage collector

* pm-domains:
  PM / Domains: Fix typo in description of genpd_dev_pm_detach()
  PM / Domains: Remove unusable governor dummies
  PM / Domains: Make pm_genpd_init() available to modules
  PM / domains: Align column headers and data in pm_genpd_summary output
  PM / Domains: Return -EPROBE_DEFER if we fail to init or turn-on domain
  PM / Domains: Correct unit address in power-controller example
  PM / Domains: Remove intermediate states from the power off sequence

* pm-avs:
  PM / AVS: rockchip-io: add io selectors and supplies for rk3368
  PM / AVS: rockchip-io: depend on CONFIG_POWER_AVS
2015-09-01 15:54:20 +02:00
Linus Torvalds
65a99597f0 Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull NOHZ updates from Ingo Molnar:
 "The main changes, mostly written by Frederic Weisbecker, include:

   - Fix some jiffies based cputime assumptions.  (No real harm because
     the concerned code isn't used by full dynticks.)

   - Simplify jiffies <-> usecs conversions.  Remove dead code.

   - Remove early hacks on nohz full code that avoided messing up idle
     nohz internals.  Now nohz integrates well full and idle and such
     hack have become needless.

   - Restart nohz full tick from irq exit.  (A simplification and a
     preparation for future optimization on scheduler kick to nohz
     full)

   - Code cleanups.

   - Tile driver isolation enhancement on top of nohz.  (Chris Metcalf)"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  nohz: Remove useless argument on tick_nohz_task_switch()
  nohz: Move tick_nohz_restart_sched_tick() above its users
  nohz: Restart nohz full tick from irq exit
  nohz: Remove idle task special case
  nohz: Prevent tilegx network driver interrupts
  alpha: Fix jiffies based cputime assumption
  apm32: Fix cputime == jiffies assumption
  jiffies: Remove HZ > USEC_PER_SEC special case
2015-08-31 21:04:24 -07:00
Linus Torvalds
418c2e1f67 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Ingo Molnar:
 "This is a leftover scheduler fix from the v4.2 cycle"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix cpu_active_mask/cpu_online_mask race
2015-08-31 20:55:23 -07:00
Linus Torvalds
a1d8561172 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The biggest change in this cycle is the rewrite of the main SMP load
  balancing metric: the CPU load/utilization.  The main goal was to make
  the metric more precise and more representative - see the changelog of
  this commit for the gory details:

    9d89c257df ("sched/fair: Rewrite runnable load and utilization average tracking")

  It is done in a way that significantly reduces complexity of the code:

    5 files changed, 249 insertions(+), 494 deletions(-)

  and the performance testing results are encouraging.  Nevertheless we
  need to keep an eye on potential regressions, since this potentially
  affects every SMP workload in existence.

  This work comes from Yuyang Du.

  Other changes:

   - SCHED_DL updates.  (Andrea Parri)

   - Simplify architecture callbacks by removing finish_arch_switch().
     (Peter Zijlstra et al)

   - cputime accounting: guarantee stime + utime == rtime.  (Peter
     Zijlstra)

   - optimize idle CPU wakeups some more - inspired by Facebook server
     loads.  (Mike Galbraith)

   - stop_machine fixes and updates.  (Oleg Nesterov)

   - Introduce the 'trace_sched_waking' tracepoint.  (Peter Zijlstra)

   - sched/numa tweaks.  (Srikar Dronamraju)

   - misc fixes and small cleanups"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  sched/deadline: Fix comment in enqueue_task_dl()
  sched/deadline: Fix comment in push_dl_tasks()
  sched: Change the sched_class::set_cpus_allowed() calling context
  sched: Make sched_class::set_cpus_allowed() unconditional
  sched: Fix a race between __kthread_bind() and sched_setaffinity()
  sched: Ensure a task has a non-normalized vruntime when returning back to CFS
  sched/numa: Fix NUMA_DIRECT topology identification
  tile: Reorganize _switch_to()
  sched, sparc32: Update scheduler comments in copy_thread()
  sched: Remove finish_arch_switch()
  sched, tile: Remove finish_arch_switch
  sched, sh: Fold finish_arch_switch() into switch_to()
  sched, score: Remove finish_arch_switch()
  sched, avr32: Remove finish_arch_switch()
  sched, MIPS: Get rid of finish_arch_switch()
  sched, arm: Remove finish_arch_switch()
  sched/fair: Clean up load average references
  sched/fair: Provide runnable_load_avg back to cfs_rq
  sched/fair: Remove task and group entity load when they are dead
  sched/fair: Init cfs_rq's sched_entity load average
  ...
2015-08-31 20:26:22 -07:00
Linus Torvalds
41d859a83c Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Main perf kernel side changes:

   - uprobes updates/fixes.  (Oleg Nesterov)

   - Add PERF_RECORD_SWITCH to indicate context switches and use it in
     tooling.  (Adrian Hunter)

   - Support BPF programs attached to uprobes and first steps for BPF
     tooling support.  (Wang Nan)

   - x86 generic x86 MSR-to-perf PMU driver.  (Andy Lutomirski)

   - x86 Intel PT, LBR and BTS updates.  (Alexander Shishkin)

   - x86 Intel Skylake support.  (Andi Kleen)

   - x86 Intel Knights Landing (KNL) RAPL support.  (Dasaratharaman
     Chandramouli)

   - x86 Intel Broadwell-DE uncore support.  (Kan Liang)

   - x86 hw breakpoints robustization (Andy Lutomirski)

  Main perf tooling side changes:

   - Support Intel PT in several tools, enabling the use of the
     processor trace feature introduced in Intel Broadwell processors:
     (Adrian Hunter)

       # dmesg | grep Performance
       # [0.188477] Performance Events: PEBS fmt2+, 16-deep LBR, Broadwell events, full-width counters, Intel PMU driver.
       # perf record -e intel_pt//u -a sleep 1
       [ perf record: Woken up 1 times to write data ]
       [ perf record: Captured and wrote 0.216 MB perf.data ]
       # perf script # then navigate in the tool output to some area, like this one:
       184 1030 dl_main (/usr/lib64/ld-2.17.so) => 7f21ba661440 dl_main (/usr/lib64/ld-2.17.so)
       185 1457 dl_main (/usr/lib64/ld-2.17.so) => 7f21ba669f10 _dl_new_object (/usr/lib64/ld-2.17.so)
       186 9f37 _dl_new_object (/usr/lib64/ld-2.17.so) => 7f21ba677b90 strlen (/usr/lib64/ld-2.17.so)
       187 7ba3 strlen (/usr/lib64/ld-2.17.so) => 7f21ba677c75 strlen (/usr/lib64/ld-2.17.so)
       188 7c78 strlen (/usr/lib64/ld-2.17.so) => 7f21ba669f3c _dl_new_object (/usr/lib64/ld-2.17.so)
       189 9f8a _dl_new_object (/usr/lib64/ld-2.17.so) => 7f21ba65fab0 calloc@plt (/usr/lib64/ld-2.17.so)
       190 fab0 calloc@plt (/usr/lib64/ld-2.17.so) => 7f21ba675e70 calloc (/usr/lib64/ld-2.17.so)
       191 5e87 calloc (/usr/lib64/ld-2.17.so) => 7f21ba65fa90 malloc@plt (/usr/lib64/ld-2.17.so)
       192 fa90 malloc@plt (/usr/lib64/ld-2.17.so) => 7f21ba675e60 malloc (/usr/lib64/ld-2.17.so)
       193 5e68 malloc (/usr/lib64/ld-2.17.so) => 7f21ba65fa80 __libc_memalign@plt (/usr/lib64/ld-2.17.so)
       194 fa80 __libc_memalign@plt (/usr/lib64/ld-2.17.so) => 7f21ba675d50 __libc_memalign (/usr/lib64/ld-2.17.so)
       195 5d63 __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba675e20 __libc_memalign (/usr/lib64/ld-2.17.so)
       196 5e40 __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba675d73 __libc_memalign (/usr/lib64/ld-2.17.so)
       197 5d97 __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba675e18 __libc_memalign (/usr/lib64/ld-2.17.so)
       198 5e1e __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba675df9 __libc_memalign (/usr/lib64/ld-2.17.so)
       199 5e10 __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba669f8f _dl_new_object (/usr/lib64/ld-2.17.so)
       200 9fc2 _dl_new_object (/usr/lib64/ld-2.17.so) =>  7f21ba678e70 memcpy (/usr/lib64/ld-2.17.so)
       201 8e8c memcpy (/usr/lib64/ld-2.17.so) => 7f21ba678ea0 memcpy (/usr/lib64/ld-2.17.so)

   - Add support for using several Intel PT features (CYC, MTC packets),
     the relevant documentation was updated in:
         tools/perf/Documentation/intel-pt.txt
     briefly describing those packets, its purposes, how to configure
     them in the event config terms and relevant external documentation
     for further reading.  (Adrian Hunter)

   - Introduce support for probing at an absolute address, for user and
     kernel 'perf probe's, useful when one have the symbol maps on a
     developer machine but not on an embedded system.  (Wang Nan)

   - Add Intel BTS support, with a call-graph script to show it and PT
     in use in a GUI using 'perf script' python scripting with
     postgresql and Qt.  (Adrian Hunter)

   - Allow selecting the type of callchains per event, including
     disabling callchains in all but one entry in an event list, to save
     space, and also to ask for the callchains collected in one event to
     be used in other events.  (Kan Liang)

   - Beautify more syscall arguments in 'perf trace': (Arnaldo Carvalho
     de Melo)
       * A bunch more translate file/pathnames from pointers to strings.
       * Convert numbers to strings for the 'keyctl' syscall 'option'
         arg.
       * Add missing 'clockid' entries.

   - Introduce 'srcfile' sort key: (Andi Kleen)

       # perf record -F 10000 usleep 1
       # perf report --stdio --dsos '[kernel.vmlinux]' -s srcfile
       <SNIP>
       # Overhead  Source File
          26.49%  copy_page_64.S
           5.49%  signal.c
           0.51%  msr.h
       #

     It can be combined with other fields, for instance, experiment with
     '-s srcfile,symbol'.

     There are some oddities in some distros and with some specific
     DSOs, being investigated, so your mileage may vary.

   - Support per-event 'freq' term: (Namhyung Kim)

       $ perf record -e 'cpu/instructions,freq=1234/',cycles -c 1000 sleep 1
       $ perf evlist -F
       cpu/instructions,freq=1234/: sample_freq=1234
       cycles: sample_period=1000
       $

   - Deref sys_enter pointer args with contents from probe:vfs_getname,
     showing pathnames instead of pointers in many syscalls in 'perf
     trace'.  (Arnaldo Carvalho de Melo)

   - Stop collecting /proc/kallsyms in perf.data files, saving about
     4.5MB on a typical x86-64 system, use the the symbol resolution
     routines used in all the other tools (report, top, etc) now that we
     can ask libtraceevent to use perf's symbol resolution code.
     (Arnaldo Carvalho de Melo)

   - Allow filtering out of perf's PID via 'perf record --exclude-perf'.
     (Wang Nan)

   - 'perf trace' now supports syscall groups, like strace, i.e:

       $ trace -e file touch file

     Will expand 'file' into multiple, file related, syscalls.  More
     work needed to add extra groups for other syscall groups, and also
     to complement what was added for the 'file' group, included as a
     proof of concept.  (Arnaldo Carvalho de Melo)

   - Add lock_pi stresser to 'perf bench futex', to test the kernel code
     related to FUTEX_(UN)LOCK_PI.  (Davidlohr Bueso)

   - Let user have timestamps with per-thread recording in 'perf record'
     (Adrian Hunter)

   - ... and tons of other changes, see the shortlog and the Git log for
     details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (240 commits)
  perf evlist: Add backpointer for perf_env to evlist
  perf tools: Rename perf_session_env to perf_env
  perf tools: Do not change lib/api/fs/debugfs directly
  perf tools: Add tracing_path and remove unneeded functions
  perf buildid: Introduce sysfs/filename__sprintf_build_id
  perf evsel: Add a backpointer to the evlist a evsel is in
  perf trace: Add header with copyright and background info
  perf scripts python: Add new compaction-times script
  perf stat: Get correct cpu id for print_aggr
  tools lib traceeveent: Allow for negative numbers in print format
  perf script: Add --[no-]-demangle/--[no-]-demangle-kernel
  tracing/uprobes: Do not print '0x (null)' when offset is 0
  perf probe: Support probing at absolute address
  perf probe: Fix error reported when offset without function
  perf probe: Fix list result when address is zero
  perf probe: Fix list result when symbol can't be found
  tools build: Allow duplicate objects in the object list
  perf tools: Remove export.h from MANIFEST
  perf probe: Prevent segfault when reading probe point with absolute address
  perf tools: Update Intel PT documentation
  ...
2015-08-31 19:49:05 -07:00
Linus Torvalds
7073bc6612 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this cycle are:

   - the combination of tree geometry-initialization simplifications and
     OS-jitter-reduction changes to expedited grace periods.  These two
     are stacked due to the large number of conflicts that would
     otherwise result.

   - privatize smp_mb__after_unlock_lock().

     This commit moves the definition of smp_mb__after_unlock_lock() to
     kernel/rcu/tree.h, in recognition of the fact that RCU is the only
     thing using this, that nothing else is likely to use it, and that
     it is likely to go away completely.

   - documentation updates.

   - torture-test updates.

   - misc fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
  rcu,locking: Privatize smp_mb__after_unlock_lock()
  rcu: Silence lockdep false positive for expedited grace periods
  rcu: Don't disable CPU hotplug during OOM notifiers
  scripts: Make checkpatch.pl warn on expedited RCU grace periods
  rcu: Update MAINTAINERS entry
  rcu: Clarify CONFIG_RCU_EQS_DEBUG help text
  rcu: Fix backwards RCU_LOCKDEP_WARN() in synchronize_rcu_tasks()
  rcu: Rename rcu_lockdep_assert() to RCU_LOCKDEP_WARN()
  rcu: Make rcu_is_watching() really notrace
  cpu: Wait for RCU grace periods concurrently
  rcu: Create a synchronize_rcu_mult()
  rcu: Fix obsolete priority-boosting comment
  rcu: Use WRITE_ONCE in RCU_INIT_POINTER
  rcu: Hide RCU_NOCB_CPU behind RCU_EXPERT
  rcu: Add RCU-sched flavors of get-state and cond-sync
  rcu: Add fastpath bypassing funnel locking
  rcu: Rename RCU_GP_DONE_FQS to RCU_GP_DOING_FQS
  rcu: Pull out wait_event*() condition into helper function
  documentation: Describe new expedited stall warnings
  rcu: Add stall warnings to synchronize_sched_expedited()
  ...
2015-08-31 18:12:07 -07:00
Linus Torvalds
1af115d675 Driver core patches for 4.3-rc1
Here is the new patches for the driver core / sysfs for 4.3-rc1.
 
 Very small number of changes here, all the details are in the shortlog,
 nothing major happening at all this kernel release, which is nice to
 see.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iEYEABECAAYFAlXV9EwACgkQMUfUDdst+ylv1ACgj7srYyvumehX1zfRVzEWNuez
 chQAoKHnSpDMME/WmhQQRxzQ5pfd1Pni
 =uGHg
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the new patches for the driver core / sysfs for 4.3-rc1.

  Very small number of changes here, all the details are in the
  shortlog, nothing major happening at all this kernel release, which is
  nice to see"

* tag 'driver-core-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  bus: subsys: update return type of ->remove_dev() to void
  driver core: correct device's shutdown order
  driver core: fix docbook for device_private.device
  selftests: firmware: skip timeout checks for kernels without user mode helper
  kernel, cpu: Remove bogus __ref annotations
  cpu: Remove bogus __ref annotation of cpu_subsys_online()
  firmware: fix wrong memory deallocation in fw_add_devm_name()
  sysfs.txt: update show method notes about sprintf/snprintf/scnprintf usage
  devres: fix devres_get()
2015-08-31 08:47:40 -07:00
Linus Torvalds
1c00038c76 Char/Misc driver patches for 4.3-rc1
Here's the "big" char/misc driver update for 4.3-rc1.
 
 Not much really interesting here, just a number of little changes all
 over the place, and some nice consolidation of the nvmem drivers to a
 common framework.  As usual, the mei drivers stand out as the largest
 "churn" to handle new devices and features in their hardware.
 
 All have been in linux-next for a while with no issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iEYEABECAAYFAlXV844ACgkQMUfUDdst+ymYfQCgmDKjq3fsVHCxNZPxnukFYzvb
 xZkAnRb8fuub5gVQFP29A+rhyiuWD13v
 =Bq9K
 -----END PGP SIGNATURE-----

Merge tag 'char-misc-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver patches from Greg KH:
 "Here's the "big" char/misc driver update for 4.3-rc1.

  Not much really interesting here, just a number of little changes all
  over the place, and some nice consolidation of the nvmem drivers to a
  common framework.  As usual, the mei drivers stand out as the largest
  "churn" to handle new devices and features in their hardware.

  All have been in linux-next for a while with no issues"

* tag 'char-misc-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (136 commits)
  auxdisplay: ks0108: initialize local parport variable
  extcon: palmas: Fix build break due to devm_gpiod_get_optional API change
  extcon: palmas: Support GPIO based USB ID detection
  extcon: Fix signedness bugs about break error handling
  extcon: Drop owner assignment from i2c_driver
  extcon: arizona: Simplify pdata symantics for micd_dbtime
  extcon: arizona: Declare 3-pole jack if we detect open circuit on mic
  extcon: Add exception handling to prevent the NULL pointer access
  extcon: arizona: Ensure variables are set for headphone detection
  extcon: arizona: Use gpiod inteface to handle micd_pol_gpio gpio
  extcon: arizona: Add basic microphone detection DT/ACPI bindings
  extcon: arizona: Update to use the new device properties API
  extcon: palmas: Remove the mutually_exclusive array
  extcon: Remove optional print_state() function pointer of struct extcon_dev
  extcon: Remove duplicate header file in extcon.h
  extcon: max77843: Clear IRQ bits state before request IRQ
  toshiba laptop: replace ioremap_cache with ioremap
  misc: eeprom: max6875: clean up max6875_read()
  misc: eeprom: clean up eeprom_read()
  misc: eeprom: 93xx46: clean up eeprom_93xx46_bin_read/write
  ...
2015-08-31 08:34:13 -07:00
Ingo Molnar
02b643b643 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-31 10:25:26 +02:00
Alexei Starovoitov
8d3b7dce86 bpf: add support for %s specifier to bpf_trace_printk()
%s specifier makes bpf program and kernel debugging easier.
To make sure that trace_printk won't crash the unsafe string
is copied into stack and unsafe pointer is substituted.

The following C program:
 #include <linux/fs.h>
int foo(struct pt_regs *ctx, struct filename *filename)
{
  void *name = 0;

  bpf_probe_read(&name, sizeof(name), &filename->name);
  bpf_trace_printk("executed %s\n", name);
  return 0;
}

when attached to kprobe do_execve()
will produce output in /sys/kernel/debug/tracing/trace_pipe :
    make-13492 [002] d..1  3250.997277: : executed /bin/sh
      sh-13493 [004] d..1  3250.998716: : executed /usr/bin/gcc
     gcc-13494 [002] d..1  3250.999822: : executed /usr/lib/gcc/x86_64-linux-gnu/4.7/cc1
     gcc-13495 [002] d..1  3251.006731: : executed /usr/bin/as
     gcc-13496 [002] d..1  3251.011831: : executed /usr/lib/gcc/x86_64-linux-gnu/4.7/collect2
collect2-13497 [000] d..1  3251.012941: : executed /usr/bin/ld

Suggested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28 16:27:27 -07:00
Alexei Starovoitov
1a6877b9c0 lib: introduce strncpy_from_unsafe()
generalize FETCH_FUNC_NAME(memory, string) into
strncpy_from_unsafe() and fix sparse warnings that were
present in original implementation.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28 16:27:27 -07:00
David S. Miller
0d36938bb8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-08-27 21:45:31 -07:00
Christoph Hellwig
41e94a8513 add devm_memremap_pages
This behaves like devm_memremap except that it ensures we have page
structures available that can back the region.

Signed-off-by: Christoph Hellwig <hch@lst.de>
[djbw: catch attempts to remap RAM, drop flags]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-27 19:40:58 -04:00
Wang Nan
a2fb3382ed tracing/uprobes: Do not print '0x (null)' when offset is 0
When manually added uprobe point with zero address, 'uprobe_events'
output '(null)' instead of 0x00000000:

  # echo p:probe_libc/abs_0 /path/to/lib.bin:0x0 arg1=%ax > \
            /sys/kernel/debug/tracing/uprobe_events

  # cat /sys/kernel/debug/tracing/uprobe_events
    p:probe_libc/abs_0 /path/to/lib.bin:0x          (null) arg1=%ax

 This patch fixes this behavior:

  # cat /sys/kernel/debug/tracing/uprobe_events
  p:probe_libc/abs_0 /path/to/lib.bin:0x0000000000000000

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-8-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-26 10:43:01 -03:00
Tejun Heo
20f1f4b5ff Merge branch 'for-4.3-unified-base' into for-4.3 2015-08-25 14:19:29 -04:00
Aleksa Sarai
ce52399520 cgroup: pids: fix invalid get/put usage
Fix incorrect usage of css_get and css_put to put a different css in
pids_{cancel_,}attach() than the one grabbed in pids_can_attach(). This
could lead to quite serious memory leakage (and unsafe operations on the
putted css).

tj: minor comment update

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2015-08-25 14:19:25 -04:00
Jan H. Schönherr
dd9d384375 sched: Fix cpu_active_mask/cpu_online_mask race
There is a race condition in SMP bootup code, which may result
in

    WARNING: CPU: 0 PID: 1 at kernel/workqueue.c:4418
    workqueue_cpu_up_callback()
or
    kernel BUG at kernel/smpboot.c:135!

It can be triggered with a bit of luck in Linux guests running
on busy hosts.

	CPU0                        CPUn
	====                        ====

	_cpu_up()
	  __cpu_up()
				    start_secondary()
				      set_cpu_online()
					cpumask_set_cpu(cpu,
						   to_cpumask(cpu_online_bits));
	  cpu_notify(CPU_ONLINE)
	    <do stuff, see below>
					cpumask_set_cpu(cpu,
						   to_cpumask(cpu_active_bits));

During the various CPU_ONLINE callbacks CPUn is online but not
active. Several things can go wrong at that point, depending on
the scheduling of tasks on CPU0.

Variant 1:

  cpu_notify(CPU_ONLINE)
    workqueue_cpu_up_callback()
      rebind_workers()
        set_cpus_allowed_ptr()

  This call fails because it requires an active CPU; rebind_workers()
  ends with a warning:

    WARNING: CPU: 0 PID: 1 at kernel/workqueue.c:4418
    workqueue_cpu_up_callback()

Variant 2:

  cpu_notify(CPU_ONLINE)
    smpboot_thread_call()
      smpboot_unpark_threads()
       ..
        __kthread_unpark()
          __kthread_bind()
          wake_up_state()
           ..
            select_task_rq()
              select_fallback_rq()

  The ->wake_cpu of the unparked thread is not allowed, making a call
  to select_fallback_rq() necessary. Then, select_fallback_rq() cannot
  find an allowed, active CPU and promptly resets the allowed CPUs, so
  that the task in question ends up on CPU0.

  When those unparked tasks are eventually executed, they run
  immediately into a BUG:

    kernel BUG at kernel/smpboot.c:135!

Just changing the order in which the online/active bits are set
(and adding some memory barriers), would solve the two issues
above. However, it would change the order of operations back to
the one before commit 6acbfb9697 ("sched: Fix hotplug vs.
set_cpus_allowed_ptr()"), thus, reintroducing that particular
problem.

Going further back into history, we have at least the following
commits touching this topic:
- commit 2baab4e904 ("sched: Fix select_fallback_rq() vs cpu_active/cpu_online")
- commit 5fbd036b55 ("sched: Cleanup cpu_active madness")

Together, these give us the following non-working solutions:

  - secondary CPU sets active before online, because active is assumed to
    be a subset of online;

  - secondary CPU sets online before active, because the primary CPU
    assumes that an online CPU is also active;

  - secondary CPU sets online and waits for primary CPU to set active,
    because it might deadlock.

Commit 875ebe940d ("powerpc/smp: Wait until secondaries are
active & online") introduces an arch-specific solution to this
arch-independent problem.

Now, go for a more general solution without explicit waiting and
simply set active twice: once on the secondary CPU after online
was set and once on the primary CPU after online was seen.

set_cpus_allowed_ptr()")

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@vger.kernel.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Wilson <msw@amazon.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 6acbfb9697 ("sched: Fix hotplug vs. set_cpus_allowed_ptr()")
Link: http://lkml.kernel.org/r/1439408156-18840-1-git-send-email-jschoenh@amazon.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-25 12:14:39 +02:00
Ingo Molnar
f612a7b1a7 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU cleanup from Paul E. McKenney:

 "Privatize smp_mb__after_unlock_lock().  This commit moves the
  definition of smp_mb__after_unlock_lock() to kernel/rcu/tree.h,
  in recognition of the fact that RCU is the only thing using
  this, that nothing else is likely to use it, and that it is
  likely to go away completely."

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-25 09:44:49 +02:00
Linus Torvalds
84f3fe4608 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "A series of small fixlets for a regression visible on OMAP devices
  caused by the conversion of the OMAP interrupt chips to hierarchical
  interrupt domains.  Mostly one liners on the driver side plus a small
  helper function in the core to avoid open coded mess in the drivers"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/crossbar: Restore set_wake functionality
  irqchip/crossbar: Restore the mask on suspend behaviour
  ARM: OMAP: wakeupgen: Restore the irq_set_type() mechanism
  irqchip/crossbar: Restore the irq_set_type() mechanism
  genirq: Introduce irq_chip_set_type_parent() helper
  genirq: Don't return ENOSYS in irq_chip_retrigger_hierarchy
2015-08-22 07:45:36 -07:00
Linus Torvalds
f8a89fc05a Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "Two minimalistic fixes for 4.2 regressions:

   - Eric fixed a thinko in the timer_list base switching code caused by
     the overhaul of the timer wheel.  It can cause a cpu to see the
     wrong base for a timer while we move the timer around.

   - Guenter fixed a regression for IMX if booted w/o device tree, where
     the timer interrupt is not initialized and therefor the machine
     fails to boot"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/imx: Fix boot with non-DT systems
  timer: Write timer->flags atomically
2015-08-22 07:37:41 -07:00
Guenter Roeck
85e1cd6e76 hrtimer: Handle failure of tick_init_highres() gracefully
Commit 75e3b37d05 ("hrtimer: Drop return code of hrtimer_switch_to_hres()")
drops the return code of hrtimer_switch_to_hres(). While doing so, it also
drops the return statement itself on failure. This may cause a system hang.
Seen when running arm:multi_v7_defconfig in qemu with devicetree file
vexpress-v2p-ca9.

Fixes: 75e3b37d05 ("hrtimer: Drop return code of hrtimer_switch_to_hres()")
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/1440231047-16256-1-git-send-email-linux@roeck-us.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-22 10:57:50 +02:00
David S. Miller
dc25b25897 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/qmi_wwan.c

Overlapping additions of new device IDs to qmi_wwan.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-21 11:44:04 -07:00
Thomas Gleixner
05ddaa4d6d Merge branch 'fortglx/4.3/time' of https://git.linaro.org/people/john.stultz/linux into timers/core
- A handful or y2038 related items
- A walltime to monotonic limit
- Small fixes for timespec_trunc() and timer_list output
2015-08-20 21:13:22 +02:00
Ingo Molnar
40a2ea1bd9 Merge branch 'perf/urgent' into perf/core, to pick up fixes before adding more changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-20 11:48:56 +02:00
Grygorii Strashko
b7560de198 genirq: Introduce irq_chip_set_type_parent() helper
This helper is required for irq chips which do not implement a
irq_set_type callback and need to call down the irq domain hierarchy
for the actual trigger type change.

This helper is required to fix further wreckage caused by the
conversion of TI OMAP to hierarchical irq domains and therefor tagged
for stable.

[ tglx: Massaged changelog ]

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: <linux@arm.linux.org.uk>
Cc: <nsekhar@ti.com>
Cc: <jason@lakedaemon.net>
Cc: <balbi@ti.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: <tony@atomide.com>
Cc: <marc.zyngier@arm.com>
Cc: stable@vger.kernel.org # 4.1
Link: http://lkml.kernel.org/r/1439554830-19502-3-git-send-email-grygorii.strashko@ti.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-20 00:25:25 +02:00
Grygorii Strashko
6d4affea7d genirq: Don't return ENOSYS in irq_chip_retrigger_hierarchy
irq_chip_retrigger_hierarchy() returns -ENOSYS if it was not able to
find at least one .irq_retrigger() callback implemented in the IRQ
domain hierarchy.

That's wrong, because check_irq_resend() expects a 0 return value from
the callback in case that the hardware assisted resend was not
possible. If the return value is non zero the core code assumes
hardware resend success and the software resend is not invoked.

This results in lost interrupts on platforms where none of the parent
irq chips in the hierarchy implements the retrigger callback.

This is observable on TI OMAP, where the hierarchy is:

 ARM GIC <- OMAP wakeupgen <- TI Crossbar

Return 0 instead so the software resend mechanism gets invoked.

[ tglx: Massaged changelog ]

Fixes: 85f08c17de ('genirq: Introduce helper functions...')
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: <linux@arm.linux.org.uk>
Cc: <nsekhar@ti.com>
Cc: <jason@lakedaemon.net>
Cc: <balbi@ti.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: <tony@atomide.com>
Cc: stable@vger.kernel.org # 4.1
Link: http://lkml.kernel.org/r/1439554830-19502-2-git-send-email-grygorii.strashko@ti.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-20 00:25:25 +02:00
Tejun Heo
3e1d2eed39 cgroup: introduce cgroup_subsys->legacy_name
This allows cgroup subsystems to use a different name on the unified
hierarchy.  cgroup_subsys->name is used on the unified hierarchy,
->legacy_name elsewhere.  If ->legacy_name is not explicitly set, it's
automatically set to ->name and the userland visible behavior remains
unchanged.

v2: Make parse_cgroupfs_options() only consider ->legacy_name as mount
    options are used only on legacy hierarchies.  Suggested by Li
    Zefan.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: cgroups@vger.kernel.org
2015-08-18 13:58:16 -07:00
Tejun Heo
d98817d496 cgroup: don't print subsystems for the default hierarchy
It doesn't make sense to print subsystems on mount option or
/proc/PID/cgroup for the default hierarchy.

* cgroup.controllers file at the root of the default hierarchy lists
  the currently attached controllers.

* The default hierarchy is catch-all for unmounted subsystems.

* The default hierarchy doesn't accept any mount options.

Suppress subsystem printing on mount options and /proc/PID/cgroup for
the default hierarchy.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: cgroups@vger.kernel.org
2015-08-18 13:58:16 -07:00
Frederic Weisbecker
b48362d8aa hrtimer: Unconfuse switch_hrtimer_base() a bit
The variable called "this_base" is confusing because its name suggests
it's of "struct hrtimer_clock_base" type, along with "base" and "new_base"
which doesn't help understanding this complicated function.

Make its name clearer and fix the misleading comment while at it.

[ tglx: Fixed the comment for real ]

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1439907509-9553-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-18 18:36:59 +02:00
Frederic Weisbecker
662b3e1946 hrtimer: Simplify get_target_base() by returning current base
Instead of fetching again the current cpu base, just take it from the
parameter.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1439907509-9553-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-18 18:36:59 +02:00
Eric Dumazet
d0023a1448 timer: Write timer->flags atomically
lock_timer_base() cannot prevent the following :

CPU1 ( in __mod_timer()
timer->flags |= TIMER_MIGRATING;
spin_unlock(&base->lock);
base = new_base;
spin_lock(&base->lock);
// The next line clears TIMER_MIGRATING
timer->flags &= ~TIMER_BASEMASK;
                                  CPU2 (in lock_timer_base())
                                  see timer base is cpu0 base
                                  spin_lock_irqsave(&base->lock, *flags);
                                  if (timer->flags == tf)
                                       return base; // oops, wrong base
timer->flags |= base->cpu // too late

We must write timer->flags in one go, otherwise we can fool other cpus.

Fixes: bc7a34b8b9 ("timer: Reduce timer migration overhead if disabled")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jon Christopherson <jon@jons.org>
Cc: David Miller <davem@davemloft.net>
Cc: xen-devel@lists.xen.org
Cc: david.vrabel@citrix.com
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Link: http://lkml.kernel.org/r/1439831928.32680.11.camel@edumazet-glaptop2.roam.corp.google.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
2015-08-18 15:31:16 +02:00
Ingo Molnar
a5dd192496 Merge branch 'x86/urgent' into x86/asm to fix up conflicts and to pick up fixes
Conflicts:
	arch/x86/entry/entry_64_compat.S
	arch/x86/math-emu/get_address.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-18 09:39:47 +02:00
Linus Torvalds
e9ab22d292 Merge branch 'for-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
 "A fix for a subtle bug introduced back during 3.17 cycle which
  interferes with setting configurations under specific conditions"

* 'for-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cpuset: use trialcs->mems_allowed as a temp variable
2015-08-17 16:15:26 -07:00
Luiz Capitulino
75e3b37d05 hrtimer: Drop return code of hrtimer_switch_to_hres()
It's not checked by the caller.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Link: http://lkml.kernel.org/r/20150811164043.538241ef@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-17 23:19:03 +02:00
Baolin Wang
9ca3085060 time: Introduce timespec64_to_jiffies()/jiffies_to_timespec64()
The conversion between struct timespec and jiffies is not year 2038
safe on 32bit systems. Introduce timespec64_to_jiffies() and
jiffies_to_timespec64() functions which use struct timespec64 to
make it ready for 2038 issue.

Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-08-17 11:25:41 -07:00
Baolin Wang
8758a240e2 time: Introduce current_kernel_time64()
The current_kernel_time() is not year 2038 safe on 32bit systems
since it returns a timespec value. Introduce current_kernel_time64()
which returns a timespec64 value.

Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-08-17 11:25:35 -07:00
Xunlei Pang
7494e9eede time: Add the common weak version of update_persistent_clock()
The weak update_persistent_clock64() calls update_persistent_clock(),
if the architecture defines an update_persistent_clock64() to replace
and remove its update_persistent_clock() version, when building the
kernel the linker will throw an undefined symbol error, that is, any
arch that switches to update_persistent_clock64() will have this issue.

To solve the issue, we add the common weak update_persistent_clock().

Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-08-17 11:25:16 -07:00
Wang YanQing
e1d7ba8735 time: Always make sure wall_to_monotonic isn't positive
Two issues were found on an IMX6 development board without an
enabled RTC device(resulting in the boot time and monotonic
time being initialized to 0).

Issue 1:exportfs -a generate:
       "exportfs: /opt/nfs/arm does not support NFS export"
Issue 2:cat /proc/stat:
       "btime 4294967236"

The same issues can be reproduced on x86 after running the
following code:
	int main(void)
	{
	    struct timeval val;
	    int ret;

	    val.tv_sec = 0;
	    val.tv_usec = 0;
	    ret = settimeofday(&val, NULL);
	    return 0;
	}

Two issues are different symptoms of same problem:
The reason is a positive wall_to_monotonic pushes boot time back
to the time before Epoch, and getboottime will return negative
value.

In symptom 1:
          negative boot time cause get_expiry() to overflow time_t
          when input expire time is 2147483647, then cache_flush()
          always clears entries just added in ip_map_parse.
In symptom 2:
          show_stat() uses "unsigned long" to print negative btime
          value returned by getboottime.

This patch fix the problem by prohibiting time from being set to a value which
would cause a negative boot time. As a result one can't set the CLOCK_REALTIME
time prior to (1970 + system uptime).

Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Wang YanQing <udknight@gmail.com>
[jstultz: reworded commit message]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-08-17 11:24:54 -07:00
Karsten Blees
de4a95faf1 time: Fix nanosecond file time rounding in timespec_trunc()
timespec_trunc() avoids rounding if granularity <= nanoseconds-per-jiffie
(or TICK_NSEC). This optimization assumes that:

 1. current_kernel_time().tv_nsec is already rounded to TICK_NSEC (i.e.
    with HZ=1000 you'd get 1000000, 2000000, 3000000... but never 1000001).
    This is no longer true (probably since hrtimers introduced in 2.6.16).

 2. TICK_NSEC is evenly divisible by all possible granularities. This may
    be true for HZ=100, 250, 1000, but obviously not for HZ=300 /
    TICK_NSEC=3333333 (introduced in 2.6.20).

Thus, sub-second portions of in-core file times are not rounded to on-disk
granularity. I.e. file times may change when the inode is re-read from disk
or when the file system is remounted.

This affects all file systems with file time granularities > 1 ns and < 1s,
e.g. CEPH (1000 ns), UDF (1000 ns), CIFS (100 ns), NTFS (100 ns) and FUSE
(configurable from user mode via struct fuse_init_out.time_gran).

Steps to reproduce with e.g. UDF:

  $ dd if=/dev/zero of=udfdisk count=10000 && mkudffs udfdisk
  $ mkdir udf && mount udfdisk udf
  $ touch udf/test && stat -c %y udf/test
  2015-06-09 10:22:56.130006767 +0200
  $ umount udf && mount udfdisk udf
  $ stat -c %y udf/test
  2015-06-09 10:22:56.130006000 +0200

Remounting truncates the mtime to 1 µs.

Fix the rounding in timespec_trunc() and update the documentation.

timespec_trunc() is exclusively used to calculate inode's [acm]time (mostly
via current_fs_time()), and always with super_block.s_time_gran as second
argument. So this can safely be changed without side effects.

Note: This does _not_ fix the issue for FAT's 2 second mtime resolution,
as super_block.s_time_gran isn't prepared to handle different ctime /
mtime / atime resolutions nor resolutions > 1 second.

Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-08-17 11:23:46 -07:00
John Stultz
38bf985b05 timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers
I noticed for non-monotonic timers in timer_list, some of the
output looked a little confusing.

For example:
 #1: <0000000000000000>, posix_timer_fn, S:01, hrtimer_start_range_ns, leap-a-day/2360
 # expires at 1434412800000000000-1434412800000000000 nsecs [in 1434410725062375469 to 1434410725062375469 nsecs]

You'll note the relative time till the expiration "[in xxx to
yyy nsecs]" is incorrect. This is because its printing the delta
between CLOCK_MONOTONIC time to the CLOCK_REALTIME expiration.

This patch fixes this issue by adding the clock offset to the
"now" time which we use to calculate the delta.

Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jiri Bohac <jbohac@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-08-17 11:23:31 -07:00
Oleg Nesterov
bf3eac84c4 percpu-rwsem: kill CONFIG_PERCPU_RWSEM
Remove CONFIG_PERCPU_RWSEM, the next patch adds the unconditional
user of percpu_rw_semaphore.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2015-08-15 13:52:11 +02:00
Oleg Nesterov
9287f6925a percpu-rwsem: introduce percpu_down_read_trylock()
Add percpu_down_read_trylock(), it will have the user soon.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2015-08-15 13:52:10 +02:00
Christoph Hellwig
7d3dcf26a6 devres: add devm_memremap
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-14 16:01:21 -04:00
Linus Torvalds
b25c6cee55 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc fixes: PMU driver corner cases, tooling fixes, and an 'AUX'
  (Intel PT) race related core fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/cqm: Do not access cpu_data() from CPU_UP_PREPARE handler
  perf/x86/intel: Fix memory leak on hot-plug allocation fail
  perf: Fix PERF_EVENT_IOC_PERIOD migration race
  perf: Fix double-free of the AUX buffer
  perf: Fix fasync handling on inherited events
  perf tools: Fix test build error when bindir contains double slash
  perf stat: Fix transaction lenght metrics
  perf: Fix running time accounting
2015-08-14 10:57:16 -07:00
Linus Torvalds
5e5013c6b5 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fix from Ingo Molnar:
 "A single fix for a locking self-test crash"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/pvqspinlock: Fix kernel panic in locking-selftest
2015-08-14 10:45:23 -07:00
Dan Williams
92281dee82 arch: introduce memremap()
Existing users of ioremap_cache() are mapping memory that is known in
advance to not have i/o side effects.  These users are forced to cast
away the __iomem annotation, or otherwise neglect to fix the sparse
errors thrown when dereferencing pointers to this memory.  Provide
memremap() as a non __iomem annotated ioremap_*() in the case when
ioremap is otherwise a pointer to cacheable memory. Empirically,
ioremap_<cacheable-type>() call sites are seeking memory-like semantics
(e.g.  speculative reads, and prefetching permitted).

memremap() is a break from the ioremap implementation pattern of adding
a new memremap_<type>() for each mapping type and having silent
compatibility fall backs.  Instead, the implementation defines flags
that are passed to the central memremap() and if a mapping type is not
supported by an arch memremap returns NULL.

We introduce a memremap prototype as a trivial wrapper of
ioremap_cache() and ioremap_wt().  Later, once all ioremap_cache() and
ioremap_wt() usage has been removed from drivers we teach archs to
implement arch_memremap() with the ability to strictly enforce the
mapping type.

Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-14 13:23:28 -04:00
David Howells
cfc411e7ff Move certificate handling to its own directory
Move certificate handling out of the kernel/ directory and into a certs/
directory to get all the weird stuff in one place and move the generated
signing keys into this directory.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>
2015-08-14 16:06:13 +01:00
David S. Miller
182ad468e7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/cavium/Kconfig

The cavium conflict was overlapping dependency
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 16:23:11 -07:00
Richard Guy Briggs
15ce414b82 fixup: audit: implement audit by executable
The Intel build-bot detected a sparse warning with with a patch I posted a
couple of days ago that was accepted in the audit/next tree:

Subject: [linux-next:master 6689/6751] kernel/audit_watch.c:543:36: sparse: dereference of noderef expression
Date: Friday, August 07, 2015, 06:57:55 PM
From: kbuild test robot <fengguang.wu@intel.com>
tree:   git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   e6455bc5b91f41f842f30465c9193320f0568707
commit: 2e3a8aeb63e5335d4f837d453787c71bcb479796 [6689/6751] Merge remote- tracking branch 'audit/next'
sparse warnings: (new ones prefixed by >>)
>> kernel/audit_watch.c:543:36: sparse: dereference of noderef expression
   kernel/audit_watch.c:544:28: sparse: dereference of noderef expression

34d99af5 Richard Guy Briggs 2015-08-05  541  int audit_exe_compare(struct task_struct *tsk, struct audit_fsnotify_mark *mark)
34d99af5 Richard Guy Briggs 2015-08-05  542  {
34d99af5 Richard Guy Briggs 2015-08-05 @543     unsigned long ino = tsk->mm- >exe_file->f_inode->i_ino;
34d99af5 Richard Guy Briggs 2015-08-05  544     dev_t dev = tsk->mm->exe_file- >f_inode->i_sb->s_dev;

:::::: The code at line 543 was first introduced by commit
:::::: 34d99af52a audit: implement audit by executable

tsk->mm->exe_file requires RCU access.  The warning was reproduceable by adding
"C=1 CF=-D__CHECK_ENDIAN__" to the build command, and verified eliminated with
this patch.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-08-12 22:04:07 -04:00
Wei-Chun Chao
140d8b335a bpf: fix bpf_perf_event_read() loop upper bound
Verifier rejects programs incorrectly.

Fixes: 35578d7984 ("bpf: Implement function bpf_perf_event_read()")
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: Wei-Chun Chao <weichunc@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-12 16:42:50 -07:00
Eric W. Biederman
faf00da544 userns,pidns: Force thread group sharing, not signal handler sharing.
The code that places signals in signal queues computes the uids, gids,
and pids at the time the signals are enqueued.  Which means that tasks
that share signal queues must be in the same pid and user namespaces.

Sharing signal handlers is fine, but bizarre.

So make the code in fork and userns_install clearer by only testing
for what is functionally necessary.

Also update the comment in unshare about unsharing a user namespace to
be a little more explicit and make a little more sense.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-08-12 14:55:28 -05:00
Eric W. Biederman
12c641ab82 unshare: Unsharing a thread does not require unsharing a vm
In the logic in the initial commit of unshare made creating a new
thread group for a process, contingent upon creating a new memory
address space for that process.  That is wrong.  Two separate
processes in different thread groups can share a memory address space
and clone allows creation of such proceses.

This is significant because it was observed that mm_users > 1 does not
mean that a process is multi-threaded, as reading /proc/PID/maps
temporarily increments mm_users, which allows other processes to
(accidentally) interfere with unshare() calls.

Correct the check in check_unshare_flags() to test for
!thread_group_empty() for CLONE_THREAD, CLONE_SIGHAND, and CLONE_VM.
For sighand->count > 1 for CLONE_SIGHAND and CLONE_VM.
For !current_is_single_threaded instead of mm_users > 1 for CLONE_VM.

By using the correct checks in unshare this removes the possibility of
an accidental denial of service attack.

Additionally using the correct checks in unshare ensures that only an
explicit unshare(CLONE_VM) can possibly trigger the slow path of
current_is_single_threaded().  As an explict unshare(CLONE_VM) is
pointless it is not expected there are many applications that make
that call.

Cc: stable@vger.kernel.org
Fixes: b2e0d98705 userns: Implement unshare of the user namespace
Reported-by: Ricky Zhou <rickyz@chromium.org>
Reported-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-08-12 14:54:26 -05:00
David Howells
99db443506 PKCS#7: Appropriately restrict authenticated attributes and content type
A PKCS#7 or CMS message can have per-signature authenticated attributes
that are digested as a lump and signed by the authorising key for that
signature.  If such attributes exist, the content digest isn't itself
signed, but rather it is included in a special authattr which then
contributes to the signature.

Further, we already require the master message content type to be
pkcs7_signedData - but there's also a separate content type for the data
itself within the SignedData object and this must be repeated inside the
authattrs for each signer [RFC2315 9.2, RFC5652 11.1].

We should really validate the authattrs if they exist or forbid them
entirely as appropriate.  To this end:

 (1) Alter the PKCS#7 parser to reject any message that has more than one
     signature where at least one signature has authattrs and at least one
     that does not.

 (2) Validate authattrs if they are present and strongly restrict them.
     Only the following authattrs are permitted and all others are
     rejected:

     (a) contentType.  This is checked to be an OID that matches the
     	 content type in the SignedData object.

     (b) messageDigest.  This must match the crypto digest of the data.

     (c) signingTime.  If present, we check that this is a valid, parseable
     	 UTCTime or GeneralTime and that the date it encodes fits within
     	 the validity window of the matching X.509 cert.

     (d) S/MIME capabilities.  We don't check the contents.

     (e) Authenticode SP Opus Info.  We don't check the contents.

     (f) Authenticode Statement Type.  We don't check the contents.

     The message is rejected if (a) or (b) are missing.  If the message is
     an Authenticode type, the message is rejected if (e) is missing; if
     not Authenticode, the message is rejected if (d) - (f) are present.

     The S/MIME capabilities authattr (d) unfortunately has to be allowed
     to support kernels already signed by the pesign program.  This only
     affects kexec.  sign-file suppresses them (CMS_NOSMIMECAP).

     The message is also rejected if an authattr is given more than once or
     if it contains more than one element in its set of values.

 (3) Add a parameter to pkcs7_verify() to select one of the following
     restrictions and pass in the appropriate option from the callers:

     (*) VERIFYING_MODULE_SIGNATURE

	 This requires that the SignedData content type be pkcs7-data and
	 forbids authattrs.  sign-file sets CMS_NOATTR.  We could be more
	 flexible and permit authattrs optionally, but only permit minimal
	 content.

     (*) VERIFYING_FIRMWARE_SIGNATURE

	 This requires that the SignedData content type be pkcs7-data and
	 requires authattrs.  In future, this will require an attribute
	 holding the target firmware name in addition to the minimal set.

     (*) VERIFYING_UNSPECIFIED_SIGNATURE

	 This requires that the SignedData content type be pkcs7-data but
	 allows either no authattrs or only permits the minimal set.

     (*) VERIFYING_KEXEC_PE_SIGNATURE

	 This only supports the Authenticode SPC_INDIRECT_DATA content type
	 and requires at least an SpcSpOpusInfo authattr in addition to the
	 minimal set.  It also permits an SPC_STATEMENT_TYPE authattr (and
	 an S/MIME capabilities authattr because the pesign program doesn't
	 remove these).

     (*) VERIFYING_KEY_SIGNATURE
     (*) VERIFYING_KEY_SELF_SIGNATURE

	 These are invalid in this context but are included for later use
	 when limiting the use of X.509 certs.

 (4) The pkcs7_test key type is given a module parameter to select between
     the above options for testing purposes.  For example:

	echo 1 >/sys/module/pkcs7_test_key/parameters/usage
	keyctl padd pkcs7_test foo @s </tmp/stuff.pkcs7

     will attempt to check the signature on stuff.pkcs7 as if it contains a
     firmware blob (1 being VERIFYING_FIRMWARE_SIGNATURE).

Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>
2015-08-12 17:01:01 +01:00
David Woodhouse
770f2b9876 modsign: Use extract-cert to process CONFIG_SYSTEM_TRUSTED_KEYS
Fix up the dependencies somewhat too, while we're at it.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-08-12 17:01:01 +01:00
Ingo Molnar
9b9412dc70 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

  - The combination of tree geometry-initialization simplifications
    and OS-jitter-reduction changes to expedited grace periods.
    These two are stacked due to the large number of conflicts
    that would otherwise result.

    [ With one addition, a temporary commit to silence a lockdep false
      positive. Additional changes to the expedited grace-period
      primitives (queued for 4.4) remove the cause of this false
      positive, and therefore include a revert of this temporary commit. ]

  - Documentation updates.

  - Torture-test updates.

  - Miscellaneous fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-12 12:12:12 +02:00