Commit graph

690 commits

Author SHA1 Message Date
Michael Ellerman
f96271cefe Merge branch 'master' into next
Merge master back into next, this allows us to resolve some conflicts in
arch/powerpc/Kconfig, and also re-sort the symbols under config PPC so
that they are in alphabetical order again.
2021-05-08 21:12:55 +10:00
Linus Torvalds
a48b0872e6 Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:
 "This is everything else from -mm for this merge window.

  90 patches.

  Subsystems affected by this patch series: mm (cleanups and slub),
  alpha, procfs, sysctl, misc, core-kernel, bitmap, lib, compat,
  checkpatch, epoll, isofs, nilfs2, hpfs, exit, fork, kexec, gcov,
  panic, delayacct, gdb, resource, selftests, async, initramfs, ipc,
  drivers/char, and spelling"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (90 commits)
  mm: fix typos in comments
  mm: fix typos in comments
  treewide: remove editor modelines and cruft
  ipc/sem.c: spelling fix
  fs: fat: fix spelling typo of values
  kernel/sys.c: fix typo
  kernel/up.c: fix typo
  kernel/user_namespace.c: fix typos
  kernel/umh.c: fix some spelling mistakes
  include/linux/pgtable.h: few spelling fixes
  mm/slab.c: fix spelling mistake "disired" -> "desired"
  scripts/spelling.txt: add "overflw"
  scripts/spelling.txt: Add "diabled" typo
  scripts/spelling.txt: add "overlfow"
  arm: print alloc free paths for address in registers
  mm/vmalloc: remove vwrite()
  mm: remove xlate_dev_kmem_ptr()
  drivers/char: remove /dev/kmem for good
  mm: fix some typos and code style problems
  ipc/sem.c: mundane typo fixes
  ...
2021-05-07 00:34:51 -07:00
Rasmus Villemoes
e7cb072eb9 init/initramfs.c: do unpacking asynchronously
Patch series "background initramfs unpacking, and CONFIG_MODPROBE_PATH", v3.

These two patches are independent, but better-together.

The second is a rather trivial patch that simply allows the developer to
change "/sbin/modprobe" to something else - e.g.  the empty string, so
that all request_module() during early boot return -ENOENT early, without
even spawning a usermode helper, needlessly synchronizing with the
initramfs unpacking.

The first patch delegates decompressing the initramfs to a worker thread,
allowing do_initcalls() in main.c to proceed to the device_ and late_
initcalls without waiting for that decompression (and populating of
rootfs) to finish.  Obviously, some of those later calls may rely on the
initramfs being available, so I've added synchronization points in the
firmware loader and usermodehelper paths - there might be other places
that would need this, but so far no one has been able to think of any
places I have missed.

There's not much to win if most of the functionality needed during boot is
only available as modules.  But systems with a custom-made .config and
initramfs can boot faster, partly due to utilizing more than one cpu
earlier, partly by avoiding known-futile modprobe calls (which would still
trigger synchronization with the initramfs unpacking, thus eliminating
most of the first benefit).

This patch (of 2):

Most of the boot process doesn't actually need anything from the
initramfs, until of course PID1 is to be executed.  So instead of doing
the decompressing and populating of the initramfs synchronously in
populate_rootfs() itself, push that off to a worker thread.

This is primarily motivated by an embedded ppc target, where unpacking
even the rather modest sized initramfs takes 0.6 seconds, which is long
enough that the external watchdog becomes unhappy that it doesn't get
attention soon enough.  By doing the initramfs decompression in a worker
thread, we get to do the device_initcalls and hence start petting the
watchdog much sooner.

Normal desktops might benefit as well.  On my mostly stock Ubuntu kernel,
my initramfs is a 26M xz-compressed blob, decompressing to around 126M.
That takes almost two seconds:

[    0.201454] Trying to unpack rootfs image as initramfs...
[    1.976633] Freeing initrd memory: 29416K

Before this patch, these lines occur consecutively in dmesg.  With this
patch, the timestamps on these two lines is roughly the same as above, but
with 172 lines inbetween - so more than one cpu has been kept busy doing
work that would otherwise only happen after the populate_rootfs()
finished.

Should one of the initcalls done after rootfs_initcall time (i.e., device_
and late_ initcalls) need something from the initramfs (say, a kernel
module or a firmware blob), it will simply wait for the initramfs
unpacking to be done before proceeding, which should in theory make this
completely safe.

But if some driver pokes around in the filesystem directly and not via one
of the official kernel interfaces (i.e.  request_firmware*(),
call_usermodehelper*) that theory may not hold - also, I certainly might
have missed a spot when sprinkling wait_for_initramfs().  So there is an
escape hatch in the form of an initramfs_async= command line parameter.

Link: https://lkml.kernel.org/r/20210313212528.2956377-1-linux@rasmusvillemoes.dk
Link: https://lkml.kernel.org/r/20210313212528.2956377-2-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07 00:26:33 -07:00
Linus Torvalds
939b7cbc00 RISC-V Patches for the 5.13 Merge Window, Part 1
* Support for the memtest= kernel command-line argument.
 * Support for building the kernel with FORTIFY_SOURCE.
 * Support for generic clockevent broadcasts.
 * Support for the buildtar build target.
 * Some build system cleanups to pass more LLVM-friendly arguments.
 * Support for kprobes.
 * A rearranged kernel memory map, the first part of supporting sv48
   systems.
 * Improvements to kexec, along with support for kdump and crash kernels.
 * An alternatives-based errata framework, along with support for
   handling a pair of errata that manifest on some SiFive designs
   (including the HiFive Unmatched).
 * Support for XIP.
 * A device tree for the Microchip PolarFire ICICLE SoC and associated
   dev board.
 
 Along with a bunch of cleanups.  There are already a handful of fixes
 on the list so there will likely be a part 2.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEKzw3R0RoQ7JKlDp6LhMZ81+7GIkFAmCS4lITHHBhbG1lckBk
 YWJiZWx0LmNvbQAKCRAuExnzX7sYieZqEACSihfcOgZ/oyGWN3chca917/yCWimM
 DOu37Zlh81TNPgzzJwbT44IY5sg/lSecwktxs665TChiJjr3JlM4jmz+u64KOTA8
 mTWhqZNr5zT9kFj/m3x0V9yYOVr9g43QRmIlc14d+8JaQDw0N8WeH/yK85/CXDSS
 X5gQK/e9q/yPf/NPyPuPm67jDsFnJERINWaAHI8lhA5fvFyy/xRLmSkuexchysss
 XOGfyxxX590jGLK1vD+5wccX7ZwfwU4jriTaxyah/VBl8QUur/xSPVyspHIdWiMG
 jrNXI1dg6oI861BdjryUpZI0iYJaRe5FRWUx7uTIqHfIyL/MnvYI7USVYOOPb72M
 yZgN903R++5NeUUVTzfXwaigTwfXAPB6USFqZpEfRAf204pgNybmznJWThAVBdYG
 rUixp7GsEMU3aAT2tE/iHR33JQxQfnZq8Tg43/4gB7MoACrzQrYrGcPnj9xssMyV
 F1hnao3dr+5Xjo3MwfkW9JvLPwvDuE3mdrdj+a0XZ45gbTJeuBhYxo3VOsFeijhQ
 gf/VYuoNn5iae9fiMzx5rlmFT9NJDYKDhla+BpAel84/6nRryyfCZCaE5FvDynOO
 CNQynaeJMIMEygPBYR9FVVCwm+EtVsz3NVFKEuo5ilQpgX8ipctxiqy2+moZALLN
 OWlEH6BKEgXqkw==
 =PsA8
 -----END PGP SIGNATURE-----

Merge tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - Support for the memtest= kernel command-line argument.

 - Support for building the kernel with FORTIFY_SOURCE.

 - Support for generic clockevent broadcasts.

 - Support for the buildtar build target.

 - Some build system cleanups to pass more LLVM-friendly arguments.

 - Support for kprobes.

 - A rearranged kernel memory map, the first part of supporting sv48
   systems.

 - Improvements to kexec, along with support for kdump and crash
   kernels.

 - An alternatives-based errata framework, along with support for
   handling a pair of errata that manifest on some SiFive designs
   (including the HiFive Unmatched).

 - Support for XIP.

 - A device tree for the Microchip PolarFire ICICLE SoC and associated
   dev board.

... along with a bunch of cleanups.  There are already a handful of fixes
on the list so there will likely be a part 2.

* tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (45 commits)
  RISC-V: Always define XIP_FIXUP
  riscv: Remove 32b kernel mapping from page table dump
  riscv: Fix 32b kernel build with CONFIG_DEBUG_VIRTUAL=y
  RISC-V: Fix error code returned by riscv_hartid_to_cpuid()
  RISC-V: Enable Microchip PolarFire ICICLE SoC
  RISC-V: Initial DTS for Microchip ICICLE board
  dt-bindings: riscv: microchip: Add YAML documentation for the PolarFire SoC
  RISC-V: Add Microchip PolarFire SoC kconfig option
  RISC-V: enable XIP
  RISC-V: Add crash kernel support
  RISC-V: Add kdump support
  RISC-V: Improve init_resources()
  RISC-V: Add kexec support
  RISC-V: Add EM_RISCV to kexec UAPI header
  riscv: vdso: fix and clean-up Makefile
  riscv/mm: Use BUG_ON instead of if condition followed by BUG.
  riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe
  riscv: Set ARCH_HAS_STRICT_MODULE_RWX if MMU
  riscv: module: Create module allocations without exec permissions
  riscv: bpf: Avoid breaking W^X
  ...
2021-05-06 09:24:18 -07:00
Linus Torvalds
8404c9fbc8 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "The remainder of the main mm/ queue.

  143 patches.

  Subsystems affected by this patch series (all mm): pagecache, hugetlb,
  userfaultfd, vmscan, compaction, migration, cma, ksm, vmstat, mmap,
  kconfig, util, memory-hotplug, zswap, zsmalloc, highmem, cleanups, and
  kfence"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (143 commits)
  kfence: use power-efficient work queue to run delayed work
  kfence: maximize allocation wait timeout duration
  kfence: await for allocation using wait_event
  kfence: zero guard page after out-of-bounds access
  mm/process_vm_access.c: remove duplicate include
  mm/mempool: minor coding style tweaks
  mm/highmem.c: fix coding style issue
  btrfs: use memzero_page() instead of open coded kmap pattern
  iov_iter: lift memzero_page() to highmem.h
  mm/zsmalloc: use BUG_ON instead of if condition followed by BUG.
  mm/zswap.c: switch from strlcpy to strscpy
  arm64/Kconfig: introduce ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
  x86/Kconfig: introduce ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
  mm,memory_hotplug: add kernel boot option to enable memmap_on_memory
  acpi,memhotplug: enable MHP_MEMMAP_ON_MEMORY when supported
  mm,memory_hotplug: allocate memmap from the added memory range
  mm,memory_hotplug: factor out adjusting present pages into adjust_present_page_count()
  mm,memory_hotplug: relax fully spanned sections check
  drivers/base/memory: introduce memory_block_{online,offline}
  mm/memory_hotplug: remove broken locking of zone PCP structures during hot remove
  ...
2021-05-05 13:50:15 -07:00
Linus Torvalds
5d6a1b84e0 gpio updates for v5.13
- new driver for the Realtek Otto GPIO controller
 - ACPI support for gpio-mpc8xxx
 - edge event support for gpio-sch (+ Kconfig fixes)
 - Kconfig improvements in gpio-ich
 - fixes to older issues in gpio-mockup
 - ACPI quirk for ignoring EC wakeups on Dell Venue 10 Pro 5055
 - improve the GPIO aggregator code by using more generic interfaces instead of
   reimplementing them in the driver
 - convert the DT bindings for gpio-74x164 to yaml
 - documentation improvements
 - a slew of other minor fixes and improvements to GPIO drivers
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEFp3rbAvDxGAT0sefEacuoBRx13IFAmCSptQACgkQEacuoBRx
 13KFDQ/+NOkRQuJarKAvGuR5LJ81CbBfH72/m9gJMB9gwNBS7g+esNWrZG/riWVM
 BVs2fxlC52+ppN1rV7iMEaXSyREULrcidgoZ0H7X2vsI9MRkk/fjzpTRwbJbSLPo
 C+IXBAHHfuUC1FQNtQk1cuZXl7PToHd/A14KZIkLOBxLjQddpSo7TTkv23Ub1BA7
 Se13EaDrBJxzfmLR900kAKCFDyM8VRnIt7/euhmlTcXCxOg/lCbGZ4eBpEZasUs5
 UA9PQX0dnnwtMER4b4TQPIdQ345A0l+xqALr8X2leqQ0AqsWQ7kveMwfSRlXI5Hr
 zyuXRiA0e84h6HXIHE59kXqoa4LJVnW59hgjYx0D+fcZ5gNVnaRg/4LsztJmMd/f
 uVAZazE4jd81Cr/kbtpEu5mfGPjOVBeUCeDnKtRovnaSMi24HwqvHqIauI9sM8fN
 locTCYOdLfvxucAJHZ/BWe8yl301/+IlwiHiN+7+/3ljYB+HjAH42rdPwFpP1BWJ
 bpgd90KxLHezeqsv83U9CTTrVK9ZM2yisVunQUo3bVi6Ztxl2Juv16P5Qs0IJW2F
 mly+KNTa4M6NKCdP6luEnazmifFIsnreCzTMfPoa9w+eu/vpIw6lZDFpDAbePV+A
 8XJ99TxV1Bk9kUjvKiEi2qx6uW7f5k8JIwvRvJWhRXkEzufJyUI=
 =5vLN
 -----END PGP SIGNATURE-----

Merge tag 'gpio-updates-for-v5.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux

Pull gpio updates from Bartosz Golaszewski:

 - new driver for the Realtek Otto GPIO controller

 - ACPI support for gpio-mpc8xxx

 - edge event support for gpio-sch (+ Kconfig fixes)

 - Kconfig improvements in gpio-ich

 - fixes to older issues in gpio-mockup

 - ACPI quirk for ignoring EC wakeups on Dell Venue 10 Pro 5055

 - improve the GPIO aggregator code by using more generic interfaces
   instead of reimplementing them in the driver

 - convert the DT bindings for gpio-74x164 to yaml

 - documentation improvements

 - a slew of other minor fixes and improvements to GPIO drivers

* tag 'gpio-updates-for-v5.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (34 commits)
  dt-bindings: gpio: add YAML description for rockchip,gpio-bank
  gpio: mxs: remove useless function
  dt-bindings: gpio: fairchild,74hc595: Convert to json-schema
  gpio: it87: remove unused code
  gpio: 104-dio-48e: Fix coding style issues
  gpio: mpc8xxx: Add ACPI support
  gpio: ich: Switch to be dependent on LPC_ICH
  gpio: sch: Drop MFD_CORE selection
  gpio: sch: depends on LPC_SCH
  gpiolib: acpi: Add quirk to ignore EC wakeups on Dell Venue 10 Pro 5055
  gpio: sch: Hook into ACPI GPE handler to catch GPIO edge events
  gpio: sch: Add edge event support
  gpio: aggregator: Replace custom get_arg() with a generic next_arg()
  lib/cmdline: Export next_arg() for being used in modules
  gpio: omap: Use device_get_match_data() helper
  gpio: Add Realtek Otto GPIO support
  dt-bindings: gpio: Binding for Realtek Otto GPIO
  docs: kernel-parameters: Add gpio_mockup_named_lines
  docs: kernel-parameters: Move gpio-mockup for alphabetic order
  lib: bitmap: provide devm_bitmap_alloc() and devm_bitmap_zalloc()
  ...
2021-05-05 12:39:29 -07:00
Oscar Salvador
e3a9d9fcc3 mm,memory_hotplug: add kernel boot option to enable memmap_on_memory
Self stored memmap leads to a sparse memory situation which is
unsuitable for workloads that requires large contiguous memory chunks,
so make this an opt-in which needs to be explicitly enabled.

To control this, let memory_hotplug have its own memory space, as
suggested by David, so we can add memory_hotplug.memmap_on_memory
parameter.

Link: https://lkml.kernel.org/r/20210421102701.25051-7-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05 11:27:27 -07:00
Alexander Dahl
6984a32034 docs: kernel-parameters: Add gpio_mockup_named_lines
Missing since introduced in the driver.

Fixes: 8a68ea00a6 ("gpio: mockup: implement naming the lines")
Signed-off-by: Alexander Dahl <ada@thorsis.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2021-05-05 16:07:39 +02:00
Alexander Dahl
3eb52226de docs: kernel-parameters: Move gpio-mockup for alphabetic order
All other sections are ordered alphabetically so do the same for
gpio-mockup.

Fixes: 0f98dd1b27 ("gpio/mockup: add virtual gpio device")
Signed-off-by: Alexander Dahl <ada@thorsis.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2021-05-05 16:07:39 +02:00
Nicholas Piggin
8abddd968a powerpc/64s/radix: Enable huge vmalloc mappings
This reduces TLB misses by nearly 30x on a `git diff` workload on a
2-node POWER9 (59,800 -> 2,100) and reduces CPU cycles by 0.54%, due
to vfs hashes being allocated with 2MB pages.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210503091755.613393-1-npiggin@gmail.com
2021-05-04 11:06:45 +10:00
Linus Torvalds
4f9701057a IOMMU Updates for Linux v5.13
Including:
 
 	- Big cleanup of almost unsused parts of the IOMMU API by
 	  Christoph Hellwig. This mostly affects the Freescale PAMU
 	  driver.
 
 	- New IOMMU driver for Unisoc SOCs
 
 	- ARM SMMU Updates from Will:
 
 	  - SMMUv3: Drop vestigial PREFETCH_ADDR support
 	  - SMMUv3: Elide TLB sync logic for empty gather
 	  - SMMUv3: Fix "Service Failure Mode" handling
     	  - SMMUv2: New Qualcomm compatible string
 
 	- Removal of the AMD IOMMU performance counter writeable check
 	  on AMD. It caused long boot delays on some machines and is
 	  only needed to work around an errata on some older (possibly
 	  pre-production) chips. If someone is still hit by this
 	  hardware issue anyway the performance counters will just
 	  return 0.
 
 	- Support for targeted invalidations in the AMD IOMMU driver.
 	  Before that the driver only invalidated a single 4k page or the
 	  whole IO/TLB for an address space. This has been extended now
 	  and is mostly useful for emulated AMD IOMMUs.
 
 	- Several fixes for the Shared Virtual Memory support in the
 	  Intel VT-d driver
 
 	- Mediatek drivers can now be built as modules
 
 	- Re-introduction of the forcedac boot option which got lost
 	  when converting the Intel VT-d driver to the common dma-iommu
 	  implementation.
 
 	- Extension of the IOMMU device registration interface and
 	  support iommu_ops to be const again when drivers are built as
 	  modules.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEr9jSbILcajRFYWYyK/BELZcBGuMFAmCMEIoACgkQK/BELZcB
 GuOu9xAAvg6aR0uHlxvRq6cgNnHN9Ltp5+t3qFYtRRrauY0iOPMO62k0QQli5shX
 CGeczD0e59KAZqI0zNJnQn8hMY5dg7XVkFCC5BrSzuCDCtwJZ0N5Tq3pfUlaV1rw
 BJf41t79Fd+jp7kn53tu+vRAfYZ3+sLOx/6U3c15pqKRZSkyFWbQllOtD3J5LnLu
 1PyPlfiNpMwCajiS7aQbN+fuJ/lKIFeA2MDPOsCBzhbfxiJUqJxZOKAZO3rOjFfK
 feTibqQ+3Zz6MPXt9st1cvPpy8jCosv81OY6Knqvxf/oB5q+fEdi2uNrKISonb/t
 Fw331oOIwg2A+HOpwC9MN1AumOIqiHSWWENAMk9SlP+TMIWKQ8kZreyI6IEB23dV
 +QvP3DVA+CfLwtNY/Zh0IqKh28D+IHlKbpWNU1m+9AUe468mV/MTjfwxr9Yfffhm
 LZ6C0DgFdmtqv8jPuDGUOgo3RNeN8bLnUSEHG9gHibA+RKujl5BWDjKkwILqMQTt
 Ysdsu8TiNtFIULomizqCpgqEbQfW8TLFvASXCM1VMQ/PDURxvchZPxFDJonYXy+K
 z2HGaG3eUE07YrAdRKH69aMVIbmS+sjEhvmi4xZ1Lh7wWcIE2AZVvO8qNb+Ckcp3
 4tLPPDksm/iQngnFf6gdgH3qv4rgbzE4+74GXqeANiQCjY9dSJI=
 =qF2C
 -----END PGP SIGNATURE-----

Merge tag 'iommu-updates-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:

 - Big cleanup of almost unsused parts of the IOMMU API by Christoph
   Hellwig. This mostly affects the Freescale PAMU driver.

 - New IOMMU driver for Unisoc SOCs

 - ARM SMMU Updates from Will:
     - Drop vestigial PREFETCH_ADDR support (SMMUv3)
     - Elide TLB sync logic for empty gather (SMMUv3)
     - Fix "Service Failure Mode" handling (SMMUv3)
     - New Qualcomm compatible string (SMMUv2)

 - Removal of the AMD IOMMU performance counter writeable check on AMD.
   It caused long boot delays on some machines and is only needed to
   work around an errata on some older (possibly pre-production) chips.
   If someone is still hit by this hardware issue anyway the performance
   counters will just return 0.

 - Support for targeted invalidations in the AMD IOMMU driver. Before
   that the driver only invalidated a single 4k page or the whole IO/TLB
   for an address space. This has been extended now and is mostly useful
   for emulated AMD IOMMUs.

 - Several fixes for the Shared Virtual Memory support in the Intel VT-d
   driver

 - Mediatek drivers can now be built as modules

 - Re-introduction of the forcedac boot option which got lost when
   converting the Intel VT-d driver to the common dma-iommu
   implementation.

 - Extension of the IOMMU device registration interface and support
   iommu_ops to be const again when drivers are built as modules.

* tag 'iommu-updates-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (84 commits)
  iommu: Streamline registration interface
  iommu: Statically set module owner
  iommu/mediatek-v1: Add error handle for mtk_iommu_probe
  iommu/mediatek-v1: Avoid build fail when build as module
  iommu/mediatek: Always enable the clk on resume
  iommu/fsl-pamu: Fix uninitialized variable warning
  iommu/vt-d: Force to flush iotlb before creating superpage
  iommu/amd: Put newline after closing bracket in warning
  iommu/vt-d: Fix an error handling path in 'intel_prepare_irq_remapping()'
  iommu/vt-d: Fix build error of pasid_enable_wpe() with !X86
  iommu/amd: Remove performance counter pre-initialization test
  Revert "iommu/amd: Fix performance counter initialization"
  iommu/amd: Remove duplicate check of devid
  iommu/exynos: Remove unneeded local variable initialization
  iommu/amd: Page-specific invalidations for more than one page
  iommu/arm-smmu-v3: Remove the unused fields for PREFETCH_CONFIG command
  iommu/vt-d: Avoid unnecessary cache flush in pasid entry teardown
  iommu/vt-d: Invalidate PASID cache when root/context entry changed
  iommu/vt-d: Remove WO permissions on second-level paging entries
  iommu/vt-d: Report the right page fault address
  ...
2021-05-01 09:33:00 -07:00
Rafael Aquini
82edd9d52e mm/slab_common: provide "slab_merge" option for !IS_ENABLED(CONFIG_SLAB_MERGE_DEFAULT) builds
This is a minor addition to the allocator setup options to provide a
simple way to on demand enable back cache merging for builds that by
default run with CONFIG_SLAB_MERGE_DEFAULT not set.

Link: https://lkml.kernel.org/r/20210319194506.200159-1-aquini@redhat.com
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:36 -07:00
Linus Torvalds
c05a182bf4 for-5.13/libata-2021-04-27
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmCIQeEQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgptU6D/0XSSkUX/SAy7uUHj5MwikMiMZS1ztzRazk
 /pBCrh504tdnQ7Hm4Bq4fcNz9AOqcPafAmvhsdKKfcRAfkpfTsoYJEif07A8wvcL
 /Ajy43dDdCw+XKV0pg06dkYU/YwurtpkRwP+0YcO3UbAqSCyQUv94I1f+xOpExwe
 t/yFbv/fhds7P/FZL7rkVGNPPji+vNDiWsF2rZ7YiOoyiPBdQMElfDRYEuAo7uMN
 lPKIakmNudrNRpNf8SGhSn2Ls1N6glFY+zJMdIj8TKzYm85hsF6CdlDHAdQgx3s4
 5CEmT6biQ6bX+yiMvr3MMzPqfIpOmJzMMGK33hQBrH2k1nvfqg04iFXN48Wf91mk
 0d4Ydq7j4yqjAlOoWqDj4VT2tqm4lv5Q/rToICtUdkuhQyssMvbvoZnUQBdm4LIv
 fLnNZ/DIX2h5FJGguFETWX9y7qUNtU33IGKUuEIf5QTyiaAUjJnUJR1MZudyp0Xz
 rUSk0Nb0kVwN3xNa63xGYok2IPz9SITVmOf9ci5NBPUKBcAZKX4wNiSGQo0Gs9Tb
 vVUhOb0HHB1LtWCZ6pIGoDvJot5bSitF3m9jtNXIbLf4Iqc9AiCO8WtGEn9aY6Xr
 I17IBqUI6to4ur2SUDT1qF4PI+9ZYP2h7z6ExvNX8N3yIL+CPK8cKKHsy2YBNqkP
 +BLgWt0+qA==
 =6EKM
 -----END PGP SIGNATURE-----

Merge tag 'for-5.13/libata-2021-04-27' of git://git.kernel.dk/linux-block

Pull libata updates from Jens Axboe:
 "Mostly cleanups this time, but also a few additions:

   - kernel-doc cleanups and sanitization (Lee)

   - Spelling fix (Bhaskar)

   - Fix ata_qc_from_tag() return value check in dwc_460ex (Dinghao)

   - Fall-through warning fix (Gustavo)

   - IRQ registration fixes (Sergey)

   - Add AHCI support for Tegra186 (Sowjanya)

   - Add xiling phy support for AHCI (Piyush)

   - SXS disable fix for AHCI for Hisilicon Kunpeng920 (Xingui)

   - pata legacy probe mask support (Maciej)"

* tag 'for-5.13/libata-2021-04-27' of git://git.kernel.dk/linux-block: (54 commits)
  libata: Fix fall-through warnings for Clang
  pata_ipx4xx_cf: Fix unsigned comparison with less than zero
  ata: ahci_tegra: call tegra_powergate_power_off only when PM domain is not present
  ata: ahci_tegra: Add AHCI support for Tegra186
  dt-binding: ata: tegra: Add dt-binding documentation for Tegra186
  dt-bindings: ata: tegra: Convert binding documentation to YAML
  pata_legacy: Add `probe_mask' parameter like with ide-generic
  pata_platform: Document `pio_mask' module parameter
  pata_legacy: Properly document module parameters
  ata: ahci: ceva: Updated code by using dev_err_probe()
  ata: ahci: Disable SXS for Hisilicon Kunpeng920
  ata: libahci_platform: fix IRQ check
  sata_mv: add IRQ checks
  ata: pata_acpi: Fix some incorrect function param descriptions
  ata: libata-acpi: Fix function name and provide description for 'prev_gtf'
  ata: sata_mv: Fix misnaming of 'mv_bmdma_stop()'
  ata: pata_cs5530: Fix misspelling of 'cs5530_init_one()'s 'pdev' param
  ata: pata_legacy: Repair a couple kernel-doc problems
  ata: ata_generic: Fix misspelling of 'ata_generic_init_one()'
  ata: pata_opti: Fix spelling issue of 'val' in 'opti_write_reg()'
  ...
2021-04-28 14:50:20 -07:00
Linus Torvalds
16b3d0cf5b Scheduler updates for this cycle are:
- Clean up SCHED_DEBUG: move the decades old mess of sysctl, procfs and debugfs interfaces
    to a unified debugfs interface.
 
  - Signals: Allow caching one sigqueue object per task, to improve performance & latencies.
 
  - Improve newidle_balance() irq-off latencies on systems with a large number of CPU cgroups.
 
  - Improve energy-aware scheduling
 
  - Improve the PELT metrics for certain workloads
 
  - Reintroduce select_idle_smt() to improve load-balancing locality - but without the previous
    regressions
 
  - Add 'scheduler latency debugging': warn after long periods of pending need_resched. This
    is an opt-in feature that requires the enabling of the LATENCY_WARN scheduler feature,
    or the use of the resched_latency_warn_ms=xx boot parameter.
 
  - CPU hotplug fixes for HP-rollback, and for the 'fail' interface. Fix remaining
    balance_push() vs. hotplug holes/races
 
  - PSI fixes, plus allow /proc/pressure/ files to be written by CAP_SYS_RESOURCE tasks as well
 
  - Fix/improve various load-balancing corner cases vs. capacity margins
 
  - Fix sched topology on systems with NUMA diameter of 3 or above
 
  - Fix PF_KTHREAD vs to_kthread() race
 
  - Minor rseq optimizations
 
  - Misc cleanups, optimizations, fixes and smaller updates
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmCJInsRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1i5XxAArh0b+fwXlkVGzTUly7HQjhU7lFbChnmF
 h6ToyNLi6pXoZ14VC/WoRIME+RzK3gmw9cEFaSLVPxbkbekTcyWS78kqmcg1/j2v
 kO/20QhXobiIxVskYfoMmqSavZ5mKhMWBqtFXkCuYfxwGylas0VVdh3AZLJ7N21G
 WEoFh99pVULwWnPHxM2ZQ87Ex9BkGKbsBTswxWpprCfXLqD0N2hHlABpwJP78zRf
 VniWFOcC7lslILCFawb7CqGgAwbgV85nDRS4QCuCKisrkFywvjJrEeu/W+h1NfhF
 d6ves/osNdEAM1DSALoxwEA42An8l8xh8NyJnl8JZV00LW0DM108O5/7pf5Zcryc
 RHV3RxA7skgezBh5uThvo60QzNK+kVMatI4qpQEHxLE52CaDl/fBu1Cgb/VUxnIl
 AEBfyiFbk+skHpuMFKtl30Tx3M+yJKMTzFPd4kYjHYGEDwtAcXcB3dJQW48A79i3
 H3IWcDcXpk5Rjo2UZmaXdt/qlj7mP6U0xdOUq8ZK6JOC4uY9skszVGsfuNN9QQ5u
 2E2YKKVrGFoQydl4C8R6A7axL2VzIJszHFZNipd8E3YOyW7PWRAkr02tOOkBTj8N
 dLMcNM7aPJWqEYiEIjEzGQN20pweJ1dRA29LDuOswKh+7W2bWTQFh6F2Q8Haansc
 RVg5PDzl+Mc=
 =E7mz
 -----END PGP SIGNATURE-----

Merge tag 'sched-core-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:

 - Clean up SCHED_DEBUG: move the decades old mess of sysctl, procfs and
   debugfs interfaces to a unified debugfs interface.

 - Signals: Allow caching one sigqueue object per task, to improve
   performance & latencies.

 - Improve newidle_balance() irq-off latencies on systems with a large
   number of CPU cgroups.

 - Improve energy-aware scheduling

 - Improve the PELT metrics for certain workloads

 - Reintroduce select_idle_smt() to improve load-balancing locality -
   but without the previous regressions

 - Add 'scheduler latency debugging': warn after long periods of pending
   need_resched. This is an opt-in feature that requires the enabling of
   the LATENCY_WARN scheduler feature, or the use of the
   resched_latency_warn_ms=xx boot parameter.

 - CPU hotplug fixes for HP-rollback, and for the 'fail' interface. Fix
   remaining balance_push() vs. hotplug holes/races

 - PSI fixes, plus allow /proc/pressure/ files to be written by
   CAP_SYS_RESOURCE tasks as well

 - Fix/improve various load-balancing corner cases vs. capacity margins

 - Fix sched topology on systems with NUMA diameter of 3 or above

 - Fix PF_KTHREAD vs to_kthread() race

 - Minor rseq optimizations

 - Misc cleanups, optimizations, fixes and smaller updates

* tag 'sched-core-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (61 commits)
  cpumask/hotplug: Fix cpu_dying() state tracking
  kthread: Fix PF_KTHREAD vs to_kthread() race
  sched/debug: Fix cgroup_path[] serialization
  sched,psi: Handle potential task count underflow bugs more gracefully
  sched: Warn on long periods of pending need_resched
  sched/fair: Move update_nohz_stats() to the CONFIG_NO_HZ_COMMON block to simplify the code & fix an unused function warning
  sched/debug: Rename the sched_debug parameter to sched_verbose
  sched,fair: Alternative sched_slice()
  sched: Move /proc/sched_debug to debugfs
  sched,debug: Convert sysctl sched_domains to debugfs
  debugfs: Implement debugfs_create_str()
  sched,preempt: Move preempt_dynamic to debug.c
  sched: Move SCHED_DEBUG sysctl to debugfs
  sched: Don't make LATENCYTOP select SCHED_DEBUG
  sched: Remove sched_schedstats sysctl out from under SCHED_DEBUG
  sched/numa: Allow runtime enabling/disabling of NUMA balance without SCHED_DEBUG
  sched: Use cpu_dying() to fix balance_push vs hotplug-rollback
  cpumask: Introduce DYING mask
  cpumask: Make cpu_{online,possible,present,active}() inline
  rseq: Optimise rseq_get_rseq_cs() and clear_rseq_cs()
  ...
2021-04-28 13:33:57 -07:00
Linus Torvalds
0ff0edb550 Locking changes for this cycle were:
- rtmutex cleanup & spring cleaning pass that removes ~400 lines of code
  - Futex simplifications & cleanups
  - Add debugging to the CSD code, to help track down a tenacious race (or hw problem)
  - Add lockdep_assert_not_held(), to allow code to require a lock to not be held,
    and propagate this into the ath10k driver
  - Misc LKMM documentation updates
  - Misc KCSAN updates: cleanups & documentation updates
  - Misc fixes and cleanups
  - Fix locktorture bugs with ww_mutexes
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmCJDn0RHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1hPrRAAryS4zPnuDsfkVk0smxo7a0lK5ljbH2Xo
 28QUZXOl6upnEV8dzbjwG7eAjt5ZJVI5tKIeG0PV0NUJH2nsyHwESdtULGGYuPf/
 4YUzNwZJa+nI/jeBnVsXCimLVxxnNCRdR7yOVOHm4ukEwa+YTNt1pvlYRmUd4YyH
 Q5cCrpb3THvLka3AAamEbqnHnAdGxHKuuHYVRkODpMQ+zrQvtN8antYsuk8kJsqM
 m+GZg/dVCuLEPah5k+lOACtcq/w7HCmTlxS8t4XLvD52jywFZLcCPvi1rk0+JR+k
 Vd9TngC09GJ4jXuDpr42YKkU9/X6qy2Es39iA/ozCvc1Alrhspx/59XmaVSuWQGo
 XYuEPx38Yuo/6w16haSgp0k4WSay15A4uhCTQ75VF4vli8Bqgg9PaxLyQH1uG8e2
 xk8U90R7bDzLlhKYIx1Vu5Z0t7A1JtB5CJtgpcfg/zQLlzygo75fHzdAiU5fDBDm
 3QQXSU2Oqzt7c5ZypioHWazARk7tL6th38KGN1gZDTm5zwifpaCtHi7sml6hhZ/4
 ATH6zEPzIbXJL2UqumSli6H4ye5ORNjOu32r7YPqLI4IDbzpssfoSwfKYlQG4Tvn
 4H1Ukirzni0gz5+wbleItzf2aeo1rocs4YQTnaT02j8NmUHUz4AzOHGOQFr5Tvh0
 wk/P4MIoSb0=
 =cOOk
 -----END PGP SIGNATURE-----

Merge tag 'locking-core-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:

 - rtmutex cleanup & spring cleaning pass that removes ~400 lines of
   code

 - Futex simplifications & cleanups

 - Add debugging to the CSD code, to help track down a tenacious race
   (or hw problem)

 - Add lockdep_assert_not_held(), to allow code to require a lock to not
   be held, and propagate this into the ath10k driver

 - Misc LKMM documentation updates

 - Misc KCSAN updates: cleanups & documentation updates

 - Misc fixes and cleanups

 - Fix locktorture bugs with ww_mutexes

* tag 'locking-core-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  kcsan: Fix printk format string
  static_call: Relax static_call_update() function argument type
  static_call: Fix unused variable warn w/o MODULE
  locking/rtmutex: Clean up signal handling in __rt_mutex_slowlock()
  locking/rtmutex: Restrict the trylock WARN_ON() to debug
  locking/rtmutex: Fix misleading comment in rt_mutex_postunlock()
  locking/rtmutex: Consolidate the fast/slowpath invocation
  locking/rtmutex: Make text section and inlining consistent
  locking/rtmutex: Move debug functions as inlines into common header
  locking/rtmutex: Decrapify __rt_mutex_init()
  locking/rtmutex: Remove pointless CONFIG_RT_MUTEXES=n stubs
  locking/rtmutex: Inline chainwalk depth check
  locking/rtmutex: Move rt_mutex_debug_task_free() to rtmutex.c
  locking/rtmutex: Remove empty and unused debug stubs
  locking/rtmutex: Consolidate rt_mutex_init()
  locking/rtmutex: Remove output from deadlock detector
  locking/rtmutex: Remove rtmutex deadlock tester leftovers
  locking/rtmutex: Remove rt_mutex_timed_lock()
  MAINTAINERS: Add myself as futex reviewer
  locking/mutex: Remove repeated declaration
  ...
2021-04-28 12:37:53 -07:00
Linus Torvalds
9a45da9270 RCU changes for this cycle were:
- Bitmap support for "N" as alias for last bit
  - kvfree_rcu updates
  - mm_dump_obj() updates.  (One of these is to mm, but was suggested by Andrew Morton.)
  - RCU callback offloading update
  - Polling RCU grace-period interfaces
  - Realtime-related RCU updates
  - Tasks-RCU updates
  - Torture-test updates
  - Torture-test scripting updates
  - Miscellaneous fixes
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmCJCZERHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1hRjw/+Jkb9KvR9odPt/zqN/KPtIlburCUWgsFb
 2zAlWN4uMocPAiXT2Xq58/8gqMkpyn7ZVZtL1tD8fZSvlwEr0U8Z74+/NdoQvYE+
 kMXIYIuhIAGRyAupmzkriqN33iY+BSZPacX3u6ziPj57/0OZzbWVN/DAhbuvyLqG
 J/oL4PHCa7XAqXbf95rd5Zjs680QJ3CbTRh4nA8uHArzJmKZOaaHJ05Pxd1LpULe
 SJ+5p1GQnnwxd1HqmlHMDu/dW+2hE35BGykF8zi78je9OJXualDoM/6JpIYGhMNY
 5qlhU55QYP1jzjuNGVZZUS4L77eS2/W7SpPAaTmMEy/SsVB59G8Kf22oNDpVaEqQ
 m+2ErqwaHvlkMjqnsx+JQbsOP0yCi2NZBoEPFdfk1H23E2deVlSDbxPso4Zb1oUD
 E12769kN+SWDytuLSOAe1PY/KXqmNUKjPZl1GDCGXL7HlCnWyggUDschTsKJa19O
 XXl+yCTGMUH4XAPSqavAKQbBjurqpT6i4zfooSH4TBtOHm1ExgZOUS8gglZ1JuJd
 q+uJdZIgS8BcGkGw/k1bYDWY5TA4Rjv3sAOKQL1PgYBl1t/yLK441mE7LI9gWOwz
 Crz7vlSxD6Jc2cYQeUVW0KPGt5aVd63Gd9HjpXxGkqYQSDRqYMCebHEAGagz+jj7
 Nv/nOnf34Uc=
 =mpNt
 -----END PGP SIGNATURE-----

Merge tag 'core-rcu-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU updates from Ingo Molnar:

 - Support for "N" as alias for last bit in bitmap parsing library (eg
   using syntax like "nohz_full=2-N")

 - kvfree_rcu updates

 - mm_dump_obj() updates. (One of these is to mm, but was suggested by
   Andrew Morton.)

 - RCU callback offloading update

 - Polling RCU grace-period interfaces

 - Realtime-related RCU updates

 - Tasks-RCU updates

 - Torture-test updates

 - Torture-test scripting updates

 - Miscellaneous fixes

* tag 'core-rcu-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits)
  rcutorture: Test start_poll_synchronize_rcu() and poll_state_synchronize_rcu()
  rcu: Provide polling interfaces for Tiny RCU grace periods
  torture: Fix kvm.sh --datestamp regex check
  torture: Consolidate qemu-cmd duration editing into kvm-transform.sh
  torture: Print proper vmlinux path for kvm-again.sh runs
  torture: Make TORTURE_TRUST_MAKE available in kvm-again.sh environment
  torture: Make kvm-transform.sh update jitter commands
  torture: Add --duration argument to kvm-again.sh
  torture: Add kvm-again.sh to rerun a previous torture-test
  torture: Create a "batches" file for build reuse
  torture: De-capitalize TORTURE_SUITE
  torture: Make upper-case-only no-dot no-slash scenario names official
  torture: Rename SRCU-t and SRCU-u to avoid lowercase characters
  torture: Remove no-mpstat error message
  torture: Record kvm-test-1-run.sh and kvm-test-1-run-qemu.sh PIDs
  torture: Record jitter start/stop commands
  torture: Extract kvm-test-1-run-qemu.sh from kvm-test-1-run.sh
  torture: Record TORTURE_KCONFIG_GDB_ARG in qemu-cmd
  torture: Abstract jitter.sh start/stop into scripts
  rcu: Provide polling interfaces for Tree RCU grace periods
  ...
2021-04-28 12:00:13 -07:00
Linus Torvalds
d8f9176b4e ACPI updates for 5.13-rc1
- Update ACPICA code in the kernel to upstream revision 20210331
    including the following changes:
 
    * Add parsing for IVRS IVHD 40h and device entry F0h (Alexander
      Monakov).
 
    * Add new CEDT table for CXL 2.0 and iASL support for it (Ben
      Widawsky, Bob Moore).
 
    * NFIT: add Location Cookie field (Bob Moore).
 
    * HMAT: add new fields/flags (Bob Moore).
 
    * Add new flags in SRAT (Bob Moore).
 
    * PMTT: add new fields/structures (Bob Moore).
 
    * Add CSI2Bus resource template (Bob Moore).
 
    * iASL: Decode subtable type field for VIOT (Bob Moore).
 
    * Fix various typos and spelling mistakes (Colin Ian King).
 
    * Add new predefined objects _BPC, _BPS, and _BPT (Erik Kaneda).
 
    * Add USB4 capabilities UUID (Erik Kaneda).
 
    * Add CXL ACPI device ID and _CBR object (Erik Kaneda).
 
    * MADT: add Multiprocessor Wakeup Structure (Erik Kaneda).
 
    * PCCT: add support for subtable type 5 (Erik Kaneda).
 
    * PPTT: add new version of subtable type 1 (Erik Kaneda).
 
    * Add SDEV secure access components (Erik Kaneda).
 
    * Add support for PHAT table (Erik Kaneda).
 
    * iASL: Add definitions for the VIOT table (Jean-Philippe Brucker).
 
    * acpisrc: Add missing conversion for VIOT support (Jean-Philippe
      Brucker).
 
    * IORT: Updates for revision E.b (Shameer Kolothum).
 
  - Rearrange message printing in ACPI-related code to avoid using the
    ACPICA's internal message printing macros outside ACPICA and do
    some related code cleanups (Rafael Wysocki).
 
  - Modify the device enumeration code to turn off all of the unused
    ACPI power resources at the end (Rafael Wysocki).
 
  - Change the ACPI power resources handling code to turn off unused
    ACPI power resources without checking their status which should
    not be necessary by the spec (Rafael Wysocki).
 
  - Add empty stubs for CPPC-related functions to be used when
    CONFIG_ACPI_CPPC_LIB is not set (Rafael Wysocki).
 
  - Simplify device enumeration code (Rafael Wysocki).
 
  - Change device enumeration code to use match_string() for string
    matching (Andy Shevchenko).
 
  - Modify irqresource_disabled() to retain the resouce flags that
    have been set already (Angela Czubak).
 
  - Add native backlight whitelist entry for GA401/GA502/GA503 (Luke
    Jones).
 
  - Modify the ACPI backlight driver to let the native backlight
    handling take over on hardware-reduced systems (Hans de Goede).
 
  - Introduce acpi_dev_get() and switch over the ACPI core code to
    using it (Andy Shevchenko).
 
  - Use kobj_attribute as callback argument instead of a local struct
    type in the CPPC linrary code (Nathan Chancellor).
 
  - Drop unneeded initializatio of a static variable from the ACPI
    processor driver (Tian Tao).
 
  - Drop unnecessary local variable assignment from the ACPI APEI
    code (Colin Ian King).
 
  - Document for_each_acpi_dev_match() macro (Andy Shevchenko).
 
  - Address assorted coding style issues in multiple places (Xiaofei
    Tan).
 
  - Capitalize TLAs in a few comments (Andy Shevchenko).
 
  - Correct assorted typos in comments (Tom Saeger).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAmCHAL8SHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxZroQAIdFsRUTKmm8st9sdfEtF3QHLS3/EV2x
 1GlkL+3yE/WuEFXNd0mAv0MTcV2sNMKGd5oz74zLkciPC2dNR4168Ni6DhGSoELM
 0ZMOAu9E12Nyq7/1FdWalLQprtR8OuLVwgC2VckK+f//4vzpZ+6PtGMwAwtImSHK
 m3WRPimVbgOVJ1UWZjsfIm7kLBD4o4oCx0pdeEl77q0oQKmMdcByUh2YnjwKzFnP
 9zqV+SCi3HL4w67HO/uMe7x8isNyWONYXVqOvOkgXi7PeoX9v0XiWSCJ0KnAvbI1
 PZokJT8pTrKnFyL3zJS6pU/ZHj7ikFiTc+MfyyPcYRJZ5nBvRjqHKoPOtZ9yfU6n
 jgt/u3REhqwnHy0ikS8HsP+PWnAJF1Re3sNVvIMnX6XxTIndHCXZEoeldfeC23S9
 PmzGA0//iPngiYaOVM5BxIjRi2nRBHlVvzSIACICXDcszA81RHePFIzfjUgW3elp
 v6kAhkrXYajqrDb7NuvY4MTuuBo8w3q2xWJGu5VlDkNOblM0AExRhXmvp1RW0kL7
 +mi5X6xBFEB9M6hEoWKnleaZTXTlFYBreKsMPEEP7N7a5+UZRPedcjX1PflCkOB3
 uL5p/+x3br1fkDyK0P7wFf3VqiBXuwFajEdCmyHnizpD6m0oWC6pv9PUGYUCneJ1
 JGH5X/3Uu33D
 =5fuB
 -----END PGP SIGNATURE-----

Merge tag 'acpi-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "These update the ACPICA code in the kernel to the most recent upstream
  revision including (but not limited to) new material introduced in the
  6.4 version of the spec, update message printing in the ACPI-related
  code, address a few issues and clean up code in a number of places.

  Specifics:

   - Update ACPICA code in the kernel to upstream revision 20210331
     including the following changes:

      * Add parsing for IVRS IVHD 40h and device entry F0h (Alexander
        Monakov).

      * Add new CEDT table for CXL 2.0 and iASL support for it (Ben
        Widawsky, Bob Moore).

      * NFIT: add Location Cookie field (Bob Moore).

      * HMAT: add new fields/flags (Bob Moore).

      * Add new flags in SRAT (Bob Moore).

      * PMTT: add new fields/structures (Bob Moore).

      * Add CSI2Bus resource template (Bob Moore).

      * iASL: Decode subtable type field for VIOT (Bob Moore).

      * Fix various typos and spelling mistakes (Colin Ian King).

      * Add new predefined objects _BPC, _BPS, and _BPT (Erik Kaneda).

      * Add USB4 capabilities UUID (Erik Kaneda).

      * Add CXL ACPI device ID and _CBR object (Erik Kaneda).

      * MADT: add Multiprocessor Wakeup Structure (Erik Kaneda).

      * PCCT: add support for subtable type 5 (Erik Kaneda).

      * PPTT: add new version of subtable type 1 (Erik Kaneda).

      * Add SDEV secure access components (Erik Kaneda).

      * Add support for PHAT table (Erik Kaneda).

      * iASL: Add definitions for the VIOT table (Jean-Philippe
        Brucker).

      * acpisrc: Add missing conversion for VIOT support (Jean-Philippe
        Brucker).

      * IORT: Updates for revision E.b (Shameer Kolothum).

   - Rearrange message printing in ACPI-related code to avoid using the
     ACPICA's internal message printing macros outside ACPICA and do
     some related code cleanups (Rafael Wysocki).

   - Modify the device enumeration code to turn off all of the unused
     ACPI power resources at the end (Rafael Wysocki).

   - Change the ACPI power resources handling code to turn off unused
     ACPI power resources without checking their status which should not
     be necessary by the spec (Rafael Wysocki).

   - Add empty stubs for CPPC-related functions to be used when
     CONFIG_ACPI_CPPC_LIB is not set (Rafael Wysocki).

   - Simplify device enumeration code (Rafael Wysocki).

   - Change device enumeration code to use match_string() for string
     matching (Andy Shevchenko).

   - Modify irqresource_disabled() to retain the resouce flags that have
     been set already (Angela Czubak).

   - Add native backlight whitelist entry for GA401/GA502/GA503 (Luke
     Jones).

   - Modify the ACPI backlight driver to let the native backlight
     handling take over on hardware-reduced systems (Hans de Goede).

   - Introduce acpi_dev_get() and switch over the ACPI core code to
     using it (Andy Shevchenko).

   - Use kobj_attribute as callback argument instead of a local struct
     type in the CPPC linrary code (Nathan Chancellor).

   - Drop unneeded initializatio of a static variable from the ACPI
     processor driver (Tian Tao).

   - Drop unnecessary local variable assignment from the ACPI APEI code
     (Colin Ian King).

   - Document for_each_acpi_dev_match() macro (Andy Shevchenko).

   - Address assorted coding style issues in multiple places (Xiaofei
     Tan).

   - Capitalize TLAs in a few comments (Andy Shevchenko).

   - Correct assorted typos in comments (Tom Saeger)"

* tag 'acpi-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (68 commits)
  ACPI: video: use native backlight for GA401/GA502/GA503
  ACPI: APEI: remove redundant assignment to variable rc
  ACPI: utils: Capitalize abbreviations in the comments
  ACPI: utils: Document for_each_acpi_dev_match() macro
  ACPI: bus: Introduce acpi_dev_get() and reuse it in ACPI code
  ACPI: scan: Utilize match_string() API
  resource: Prevent irqresource_disabled() from erasing flags
  ACPI: CPPC: Replace cppc_attr with kobj_attribute
  ACPI: scan: Call acpi_get_object_info() from acpi_set_pnp_ids()
  ACPI: scan: Drop sta argument from acpi_init_device_object()
  ACPI: scan: Drop sta argument from acpi_add_single_object()
  ACPI: scan: Rearrange checks in acpi_bus_check_add()
  ACPI: scan: Fold acpi_bus_type_and_status() into its caller
  ACPI: video: Check LCD flag on ACPI-reduced-hardware devices
  ACPI: utils: Add acpi_reduced_hardware() helper
  ACPI: dock: fix some coding style issues
  ACPI: sysfs: fix some coding style issues
  ACPI: PM: add a missed blank line after declarations
  ACPI: custom_method: fix a coding style issue
  ACPI: CPPC: fix some coding style issues
  ...
2021-04-26 15:03:23 -07:00
Linus Torvalds
2f9ef0559e It's been a relatively busy cycle in docsland, though more than usually
well contained to Documentation/ itself.  Highlights include:
 
  - The Chinese translators have been busy and show no signs of stopping
    anytime soon.  Italian has also caught up.
 
  - Aditya Srivastava has been working on improvements to the kernel-doc
    script.
 
  - Thorsten continues his work on reporting-issues.rst and related
    documentation around regression reporting.
 
  - Lots of documentation updates, typo fixes, etc. as usual
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmCG5moPHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5YCoUH/1q/O+IvS+JNkxneDxbB6OC799BQpabZHi7/
 HbYfgfX0nKrV3NAwIhigsIj6WHRE+5p2rKiHOuQxL3daJyfZSqQl0/yI0Ag7Of4g
 7y1FKBQrfqS6tJcyNckdtBfxYUQP9yCJY0xfIexkTNiujbmkMKDSJD7lKXd0AaTM
 styCvTbgTPTzadL5bIHj/GxJ9s8DsxO3y9LGdRc+GrNzPFliMYWlJgbR28zjEKBm
 UQzy7JGNBX3qTJwgjvv/myqRDy6MligvGrP+wG0KTnAHXKkvDFl3p46kPwzdk1JE
 +F5sbboUWh20GLYy9t4MZOcq38FUcEPlRPXkxsGNyA8co5ij8+g=
 =7db3
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.13' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It's been a relatively busy cycle in docsland, though more than
  usually well contained to Documentation/ itself. Highlights include:

   - The Chinese translators have been busy and show no signs of
     stopping anytime soon. Italian has also caught up.

   - Aditya Srivastava has been working on improvements to the
     kernel-doc script.

   - Thorsten continues his work on reporting-issues.rst and related
     documentation around regression reporting.

   - Lots of documentation updates, typo fixes, etc. as usual"

* tag 'docs-5.13' of git://git.lwn.net/linux: (139 commits)
  docs/zh_CN: add openrisc translation to zh_CN index
  docs/zh_CN: add openrisc index.rst translation
  docs/zh_CN: add openrisc todo.rst translation
  docs/zh_CN: add openrisc openrisc_port.rst translation
  docs/zh_CN: add core api translation to zh_CN index
  docs/zh_CN: add core-api index.rst translation
  docs/zh_CN: add core-api irq index.rst translation
  docs/zh_CN: add core-api irq irqflags-tracing.rst translation
  docs/zh_CN: add core-api irq irq-domain.rst translation
  docs/zh_CN: add core-api irq irq-affinity.rst translation
  docs/zh_CN: add core-api irq concepts.rst translation
  docs: sphinx-pre-install: don't barf on beta Sphinx releases
  scripts: kernel-doc: improve parsing for kernel-doc comments syntax
  docs/zh_CN: two minor fixes in zh_CN/doc-guide/
  Documentation: dev-tools: Add Testing Overview
  docs/zh_CN: add translations in zh_CN/dev-tools/gcov
  docs: reporting-issues: make people CC the regressions list
  MAINTAINERS: add regressions mailing list
  doc:it_IT: align Italian documentation
  docs/zh_CN: sync reporting-issues.rst
  ...
2021-04-26 13:22:43 -07:00
Linus Torvalds
31a24ae89c arm64 updates for 5.13:
- MTE asynchronous support for KASan. Previously only synchronous
   (slower) mode was supported. Asynchronous is faster but does not allow
   precise identification of the illegal access.
 
 - Run kernel mode SIMD with softirqs disabled. This allows using NEON in
   softirq context for crypto performance improvements. The conditional
   yield support is modified to take softirqs into account and reduce the
   latency.
 
 - Preparatory patches for Apple M1: handle CPUs that only have the VHE
   mode available (host kernel running at EL2), add FIQ support.
 
 - arm64 perf updates: support for HiSilicon PA and SLLC PMU drivers, new
   functions for the HiSilicon HHA and L3C PMU, cleanups.
 
 - Re-introduce support for execute-only user permissions but only when
   the EPAN (Enhanced Privileged Access Never) architecture feature is
   available.
 
 - Disable fine-grained traps at boot and improve the documented boot
   requirements.
 
 - Support CONFIG_KASAN_VMALLOC on arm64 (only with KASAN_GENERIC).
 
 - Add hierarchical eXecute Never permissions for all page tables.
 
 - Add arm64 prctl(PR_PAC_{SET,GET}_ENABLED_KEYS) allowing user programs
   to control which PAC keys are enabled in a particular task.
 
 - arm64 kselftests for BTI and some improvements to the MTE tests.
 
 - Minor improvements to the compat vdso and sigpage.
 
 - Miscellaneous cleanups.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE5RElWfyWxS+3PLO2a9axLQDIXvEFAmB5xkkACgkQa9axLQDI
 XvEBgRAAsr6r8gsBQJP3FDHmbtbVf2ej5QJTCOAQAGHbTt0JH7Pk03pWSBr7h5nF
 vsddRDxxeDgB6xd7jWP7EvDaPxHeB0CdSj5gG8EP/ZdOm8sFAwB1ZIHWikgUgSwW
 nu6R28yXTMSj+EkyFtahMhTMJ1EMF4sCPuIgAo59ST5w/UMMqLCJByOu4ej6RPKZ
 aeSJJWaDLBmbgnTKWxRvCc/MgIx4J/LAHWGkdpGjuMK6SLp38Kdf86XcrklXtzwf
 K30ZYeoKq8zZ+nFOsK9gBVlOlocZcbS1jEbN842jD6imb6vKLQtBWrKk9A6o4v5E
 XulORWcSBhkZb3ItIU9+6SmelUExf0VeVlSp657QXYPgquoIIGvFl6rCwhrdGMGO
 bi6NZKCfJvcFZJoIN1oyhuHejgZSBnzGEcvhvzNdg7ItvOCed7q3uXcGHz/OI6tL
 2TZKddzHSEMVfTo0D+RUsYfasZHI1qAiQ0mWVC31c+YHuRuW/K/jlc3a5TXlSBUa
 Dwu0/zzMLiqx65ISx9i7XNMrngk55uzrS6MnwSByPoz4M4xsElZxt3cbUxQ8YAQz
 jhxTHs1Pwes8i7f4n61ay/nHCFbmVvN/LlsPRpZdwd8JumThLrDolF3tc6aaY0xO
 hOssKtnGY4Xvh/WitfJ5uvDb1vMObJKTXQEoZEJh4hlNQDxdeUE=
 =6NGI
 -----END PGP SIGNATURE-----

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - MTE asynchronous support for KASan. Previously only synchronous
   (slower) mode was supported. Asynchronous is faster but does not
   allow precise identification of the illegal access.

 - Run kernel mode SIMD with softirqs disabled. This allows using NEON
   in softirq context for crypto performance improvements. The
   conditional yield support is modified to take softirqs into account
   and reduce the latency.

 - Preparatory patches for Apple M1: handle CPUs that only have the VHE
   mode available (host kernel running at EL2), add FIQ support.

 - arm64 perf updates: support for HiSilicon PA and SLLC PMU drivers,
   new functions for the HiSilicon HHA and L3C PMU, cleanups.

 - Re-introduce support for execute-only user permissions but only when
   the EPAN (Enhanced Privileged Access Never) architecture feature is
   available.

 - Disable fine-grained traps at boot and improve the documented boot
   requirements.

 - Support CONFIG_KASAN_VMALLOC on arm64 (only with KASAN_GENERIC).

 - Add hierarchical eXecute Never permissions for all page tables.

 - Add arm64 prctl(PR_PAC_{SET,GET}_ENABLED_KEYS) allowing user programs
   to control which PAC keys are enabled in a particular task.

 - arm64 kselftests for BTI and some improvements to the MTE tests.

 - Minor improvements to the compat vdso and sigpage.

 - Miscellaneous cleanups.

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (86 commits)
  arm64/sve: Add compile time checks for SVE hooks in generic functions
  arm64/kernel/probes: Use BUG_ON instead of if condition followed by BUG.
  arm64: pac: Optimize kernel entry/exit key installation code paths
  arm64: Introduce prctl(PR_PAC_{SET,GET}_ENABLED_KEYS)
  arm64: mte: make the per-task SCTLR_EL1 field usable elsewhere
  arm64/sve: Remove redundant system_supports_sve() tests
  arm64: fpsimd: run kernel mode NEON with softirqs disabled
  arm64: assembler: introduce wxN aliases for wN registers
  arm64: assembler: remove conditional NEON yield macros
  kasan, arm64: tests supports for HW_TAGS async mode
  arm64: mte: Report async tag faults before suspend
  arm64: mte: Enable async tag check fault
  arm64: mte: Conditionally compile mte_enable_kernel_*()
  arm64: mte: Enable TCO in functions that can read beyond buffer limits
  kasan: Add report for async mode
  arm64: mte: Drop arch_enable_tagging()
  kasan: Add KASAN mode kernel parameter
  arm64: mte: Add asynchronous mode support
  arm64: Get rid of CONFIG_ARM64_VHE
  arm64: Cope with CPUs stuck in VHE mode
  ...
2021-04-26 10:25:03 -07:00
Linus Torvalds
64f8e73de0 Support for enhanced split lock detection:
Newer CPUs provide a second mechanism to detect operations with lock
   prefix which go accross a cache line boundary. Such operations have to
   take bus lock which causes a system wide performance degradation when
   these operations happen frequently.
 
   The new mechanism is not using the #AC exception. It triggers #DB and is
   restricted to operations in user space. Kernel side split lock access can
   only be detected by the #AC based variant. Contrary to the #AC based
   mechanism the #DB based variant triggers _after_ the instruction was
   executed. The mechanism is CPUID enumerated and contrary to the #AC
   version which is based on the magic TEST_CTRL_MSR and model/family based
   enumeration on the way to become architectural.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmCGkr8THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYodUKD/9tUXhInR7+1ykEHpMvdmSp48vqY3nc
 sKmT22pPl+OchnJ62mw3T8gKpBYVleJmcCaY2qVx7hfaVcWApLGJvX4tmfXmv422
 XDSJ6b8Os6wfgx5FR//I17z8ZtXnnuKkPrTMoRsQUw2qLq31y6fdQv+GW/cc1Kpw
 mengjmPE+HnpaKbtuQfPdc4a+UvLjvzBMAlDZPTBPKYrP4FFqYVnUVwyTg5aLVDY
 gHz4V8+b502RS/zPfTAtE3J848od+NmcUPdFlcG9DVA+hR0Rl0thvruCTFiD2vVh
 i9DJ7INof5FoJDEzh0dGsD7x+MB6OY8GZyHdUMeGgIRPtWkqrG52feQQIn2YYlaL
 fB3DlpNv7NIJ/0JMlALvh8S0tEoOcYdHqH+M/3K/zbzecg/FAo+lVo8WciGLPqWs
 ykUG5/f/OnlTvgB8po1ebJu0h0jHnoK9heWWXk9zWIRVDPXHFOWKW3kSbTTb3icR
 9hfjP/SNejpmt9Ju1OTwsgnV7NALIdVX+G5jyIEsjFl31Co1RZNYhHLFvi11FWlQ
 /ssvFK9O5ZkliocGCAN9+yuOnM26VqWSCE4fis6/2aSgD2Y4Gpvb//cP96SrcNAH
 u8eXNvGLlniJP3F3JImWIfIPQTrpvQhcU4eZ6NtviXqj/utQXX6c9PZ1PLYpcvUh
 9AWF8rwhT8X4oA==
 =lmi8
 -----END PGP SIGNATURE-----

Merge tag 'x86-splitlock-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 bus lock detection updates from Thomas Gleixner:
 "Support for enhanced split lock detection:

  Newer CPUs provide a second mechanism to detect operations with lock
  prefix which go accross a cache line boundary. Such operations have to
  take bus lock which causes a system wide performance degradation when
  these operations happen frequently.

  The new mechanism is not using the #AC exception. It triggers #DB and
  is restricted to operations in user space. Kernel side split lock
  access can only be detected by the #AC based variant.

  Contrary to the #AC based mechanism the #DB based variant triggers
  _after_ the instruction was executed. The mechanism is CPUID
  enumerated and contrary to the #AC version which is based on the magic
  TEST_CTRL_MSR and model/family based enumeration on the way to become
  architectural"

* tag 'x86-splitlock-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Documentation/admin-guide: Change doc for split_lock_detect parameter
  x86/traps: Handle #DB for bus lock
  x86/cpufeatures: Enumerate #DB for bus lock detection
2021-04-26 10:09:38 -07:00
Linus Torvalds
eea2647e74 Entry code update:
Provide support for randomized stack offsets per syscall to make
  stack-based attacks harder which rely on the deterministic stack layout.
 
  The feature is based on the original idea of PaX's RANDSTACK feature, but
  uses a significantly different implementation.
 
  The offset does not affect the pt_regs location on the task stack as this
  was agreed on to be of dubious value. The offset is applied before the
  actual syscall is invoked.
 
  The offset is stored per cpu and the randomization happens at the end of
  the syscall which is less predictable than on syscall entry.
 
  The mechanism to apply the offset is via alloca(), i.e. abusing the
  dispised VLAs. This comes with the drawback that stack-clash-protection
  has to be disabled for the affected compilation units and there is also
  a negative interaction with stack-protector.
 
  Those downsides are traded with the advantage that this approach does not
  require any intrusive changes to the low level assembly entry code, does
  not affect the unwinder and the correct stack alignment is handled
  automatically by the compiler.
 
  The feature is guarded with a static branch which avoids the overhead when
  disabled.
 
  Currently this is supported for X86 and ARM64.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmCGjz8THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoWsvD/4tGnPAurd6lbzxWzRjW7jOOVyzkODM
 UXtIxxICaj7o6MNcloaGe1QtJ8+QOCw3yPQfLG/SoWHse5+oUKQRL9dmWVeJyRSt
 JZ1pirkKqWrB+OmPbJKUiO3/TsZ2Z/vO41JVgVTL5/HWhOECSDzZsJkuvF/H+qYD
 ReDzd7FUNd76pwVOsXq/cxXclRa81/wMNZRVwmyAwFYE2XoPtQyTERTLrfj6aQKF
 P0txr9fEjYlPPwYOk1kjBAoJfDltNm48BBL7CGZtRlsqpNpdsJ1MkeGffhodb6F0
 pJYQMlQJHXABZb5GF+v93+iASDpRFn0EvPmLkCxQUfZYLOkRsnuEF2S/fsYX/WPo
 uin/wQKwLVdeQq9d9BwlZUKEgsQuV7Q0GVN+JnEQerwD6cWTxv4a1RIUH+K/4Wo5
 nTeJVRKcs6m7UkGQRm8JbqnUP0vCV+PSiWWB8J9CmjYeCPbkGjt6mBIsmPaDZ9VL
 4i+UX5DJayoREF/rspOBcJftUmExize49p9860UI9N6fd7DsDt7Dq9Ai+ADtZa4C
 9BPbF4NWzJq8IWLqBi+PpKBAT3JMX9qQi7s9sbrRxpxtew9Keu5qggKZJYumX71V
 qgUMk+xB86HZOrtF6F3oY0zxYv3haPvDydsDgqojtqNGk4PdAdgDYJQwMlb8QSly
 SwIWPHIfvP4R9w==
 =GMlJ
 -----END PGP SIGNATURE-----

Merge tag 'x86-entry-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull entry code update from Thomas Gleixner:
 "Provide support for randomized stack offsets per syscall to make
  stack-based attacks harder which rely on the deterministic stack
  layout.

  The feature is based on the original idea of PaX's RANDSTACK feature,
  but uses a significantly different implementation.

  The offset does not affect the pt_regs location on the task stack as
  this was agreed on to be of dubious value. The offset is applied
  before the actual syscall is invoked.

  The offset is stored per cpu and the randomization happens at the end
  of the syscall which is less predictable than on syscall entry.

  The mechanism to apply the offset is via alloca(), i.e. abusing the
  dispised VLAs. This comes with the drawback that
  stack-clash-protection has to be disabled for the affected compilation
  units and there is also a negative interaction with stack-protector.

  Those downsides are traded with the advantage that this approach does
  not require any intrusive changes to the low level assembly entry
  code, does not affect the unwinder and the correct stack alignment is
  handled automatically by the compiler.

  The feature is guarded with a static branch which avoids the overhead
  when disabled.

  Currently this is supported for X86 and ARM64"

* tag 'x86-entry-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  arm64: entry: Enable random_kstack_offset support
  lkdtm: Add REPORT_STACK for checking stack offsets
  x86/entry: Enable random_kstack_offset support
  stack: Optionally randomize kernel stack offset each syscall
  init_on_alloc: Optimize static branches
  jump_label: Provide CONFIG-driven build state defaults
2021-04-26 10:02:09 -07:00
Peter Zijlstra
9406415f46 sched/debug: Rename the sched_debug parameter to sched_verbose
CONFIG_SCHED_DEBUG is the build-time Kconfig knob, the boot param
sched_debug and the /debug/sched/debug_enabled knobs control the
sched_debug_enabled variable, but what they really do is make
SCHED_DEBUG more verbose, so rename the lot.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-04-17 13:22:44 +02:00
Sumit Garg
5d0682be31 KEYS: trusted: Add generic trusted keys framework
Current trusted keys framework is tightly coupled to use TPM device as
an underlying implementation which makes it difficult for implementations
like Trusted Execution Environment (TEE) etc. to provide trusted keys
support in case platform doesn't posses a TPM device.

Add a generic trusted keys framework where underlying implementations
can be easily plugged in. Create struct trusted_key_ops to achieve this,
which contains necessary functions of a backend.

Also, define a module parameter in order to select a particular trust
source in case a platform support multiple trust sources. In case its
not specified then implementation itetrates through trust sources list
starting with TPM and assign the first trust source as a backend which
has initiazed successfully during iteration.

Note that current implementation only supports a single trust source at
runtime which is either selectable at compile time or during boot via
aforementioned module parameter.

Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2021-04-14 16:30:30 +03:00
Marc Zyngier
2d726d0db6 arm64: Get rid of CONFIG_ARM64_VHE
CONFIG_ARM64_VHE was introduced with ARMv8.1 (some 7 years ago),
and has been enabled by default for almost all that time.

Given that newer systems that are VHE capable are finally becoming
available, and that some systems are even incapable of not running VHE,
drop the configuration altogether.

Anyone willing to stick to non-VHE on VHE hardware for obscure
reasons should use the 'kvm-arm.mode=nvhe' command-line option.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210408131010.1109027-4-maz@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-04-08 18:45:16 +01:00
Kees Cook
39218ff4c6 stack: Optionally randomize kernel stack offset each syscall
This provides the ability for architectures to enable kernel stack base
address offset randomization. This feature is controlled by the boot
param "randomize_kstack_offset=on/off", with its default value set by
CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT.

This feature is based on the original idea from the last public release
of PaX's RANDKSTACK feature: https://pax.grsecurity.net/docs/randkstack.txt
All the credit for the original idea goes to the PaX team. Note that
the design and implementation of this upstream randomize_kstack_offset
feature differs greatly from the RANDKSTACK feature (see below).

Reasoning for the feature:

This feature aims to make harder the various stack-based attacks that
rely on deterministic stack structure. We have had many such attacks in
past (just to name few):

https://jon.oberheide.org/files/infiltrate12-thestackisback.pdf
https://jon.oberheide.org/files/stackjacking-infiltrate11.pdf
https://googleprojectzero.blogspot.com/2016/06/exploiting-recursion-in-linux-kernel_20.html

As Linux kernel stack protections have been constantly improving
(vmap-based stack allocation with guard pages, removal of thread_info,
STACKLEAK), attackers have had to find new ways for their exploits
to work. They have done so, continuing to rely on the kernel's stack
determinism, in situations where VMAP_STACK and THREAD_INFO_IN_TASK_STRUCT
were not relevant. For example, the following recent attacks would have
been hampered if the stack offset was non-deterministic between syscalls:

https://repositorio-aberto.up.pt/bitstream/10216/125357/2/374717.pdf
(page 70: targeting the pt_regs copy with linear stack overflow)

https://a13xp0p0v.github.io/2020/02/15/CVE-2019-18683.html
(leaked stack address from one syscall as a target during next syscall)

The main idea is that since the stack offset is randomized on each system
call, it is harder for an attack to reliably land in any particular place
on the thread stack, even with address exposures, as the stack base will
change on the next syscall. Also, since randomization is performed after
placing pt_regs, the ptrace-based approach[1] to discover the randomized
offset during a long-running syscall should not be possible.

Design description:

During most of the kernel's execution, it runs on the "thread stack",
which is pretty deterministic in its structure: it is fixed in size,
and on every entry from userspace to kernel on a syscall the thread
stack starts construction from an address fetched from the per-cpu
cpu_current_top_of_stack variable. The first element to be pushed to the
thread stack is the pt_regs struct that stores all required CPU registers
and syscall parameters. Finally the specific syscall function is called,
with the stack being used as the kernel executes the resulting request.

The goal of randomize_kstack_offset feature is to add a random offset
after the pt_regs has been pushed to the stack and before the rest of the
thread stack is used during the syscall processing, and to change it every
time a process issues a syscall. The source of randomness is currently
architecture-defined (but x86 is using the low byte of rdtsc()). Future
improvements for different entropy sources is possible, but out of scope
for this patch. Further more, to add more unpredictability, new offsets
are chosen at the end of syscalls (the timing of which should be less
easy to measure from userspace than at syscall entry time), and stored
in a per-CPU variable, so that the life of the value does not stay
explicitly tied to a single task.

As suggested by Andy Lutomirski, the offset is added using alloca()
and an empty asm() statement with an output constraint, since it avoids
changes to assembly syscall entry code, to the unwinder, and provides
correct stack alignment as defined by the compiler.

In order to make this available by default with zero performance impact
for those that don't want it, it is boot-time selectable with static
branches. This way, if the overhead is not wanted, it can just be
left turned off with no performance impact.

The generated assembly for x86_64 with GCC looks like this:

...
ffffffff81003977: 65 8b 05 02 ea 00 7f  mov %gs:0x7f00ea02(%rip),%eax
					    # 12380 <kstack_offset>
ffffffff8100397e: 25 ff 03 00 00        and $0x3ff,%eax
ffffffff81003983: 48 83 c0 0f           add $0xf,%rax
ffffffff81003987: 25 f8 07 00 00        and $0x7f8,%eax
ffffffff8100398c: 48 29 c4              sub %rax,%rsp
ffffffff8100398f: 48 8d 44 24 0f        lea 0xf(%rsp),%rax
ffffffff81003994: 48 83 e0 f0           and $0xfffffffffffffff0,%rax
...

As a result of the above stack alignment, this patch introduces about
5 bits of randomness after pt_regs is spilled to the thread stack on
x86_64, and 6 bits on x86_32 (since its has 1 fewer bit required for
stack alignment). The amount of entropy could be adjusted based on how
much of the stack space we wish to trade for security.

My measure of syscall performance overhead (on x86_64):

lmbench: /usr/lib/lmbench/bin/x86_64-linux-gnu/lat_syscall -N 10000 null
    randomize_kstack_offset=y	Simple syscall: 0.7082 microseconds
    randomize_kstack_offset=n	Simple syscall: 0.7016 microseconds

So, roughly 0.9% overhead growth for a no-op syscall, which is very
manageable. And for people that don't want this, it's off by default.

There are two gotchas with using the alloca() trick. First,
compilers that have Stack Clash protection (-fstack-clash-protection)
enabled by default (e.g. Ubuntu[3]) add pagesize stack probes to
any dynamic stack allocations. While the randomization offset is
always less than a page, the resulting assembly would still contain
(unreachable!) probing routines, bloating the resulting assembly. To
avoid this, -fno-stack-clash-protection is unconditionally added to
the kernel Makefile since this is the only dynamic stack allocation in
the kernel (now that VLAs have been removed) and it is provably safe
from Stack Clash style attacks.

The second gotcha with alloca() is a negative interaction with
-fstack-protector*, in that it sees the alloca() as an array allocation,
which triggers the unconditional addition of the stack canary function
pre/post-amble which slows down syscalls regardless of the static
branch. In order to avoid adding this unneeded check and its associated
performance impact, architectures need to carefully remove uses of
-fstack-protector-strong (or -fstack-protector) in the compilation units
that use the add_random_kstack() macro and to audit the resulting stack
mitigation coverage (to make sure no desired coverage disappears). No
change is visible for this on x86 because the stack protector is already
unconditionally disabled for the compilation unit, but the change is
required on arm64. There is, unfortunately, no attribute that can be
used to disable stack protector for specific functions.

Comparison to PaX RANDKSTACK feature:

The RANDKSTACK feature randomizes the location of the stack start
(cpu_current_top_of_stack), i.e. including the location of pt_regs
structure itself on the stack. Initially this patch followed the same
approach, but during the recent discussions[2], it has been determined
to be of a little value since, if ptrace functionality is available for
an attacker, they can use PTRACE_PEEKUSR/PTRACE_POKEUSR to read/write
different offsets in the pt_regs struct, observe the cache behavior of
the pt_regs accesses, and figure out the random stack offset. Another
difference is that the random offset is stored in a per-cpu variable,
rather than having it be per-thread. As a result, these implementations
differ a fair bit in their implementation details and results, though
obviously the intent is similar.

[1] https://lore.kernel.org/kernel-hardening/2236FBA76BA1254E88B949DDB74E612BA4BC57C1@IRSMSX102.ger.corp.intel.com/
[2] https://lore.kernel.org/kernel-hardening/20190329081358.30497-1-elena.reshetova@intel.com/
[3] https://lists.ubuntu.com/archives/ubuntu-devel/2019-June/040741.html

Co-developed-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210401232347.2791257-4-keescook@chromium.org
2021-04-08 14:05:19 +02:00
Maciej W. Rozycki
7d33004d24 pata_legacy: Add `probe_mask' parameter like with ide-generic
Carry the `probe_mask' parameter over from ide-generic to pata_legacy so
that there is a way to prevent random poking at ISA port I/O locations
in attempt to discover adapter option cards with libata like with the
old IDE driver.  By default all enabled locations are tried, however it
may interfere with a different kind of hardware responding there.

For example with a plain (E)ISA system the driver tries all the six
possible locations:

scsi host0: pata_legacy
ata1: PATA max PIO4 cmd 0x1f0 ctl 0x3f6 irq 14
ata1.00: ATA-4: ST310211A, 3.54, max UDMA/100
ata1.00: 19541088 sectors, multi 16: LBA
ata1.00: configured for PIO
scsi 0:0:0:0: Direct-Access     ATA      ST310211A        3.54 PQ: 0 ANSI: 5
scsi 0:0:0:0: Attached scsi generic sg0 type 0
sd 0:0:0:0: [sda] 19541088 512-byte logical blocks: (10.0 GB/9.32 GiB)
sd 0:0:0:0: [sda] Write Protect is off
sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00
sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
 sda: sda1 sda2 sda3
sd 0:0:0:0: [sda] Attached SCSI disk
scsi host1: pata_legacy
ata2: PATA max PIO4 cmd 0x170 ctl 0x376 irq 15
scsi host1: pata_legacy
ata3: PATA max PIO4 cmd 0x1e8 ctl 0x3ee irq 11
scsi host1: pata_legacy
ata4: PATA max PIO4 cmd 0x168 ctl 0x36e irq 10
scsi host1: pata_legacy
ata5: PATA max PIO4 cmd 0x1e0 ctl 0x3e6 irq 8
scsi host1: pata_legacy
ata6: PATA max PIO4 cmd 0x160 ctl 0x366 irq 12

however giving the kernel "pata_legacy.probe_mask=21" makes it try every
other location only:

scsi host0: pata_legacy
ata1: PATA max PIO4 cmd 0x1f0 ctl 0x3f6 irq 14
ata1.00: ATA-4: ST310211A, 3.54, max UDMA/100
ata1.00: 19541088 sectors, multi 16: LBA
ata1.00: configured for PIO
scsi 0:0:0:0: Direct-Access     ATA      ST310211A        3.54 PQ: 0 ANSI: 5
scsi 0:0:0:0: Attached scsi generic sg0 type 0
sd 0:0:0:0: [sda] 19541088 512-byte logical blocks: (10.0 GB/9.32 GiB)
sd 0:0:0:0: [sda] Write Protect is off
sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00
sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
 sda: sda1 sda2 sda3
sd 0:0:0:0: [sda] Attached SCSI disk
scsi host1: pata_legacy
ata2: PATA max PIO4 cmd 0x1e8 ctl 0x3ee irq 11
scsi host1: pata_legacy
ata3: PATA max PIO4 cmd 0x1e0 ctl 0x3e6 irq 8

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2103211800110.21463@angie.orcam.me.uk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-06 09:27:30 -06:00
Maciej W. Rozycki
6ddcec9547 pata_platform: Document `pio_mask' module parameter
Add MODULE_PARM_DESC documentation and a kernel-parameters.txt entry.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2103212023190.21463@angie.orcam.me.uk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-06 09:27:30 -06:00
Maciej W. Rozycki
426e2c6a2c pata_legacy: Properly document module parameters
Most pata_legacy module parameters lack MODULE_PARM_DESC documentation
and none is described in kernel-parameters.txt.  Also several comments
are inaccurate or wrong.

Add the missing documentation pieces then and reorder parameters into a
consistent block.  Remove inaccuracies as follows:

- `all' affects primary and secondary port ranges only rather than all,

- `probe_all' affects tertiary and further port ranges rather than all,

- `ht6560b' is for HT 6560B rather than HT 6560A.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2103211909560.21463@angie.orcam.me.uk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-06 09:27:30 -06:00
Fenghua Yu
ebca17707e Documentation/admin-guide: Change doc for split_lock_detect parameter
Since #DB for bus lock detect changes the split_lock_detect parameter,
update the documentation for the changes.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210322135325.682257-4-fenghua.yu@intel.com
2021-03-28 22:52:16 +02:00
Paul E. McKenney
ab6ad3dbdd Merge branches 'bitmaprange.2021.03.08a', 'fixes.2021.03.15a', 'kvfree_rcu.2021.03.08a', 'mmdumpobj.2021.03.08a', 'nocb.2021.03.15a', 'poll.2021.03.24a', 'rt.2021.03.08a', 'tasks.2021.03.08a', 'torture.2021.03.08a' and 'torturescript.2021.03.22a' into HEAD
bitmaprange.2021.03.08a:  Allow 3-N for bitmap ranges.
fixes.2021.03.15a:  Miscellaneous fixes.
kvfree_rcu.2021.03.08a:  kvfree_rcu() updates.
mmdumpobj.2021.03.08a:  mem_dump_obj() updates.
nocb.2021.03.15a:  RCU NOCB CPU updates, including limited deoffloading.
poll.2021.03.24a:  Polling grace-period interfaces for RCU.
rt.2021.03.08a:  Realtime-related RCU changes.
tasks.2021.03.08a:  Tasks-RCU updates.
torture.2021.03.08a:  Torture-test updates.
torturescript.2021.03.22a:  Torture-test scripting updates.
2021-03-24 17:20:18 -07:00
Robin Murphy
3542dcb15c iommu/dma: Resurrect the "forcedac" option
In converting intel-iommu over to the common IOMMU DMA ops, it quietly
lost the functionality of its "forcedac" option. Since this is a handy
thing both for testing and for performance optimisation on certain
platforms, reimplement it under the common IOMMU parameter namespace.

For the sake of fixing the inadvertent breakage of the Intel-specific
parameter, remove the dmar_forcedac remnants and hook it up as an alias
while documenting the transition to the new common parameter.

Fixes: c588072bba ("iommu/vt-d: Convert intel iommu driver to the iommu ops")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/7eece8e0ea7bfbe2cd0e30789e0d46df573af9b0.1614961776.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-03-18 10:55:23 +01:00
Kefeng Wang
f6e5aedf47
riscv: Add support for memtest
The riscv [rv32_]defconfig enabled CONFIG_MEMTEST,
but memtest feature is not supported in RISCV.

Add early_memtest() to support for memtest.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-09 18:09:46 -08:00
Barry Song
00b072c011 Documentation/admin-guide: kernel-parameters: correct the architectures for numa_balancing
X86 isn't the only architecture supporting NUMA_BALANCING. ARM64, PPC,
S390 and RISCV also support it:

arch$ git grep NUMA_BALANCING
arm64/Kconfig:  select ARCH_SUPPORTS_NUMA_BALANCING
arm64/configs/defconfig:CONFIG_NUMA_BALANCING=y
arm64/include/asm/pgtable.h:#ifdef CONFIG_NUMA_BALANCING
powerpc/configs/powernv_defconfig:CONFIG_NUMA_BALANCING=y
powerpc/configs/ppc64_defconfig:CONFIG_NUMA_BALANCING=y
powerpc/configs/pseries_defconfig:CONFIG_NUMA_BALANCING=y
powerpc/include/asm/book3s/64/pgtable.h:#ifdef CONFIG_NUMA_BALANCING
powerpc/include/asm/book3s/64/pgtable.h:#ifdef CONFIG_NUMA_BALANCING
powerpc/include/asm/book3s/64/pgtable.h:#endif /* CONFIG_NUMA_BALANCING */
powerpc/include/asm/book3s/64/pgtable.h:#ifdef CONFIG_NUMA_BALANCING
powerpc/include/asm/book3s/64/pgtable.h:#endif /* CONFIG_NUMA_BALANCING */
powerpc/include/asm/nohash/pgtable.h:#ifdef CONFIG_NUMA_BALANCING
powerpc/include/asm/nohash/pgtable.h:#endif /* CONFIG_NUMA_BALANCING */
powerpc/platforms/Kconfig.cputype:      select ARCH_SUPPORTS_NUMA_BALANCING
riscv/Kconfig:  select ARCH_SUPPORTS_NUMA_BALANCING
riscv/include/asm/pgtable.h:#ifdef CONFIG_NUMA_BALANCING
s390/Kconfig:   select ARCH_SUPPORTS_NUMA_BALANCING
s390/configs/debug_defconfig:CONFIG_NUMA_BALANCING=y
s390/configs/defconfig:CONFIG_NUMA_BALANCING=y
s390/include/asm/pgtable.h:#ifdef CONFIG_NUMA_BALANCING
x86/Kconfig:    select ARCH_SUPPORTS_NUMA_BALANCING     if X86_64
x86/include/asm/pgtable.h:#ifdef CONFIG_NUMA_BALANCING
x86/include/asm/pgtable.h:#endif /* CONFIG_NUMA_BALANCING */

On the other hand, setup_numabalancing() is implemented in mm/mempolicy.c
which doesn't depend on architectures.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210302084159.33688-1-song.bao.hua@hisilicon.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-08 17:19:05 -07:00
Uladzislau Rezki (Sony)
686fe1bf6b rcuscale: Add kfree_rcu() single-argument scale test
The single-argument variant of kfree_rcu() is currently not
tested by any member of the rcutoture test suite.  This
commit therefore adds rcuscale code to test it.  This
testing is controlled by two new boolean module parameters,
kfree_rcu_test_single and kfree_rcu_test_double.  If one
is set and the other not, only the corresponding variant
is tested, otherwise both are tested, with the variant to
be tested determined randomly on each invocation.

Both of these module parameters are initialized to false,
so setting either to true will test only that variant.

Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-08 14:18:07 -08:00
Paul Gortmaker
3e70df91f9 rcu: deprecate "all" option to rcu_nocbs=
With the core bitmap support now accepting "N" as a placeholder for
the end of the bitmap, "all" can be represented as "0-N" and has the
advantage of not being specific to RCU (or any other subsystem).

So deprecate the use of "all" by removing documentation references
to it.  The support itself needs to remain for now, since we don't
know how many people out there are using it currently, but since it
is in an __init area anyway, it isn't worth losing sleep over.

Cc: Yury Norov <yury.norov@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Acked-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-08 14:16:58 -08:00
Rafael J. Wysocki
866d6cdf35 ACPI: PCI: Drop ACPI_PCI_COMPONENT that is not used any more
After dropping all of the code using ACPI_PCI_COMPONENT drop the
definition of it too and update the documentation to remove all
ACPI_PCI_COMPONENT references from it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
2021-03-08 16:51:09 +01:00
Juergen Gross
a5aabace5f locking/csd_lock: Add more data to CSD lock debugging
In order to help identifying problems with IPI handling and remote
function execution add some more data to IPI debugging code.

There have been multiple reports of CPUs looping long times (many
seconds) in smp_call_function_many() waiting for another CPU executing
a function like tlb flushing. Most of these reports have been for
cases where the kernel was running as a guest on top of KVM or Xen
(there are rumours of that happening under VMWare, too, and even on
bare metal).

Finding the root cause hasn't been successful yet, even after more than
2 years of chasing this bug by different developers.

Commit:

  35feb60474 ("kernel/smp: Provide CSD lock timeout diagnostics")

tried to address this by adding some debug code and by issuing another
IPI when a hang was detected. This helped mitigating the problem
(the repeated IPI unlocks the hang), but the root cause is still unknown.

Current available data suggests that either an IPI wasn't sent when it
should have been, or that the IPI didn't result in the target CPU
executing the queued function (due to the IPI not reaching the CPU,
the IPI handler not being called, or the handler not seeing the queued
request).

Try to add more diagnostic data by introducing a global atomic counter
which is being incremented when doing critical operations (before and
after queueing a new request, when sending an IPI, and when dequeueing
a request). The counter value is stored in percpu variables which can
be printed out when a hang is detected.

The data of the last event (consisting of sequence counter, source
CPU, target CPU, and event type) is stored in a global variable. When
a new event is to be traced, the data of the last event is stored in
the event related percpu location and the global data is updated with
the new event's data. This allows to track two events in one data
location: one by the value of the event data (the event before the
current one), and one by the location itself (the current event).

A typical printout with a detected hang will look like this:

csd: Detected non-responsive CSD lock (#1) on CPU#1, waiting 5000000003 ns for CPU#06 scf_handler_1+0x0/0x50(0xffffa2a881bb1410).
	csd: CSD lock (#1) handling prior scf_handler_1+0x0/0x50(0xffffa2a8813823c0) request.
        csd: cnt(00008cc): ffff->0000 dequeue (src cpu 0 == empty)
        csd: cnt(00008cd): ffff->0006 idle
        csd: cnt(0003668): 0001->0006 queue
        csd: cnt(0003669): 0001->0006 ipi
        csd: cnt(0003e0f): 0007->000a queue
        csd: cnt(0003e10): 0001->ffff ping
        csd: cnt(0003e71): 0003->0000 ping
        csd: cnt(0003e72): ffff->0006 gotipi
        csd: cnt(0003e73): ffff->0006 handle
        csd: cnt(0003e74): ffff->0006 dequeue (src cpu 0 == empty)
        csd: cnt(0003e7f): 0004->0006 ping
        csd: cnt(0003e80): 0001->ffff pinged
        csd: cnt(0003eb2): 0005->0001 noipi
        csd: cnt(0003eb3): 0001->0006 queue
        csd: cnt(0003eb4): 0001->0006 noipi
        csd: cnt now: 0003f00

The idea is to print only relevant entries. Those are all events which
are associated with the hang (so sender side events for the source CPU
of the hanging request, and receiver side events for the target CPU),
and the related events just before those (for adding data needed to
identify a possible race). Printing all available data would be
possible, but this would add large amounts of data printed on larger
configurations.

Signed-off-by: Juergen Gross <jgross@suse.com>
[ Minor readability edits. Breaks col80 but is far more readable. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20210301101336.7797-4-jgross@suse.com
2021-03-06 12:49:48 +01:00
Juergen Gross
8d0968cc6b locking/csd_lock: Add boot parameter for controlling CSD lock debugging
Currently CSD lock debugging can be switched on and off via a kernel
config option only. Unfortunately there is at least one problem with
CSD lock handling pending for about 2 years now, which has been seen
in different environments (mostly when running virtualized under KVM
or Xen, at least once on bare metal). Multiple attempts to catch this
issue have finally led to introduction of CSD lock debug code, but
this code is not in use in most distros as it has some impact on
performance.

In order to be able to ship kernels with CONFIG_CSD_LOCK_WAIT_DEBUG
enabled even for production use, add a boot parameter for switching
the debug functionality on. This will reduce any performance impact
of the debug coding to a bare minimum when not being used.

Signed-off-by: Juergen Gross <jgross@suse.com>
[ Minor edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210301101336.7797-2-jgross@suse.com
2021-03-06 12:49:48 +01:00
Vijayanand Jitta
e1fdc40334 lib: stackdepot: add support to disable stack depot
Add a kernel parameter stack_depot_disable to disable stack depot.  So
that stack hash table doesn't consume any memory when stack depot is
disabled.

The use case is CONFIG_PAGE_OWNER without page_owner=on.  Without this
patch, stackdepot will consume the memory for the hashtable.  By default,
it's 8M which is never trivial.

With this option, in CONFIG_PAGE_OWNER configured system, page_owner=off,
stack_depot_disable in kernel command line, we could save the wasted
memory for the hashtable.

[akpm@linux-foundation.org: fix CONFIG_STACKDEPOT=n build]

Link: https://lkml.kernel.org/r/1611749198-24316-2-git-send-email-vjitta@codeaurora.org
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Yogesh Lal <ylal@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:04 -08:00
Linus Torvalds
4c48faba5b Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "A few small subsystems and some of MM.

  172 patches.

  Subsystems affected by this patch series: hexagon, scripts, ntfs,
  ocfs2, vfs, and mm (slab-generic, slab, slub, debug, pagecache, swap,
  memcg, pagemap, mprotect, mremap, page-reporting, vmalloc, kasan,
  pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
  mempolicy, oom-kill, hugetlbfs, and migration)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (172 commits)
  mm/migrate: remove unneeded semicolons
  hugetlbfs: remove unneeded return value of hugetlb_vmtruncate()
  hugetlbfs: fix some comment typos
  hugetlbfs: correct some obsolete comments about inode i_mutex
  hugetlbfs: make hugepage size conversion more readable
  hugetlbfs: remove meaningless variable avoid_reserve
  hugetlbfs: correct obsolete function name in hugetlbfs_read_iter()
  hugetlbfs: use helper macro default_hstate in init_hugetlbfs_fs
  hugetlbfs: remove useless BUG_ON(!inode) in hugetlbfs_setattr()
  hugetlbfs: remove special hugetlbfs_set_page_dirty()
  mm/hugetlb: change hugetlb_reserve_pages() to type bool
  mm, oom: fix a comment in dump_task()
  mm/mempolicy: use helper range_in_vma() in queue_pages_test_walk()
  numa balancing: migrate on fault among multiple bound nodes
  mm, compaction: make fast_isolate_freepages() stay within zone
  mm/compaction: fix misbehaviors of fast_find_migrateblock()
  mm/compaction: correct deferral logic for proactive compaction
  mm/compaction: remove duplicated VM_BUG_ON_PAGE !PageLocked
  mm/compaction: remove rcu_read_lock during page compaction
  z3fold: simplify the zhdr initialization code in init_z3fold_page()
  ...
2021-02-24 16:20:38 -08:00
Vlastimil Babka
fe2cce15d6 mm, slub: remove slub_memcg_sysfs boot param and CONFIG_SLUB_MEMCG_SYSFS_ON
The boot param and config determine the value of memcg_sysfs_enabled,
which is unused since commit 10befea91b ("mm: memcg/slab: use a single
set of kmem_caches for all allocations") as there are no per-memcg kmem
caches anymore.

Link: https://lkml.kernel.org/r/20210127124745.7928-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24 13:38:27 -08:00
Linus Torvalds
c4fbde84fe Simple Firmware Interface (SFI) support removal for v5.12-rc1
Drop support for depercated platforms using SFI, drop the entire
 support for SFI that has been long deprecated too and make some
 janitorial changes on top of that (Andy Shevchenko).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAmA2ZukSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxKcAP/RAkbRVFndhQIZYTCu74O64v86FjTBcS
 3vvcKevVkBJiPJL1l10Yo3UMEYAbJIRZY00jkUjX7pq4eurELu6LwdMtJlHwh0p5
 ZP5QeSdq1xN+9UGwBGXlnka2ypmD8fjbQyxHKErYgvmOl4ltFm40PyUC9GCVFLnW
 /1o83t/dcmTtaOGPYWTW3HuCsbYqANG/x8PYAFeAk5dBxoSaNV69gAEuCYr1JC5N
 Nie4x2m2I5v9egJFhy6rmRrpHPBvocCho+FipJFagSKWHPCI2rBSKESVOj23zWt2
 eIWhK5T/ZR3OqQb9tZN6uAPJmBAerc3l7ZHZ1oFBP68MjUJJJhduQ+hNxljOyLLw
 CVx0UhuancIWZdyJon5f7E9S9STZLIZ/3usx3K+7AZK+PSmH8d/UEIeXfkC0FcAr
 eO3gwalB9KuhhXbVvihW79RkfkV5pTaMvVS7l1BffN4WE1dB9PKtJ8/MKFbGaTUF
 4Rev6BdAEDqJrw6OIARvNcI6TAEhbKe5yIghzhQWn+fZ7oEm6f6fvFObBzD0KvQP
 4RwYJhXU0gtK5yo/Ib1sUqjVQn8Jgqb7Xq46WZsP07Yc6O2Ws/86qCpX1GSCv5FU
 1CZEJLGLGTbjDYOyMaUDfO/tI5kXG11e0Ss7Q+snWH4Iyhg0aNEYChKjOAFIxIxg
 JJYOH8O5p2IP
 =jlPz
 -----END PGP SIGNATURE-----

Merge tag 'sfi-removal-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull Simple Firmware Interface (SFI) support removal from Rafael Wysocki:
 "Drop support for depercated platforms using SFI, drop the entire
  support for SFI that has been long deprecated too and make some
  janitorial changes on top of that (Andy Shevchenko)"

* tag 'sfi-removal-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  x86/platform/intel-mid: Update Copyright year and drop file names
  x86/platform/intel-mid: Remove unused header inclusion in intel-mid.h
  x86/platform/intel-mid: Drop unused __intel_mid_cpu_chip and Co.
  x86/platform/intel-mid: Get rid of intel_scu_ipc_legacy.h
  x86/PCI: Describe @reg for type1_access_ok()
  x86/PCI: Get rid of custom x86 model comparison
  sfi: Remove framework for deprecated firmware
  cpufreq: sfi-cpufreq: Remove driver for deprecated firmware
  media: atomisp: Remove unused header
  mfd: intel_msic: Remove driver for deprecated platform
  x86/apb_timer: Remove driver for deprecated platform
  x86/platform/intel-mid: Remove unused leftovers (vRTC)
  x86/platform/intel-mid: Remove unused leftovers (msic)
  x86/platform/intel-mid: Remove unused leftovers (msic_thermal)
  x86/platform/intel-mid: Remove unused leftovers (msic_power_btn)
  x86/platform/intel-mid: Remove unused leftovers (msic_gpio)
  x86/platform/intel-mid: Remove unused leftovers (msic_battery)
  x86/platform/intel-mid: Remove unused leftovers (msic_ocd)
  x86/platform/intel-mid: Remove unused leftovers (msic_audio)
  platform/x86: intel_scu_wdt: Drop mistakenly added const
2021-02-24 10:35:29 -08:00
Linus Torvalds
7ac1161c27 Driver core / debugfs update for 5.12-rc1
Here is the "big" driver core and debugfs update for 5.12-rc1
 
 This set of driver core patches caused a bunch of problems in linux-next
 for the past few weeks, when Saravana tried to set fw_devlink=on as the
 default functionality.  This caused a number of systems to stop booting,
 and lots of bugs were fixed in this area for almost all of the reported
 systems, but this option is not ready to be turned on just yet for the
 default operation based on this testing, so I've reverted that change at
 the very end so we don't have to worry about regressions in 5.12.  We
 will try to turn this on for 5.13 if testing goes better over the next
 few months.
 
 Other than the fixes caused by the fw_devlink testing in here, there's
 not much more:
 	- debugfs fixes for invalid input into debugfs_lookup()
 	- kerneldoc cleanups
 	- warn message if platform drivers return an error on their
 	  remove callback (a futile effort, but good to catch).
 
 All of these have been in linux-next for a while now, and the
 regressions have gone away with the revert of the fw_devlink change.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCYDZhzA8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ylS2wCfU28FxDWNwcWhPFVfRT8Mb3OxZ50An1sR4lNR
 t5Ie4aztMUjVJhI9bq6g
 =3NSB
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core / debugfs update from Greg KH:
 "Here is the "big" driver core and debugfs update for 5.12-rc1

  This set of driver core patches caused a bunch of problems in
  linux-next for the past few weeks, when Saravana tried to set
  fw_devlink=on as the default functionality. This caused a number of
  systems to stop booting, and lots of bugs were fixed in this area for
  almost all of the reported systems, but this option is not ready to be
  turned on just yet for the default operation based on this testing, so
  I've reverted that change at the very end so we don't have to worry
  about regressions in 5.12

  We will try to turn this on for 5.13 if testing goes better over the
  next few months.

  Other than the fixes caused by the fw_devlink testing in here, there's
  not much more:

   - debugfs fixes for invalid input into debugfs_lookup()

   - kerneldoc cleanups

   - warn message if platform drivers return an error on their remove
     callback (a futile effort, but good to catch).

  All of these have been in linux-next for a while now, and the
  regressions have gone away with the revert of the fw_devlink change"

* tag 'driver-core-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (35 commits)
  Revert "driver core: Set fw_devlink=on by default"
  of: property: fw_devlink: Ignore interrupts property for some configs
  debugfs: do not attempt to create a new file before the filesystem is initalized
  debugfs: be more robust at handling improper input in debugfs_lookup()
  driver core: auxiliary bus: Fix calling stage for auxiliary bus init
  of: irq: Fix the return value for of_irq_parse_one() stub
  of: irq: make a stub for of_irq_parse_one()
  clk: Mark fwnodes when their clock provider is added/removed
  PM: domains: Mark fwnodes when their powerdomain is added/removed
  irqdomain: Mark fwnodes when their irqdomain is added/removed
  driver core: fw_devlink: Handle suppliers that don't use driver core
  of: property: Add fw_devlink support for optional properties
  driver core: Add fw_devlink.strict kernel param
  of: property: Don't add links to absent suppliers
  driver core: fw_devlink: Detect supplier devices that will never be added
  driver core: platform: Emit a warning if a remove callback returned non-zero
  of: property: Fix fw_devlink handling of interrupts/interrupts-extended
  gpiolib: Don't probe gpio_device if it's not the primary device
  device.h: Remove bogus "the" in kerneldoc
  gpiolib: Bind gpio_device to a driver to enable fw_devlink=on by default
  ...
2021-02-24 10:13:55 -08:00
Linus Torvalds
143983e585 dmaengine updates for v5.12-rc1
New drivers/devices
  - Intel LGM SoC DMA driver
  - Actions Semi S500 DMA controller
  - Renesas r8a779a0 dma controller
  - Ingenic JZ4760(B) dma controller
  - Intel KeemBay AxiDMA controller
 
 Removed
  - Coh901318 dma driver
  - Zte zx dma driver
  - Sirfsoc dma driver
 
 Updates:
  - mmp_pdma, mmp_tdma gained module support
  - imx-sdma become modern and dropped platform data support
  - dw-axi driver gained slave and cyclic dma support
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE+vs47OPLdNbVcHzyfBQHDyUjg0cFAmA0gIEACgkQfBQHDyUj
 g0fLyw//bfIBqmyvN01QNmYV0qrud0nZGRAGHSEwZ1Nrw2CvK37+XphYzVYy/PGk
 Cg6ca+QXGJdIfqmQV/rnIEwrNx/GeNUAulVT5hxdHQw/HDPoZexU5S+Lyetr4g7l
 FaE2C5se4RBp07eGhcOWkneHE/fhC9fX23VdNGNM6Nzb1F0j4MTmzcJAlsdCq2Q+
 1UlJ2O4w/t/mdqgec4J+JGTsfb+BXxs0nWnuwVSy1SEkac3Gj0kqHlIHsQqLCiST
 /D2rs1I0Chscu+ChrPNaVXDEobQipxIEdkzO6623t8C5KqfSf5i8rLvZvRP5YKf1
 U5ZAi3p0c/t5VgXvA6WD79pN6ZLPsEMFDxyKQAazGPgrEP4gmI4dteETiJyr6Ag6
 j6WqiDJwkmdVyuTiFDJsN3pTOqvT+TeHlLbnygAiuyMeNaF9skc7kxtq0XtXQigT
 vLcwtGavFnmF7TZGjEVv4JTMdMFPfczE8y+fhM7ET/uF36gTrPHaoD3KIwgimwIt
 Cmfpe+Ij8R3tBwV80454hp4+Gb+cR83OUgwy+EcBCw9P0/Pf4t0NyTgim+wN02Kt
 X7tkkgxGkvziIkfbXQa4zdVqAbT6+WcRUjEDZY3/Lp7EFyVyM8APEVSAie9b/TWN
 UgQo3TDuB6SU7XQ3Ahj6Swra0+UoVztHtwOmgIqiVz5on6780lg=
 =0AE9
 -----END PGP SIGNATURE-----

Merge tag 'dmaengine-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine

Pull dmaengine updates from Vinod Koul:
 "We have couple of drivers removed a new driver and bunch of new device
  support and few updates to drivers for this round.

  New drivers/devices:
   - Intel LGM SoC DMA driver
   - Actions Semi S500 DMA controller
   - Renesas r8a779a0 dma controller
   - Ingenic JZ4760(B) dma controller
   - Intel KeemBay AxiDMA controller

  Removed:
   - Coh901318 dma driver
   - Zte zx dma driver
   - Sirfsoc dma driver

  Updates:
   - mmp_pdma, mmp_tdma gained module support
   - imx-sdma become modern and dropped platform data support
   - dw-axi driver gained slave and cyclic dma support"

* tag 'dmaengine-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (58 commits)
  dmaengine: dw-axi-dmac: remove redundant null check on desc
  dmaengine: xilinx_dma: Alloc tx descriptors GFP_NOWAIT
  dmaengine: dw-axi-dmac: Virtually split the linked-list
  dmaengine: dw-axi-dmac: Set constraint to the Max segment size
  dmaengine: dw-axi-dmac: Add Intel KeemBay AxiDMA BYTE and HALFWORD registers
  dmaengine: dw-axi-dmac: Add Intel KeemBay AxiDMA handshake
  dmaengine: dw-axi-dmac: Add Intel KeemBay AxiDMA support
  dmaengine: drivers: Kconfig: add HAS_IOMEM dependency to DW_AXI_DMAC
  dmaengine: dw-axi-dmac: Add Intel KeemBay DMA register fields
  dt-binding: dma: dw-axi-dmac: Add support for Intel KeemBay AxiDMA
  dmaengine: dw-axi-dmac: Support burst residue granularity
  dmaengine: dw-axi-dmac: Support of_dma_controller_register()
  dmaegine: dw-axi-dmac: Support device_prep_dma_cyclic()
  dmaengine: dw-axi-dmac: Support device_prep_slave_sg
  dmaengine: dw-axi-dmac: Add device_config operation
  dmaengine: dw-axi-dmac: Add device_synchronize() callback
  dmaengine: dw-axi-dmac: move dma_pool_create() to alloc_chan_resources()
  dmaengine: dw-axi-dmac: simplify descriptor management
  dt-bindings: dma: Add YAML schemas for dw-axi-dmac
  dmaengine: ti: k3-psil: optimize struct psil_endpoint_config for size
  ...
2021-02-23 15:05:10 -08:00
Linus Torvalds
b2bec7d8a4 printk changes for 5.12
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEESH4wyp42V4tXvYsjUqAMR0iAlPIFAmAzp8UACgkQUqAMR0iA
 lPKHvxAAhB7XsfLaQkpDrqqTswssl85ouQwxwPc6EO52CJx/O5gdZ576vG6Xa1e+
 0+79LwutQupTdYpM19mszkopdNr2NDov9ClQB0yGiiwsFlWLe1FvITe3SO4QzxsX
 Wl78uYPCXWmnj3FnKLgfz6+mIGD4wvNrrFAztPiZ1GNHqjo48RFD6RybIXa3hR/j
 Fx4C7R5eKnbIBophKT4bt1FE0ci9HonDhVYYGyHC6aYNlpTHGYENig32fbkZh6nI
 qdyBvtAyfRbihyOTJrsKlXXb3mb27oWVY6e0+tTabBC3tWBmtorpBbFG8HcBEoS2
 a5UDLtv2m6adFyFTc1ulF9+IPvLqUx8cweGkM1e/XNYZmZAvoUVKyFeiUNBcKhpm
 5ZXYcAZPfWzf2MtFo4mMeLubkPAxk01FWTplt54az2T0B+DnuRieDYarcjrts9ib
 4qvyljqEZ5/uvtoi2O+MRje7roOgx3Hb6JgvhIpObY5XV7MMeeMoFQpGKRUxosE7
 J8f1fhr37OeD2BRwcqMuf7NNBUISFZnzynaTOghXpBSRAKoa+GPzKhOLalKg1nhI
 7LAFGq39CeV9DU59AuWLOmqXCRv7bmjs05vEJtCVv3p+vlvBCiKMhGz6RuGj3OaV
 L2pHXBpUxfSIDtl8wVqA+004J8G4n7i77cWpymiNm+yS5WjoVO0=
 =CZnB
 -----END PGP SIGNATURE-----

Merge tag 'printk-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk updates from Petr Mladek:

 - New "no_hash_pointers" kernel parameter causes that %p shows raw
   pointer values instead of hashed ones. It is intended only for
   debugging purposes. Misuse is prevented by a fat warning message that
   is inspired by trace_printk().

 - Prevent a possible deadlock when flushing printk_safe buffers during
   panic().

 - Fix performance regression caused by the lockless printk ringbuffer.
   It was visible with huge log buffer and long messages.

 - Documentation fix-up.

* tag 'printk-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  lib/vsprintf: no_hash_pointers prints all addresses as unhashed
  kselftest: add support for skipped tests
  lib: use KSTM_MODULE_GLOBALS macro in kselftest drivers
  printk: avoid prb_first_valid_seq() where possible
  printk: fix deadlock when kernel panic
  printk: rectify kernel-doc for prb_rec_init_wr()
2021-02-22 11:04:36 -08:00
Linus Torvalds
0e63a5c6ba It has been a relatively quiet cycle in docsland.
- As promised, the minimum Sphinx version to build the docs is now 1.7,
    and we have dropped support for Python 2 entirely.  That allowed the
    removal of a bunch of compatibility code.
 
  - A set of treewide warning fixups from Mauro that I applied after it
    became clear nobody else was going to deal with them.
 
  - The automarkup mechanism can now create cross-references from relative
    paths to RST files.
 
  - More translations, typo fixes, and warning fixes.
 
 No conflicts with any other tree as far as I know.
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmAq4EUPHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5YTIAH/1I5MlVQwuvNKjwCAEdmltQgHv6SmXSpDkrp
 SGuviWVXxqz8dTyo7C2R12qE/7nP8zGAmclNdX78ynl5qWaj05lQsjBgMYSoQO/F
 +akyLQSL8/8SQrtDPPBcboPuIz9DzkX51kkQthvCf0puJi0ScKVHO9Sk9SKUgDoK
 cnCE9VwpGL7YX/ee2wt91UYREijgJ9P7eQ6rqKvUZ5Itu9ikfu9vQU41GR9tOXDK
 MQK+k38pWdl8wRgTgA0pkVhMf1G732bxTTicvFHXcyqmCkh7++m2+ysT8O+SBBMX
 e5BbP0yysSqThjwFHOW5PWM1AWD5iVz+pnwJwEaJ4K76tJJOw9M=
 =bcDk
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.12' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It has been a relatively quiet cycle in docsland.

   - As promised, the minimum Sphinx version to build the docs is now
     1.7, and we have dropped support for Python 2 entirely. That
     allowed the removal of a bunch of compatibility code.

   - A set of treewide warning fixups from Mauro that I applied after it
     became clear nobody else was going to deal with them.

   - The automarkup mechanism can now create cross-references from
     relative paths to RST files.

   - More translations, typo fixes, and warning fixes"

* tag 'docs-5.12' of git://git.lwn.net/linux: (75 commits)
  docs: kernel-hacking: be more civil
  docs: Remove the Microsoft rhetoric
  Documentation/admin-guide: kernel-parameters: Update nohlt section
  doc/admin-guide: fix spelling mistake: "perfomance" -> "performance"
  docs: Document cross-referencing using relative path
  docs: Enable usage of relative paths to docs on automarkup
  docs: thermal: fix spelling mistakes
  Documentation: admin-guide: Update kvm/xen config option
  docs: Make syscalls' helpers naming consistent
  coding-style.rst: Avoid comma statements
  Documentation: /proc/loadavg: add 3 more field descriptions
  Documentation/submitting-patches: Add blurb about backtraces in commit messages
  Docs: drop Python 2 support
  Move our minimum Sphinx version to 1.7
  Documentation: input: define ABS_PRESSURE/ABS_MT_PRESSURE resolution as grams
  scripts/kernel-doc: add internal hyperlink to DOC: sections
  Update Documentation/admin-guide/sysctl/fs.rst
  docs: Update DTB format references
  docs: zh_CN: add iio index.rst translation
  docs/zh_CN: add iio ep93xx_adc.rst translation
  ...
2021-02-22 10:57:46 -08:00
Linus Torvalds
d643a99089 integrity-v5.12
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCAAyFiEEjSMCCC7+cjo3nszSa3kkZrA+cVoFAmArRwIUHHpvaGFyQGxp
 bnV4LmlibS5jb20ACgkQa3kkZrA+cVo6JxAAkZHDhv6Zv7FfVsFjE7yDJwRFBu4o
 jnAowPxa/xl6MlR2ICTFLHjOimEcpvzySO2IM85WCxjRYaNevITOxEZE+qfE/Byo
 K1MuZOSXXBa2+AgO1Tku+ZNrQvzTsphgtvhlSD9ReN7P84C/rxG5YDomME+8/6rR
 QH7Ly/izyc3VNKq7nprT8F2boJ0UxpcwNHZiH2McQD3UvUaZOecwpcpvth5pbgad
 Ej2r72Q+IR0voqM/T1dc4TjW5Wcw/m27vhGQoOfQ5f+as5r9r1cPSWj0wRJTkATo
 F/SiKuyWUwOGkRO8I9aaXXzTBgcJw/7MmZe8yNDg5QJrUzD8F5cdjlHZdsnz5BJq
 tLo4kUsR4xMePEppJ4a10ZUDQa737j97C20xTwOHf6mKGIqmoooGAsjW9xUyYqHU
 rYuLP4qB7ua4j8Uz9zVJazjgQWPQ+8Ad9MkjQLLhr00Azpz4mVweWVGjCJQC0pky
 Jr2H4xj3JLAoygqMWfJxr9aVBpfy4Wmo0U29ryZuxZUr178qSXoL3QstGWXRa2MN
 TwzpgHi1saItQ6iXAO0HB6Tsw0h8INyjrm7c3ANbmBwMsYMYeKcTG87+Z0LkK82w
 C5SW2uQT9aLBXx9lZx8z0RpxygO1cW+KjlZxRYSfQa/ev/aF2kBz0ruGQgvqai4K
 ceh/cwrYjrCbFVc=
 =mojv
 -----END PGP SIGNATURE-----

Merge tag 'integrity-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull IMA updates from Mimi Zohar:
 "New is IMA support for measuring kernel critical data, as per usual
  based on policy. The first example measures the in memory SELinux
  policy. The second example measures the kernel version.

  In addition are four bug fixes to address memory leaks and a missing
  'static' function declaration"

* tag 'integrity-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  integrity: Make function integrity_add_key() static
  ima: Free IMA measurement buffer after kexec syscall
  ima: Free IMA measurement buffer on error
  IMA: Measure kernel version in early boot
  selinux: include a consumer of the new IMA critical data hook
  IMA: define a builtin critical data measurement policy
  IMA: extend critical data hook to limit the measurement based on a label
  IMA: limit critical data measurement based on a label
  IMA: add policy rule to measure critical data
  IMA: define a hook to measure kernel integrity critical data
  IMA: add support to measure buffer data hash
  IMA: generalize keyring specific measurement constructs
  evm: Fix memleak in init_desc
2021-02-21 17:08:06 -08:00
Linus Torvalds
99ca0edb41 arm64 updates for 5.12
- vDSO build improvements including support for building with BSD.
 
  - Cleanup to the AMU support code and initialisation rework to support
    cpufreq drivers built as modules.
 
  - Removal of synthetic frame record from exception stack when entering
    the kernel from EL0.
 
  - Add support for the TRNG firmware call introduced by Arm spec
    DEN0098.
 
  - Cleanup and refactoring across the board.
 
  - Avoid calling arch_get_random_seed_long() from
    add_interrupt_randomness()
 
  - Perf and PMU updates including support for Cortex-A78 and the v8.3
    SPE extensions.
 
  - Significant steps along the road to leaving the MMU enabled during
    kexec relocation.
 
  - Faultaround changes to initialise prefaulted PTEs as 'old' when
    hardware access-flag updates are supported, which drastically
    improves vmscan performance.
 
  - CPU errata updates for Cortex-A76 (#1463225) and Cortex-A55
    (#1024718)
 
  - Preparatory work for yielding the vector unit at a finer granularity
    in the crypto code, which in turn will one day allow us to defer
    softirq processing when it is in use.
 
  - Support for overriding CPU ID register fields on the command-line.
 -----BEGIN PGP SIGNATURE-----
 
 iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAmAmwZcQHHdpbGxAa2Vy
 bmVsLm9yZwAKCRC3rHDchMFjNLA1B/0XMwWUhmJ4ZPK4sr28YWHNGLuCFHDgkMKU
 dEmS806OF9d0J7fTczGsKdS4IKtXWko67Z0UGiPIStwfm0itSW2Zgbo9KZeDPqPI
 fH0s23nQKxUMyNW7b9p4cTV3YuGVMZSBoMug2jU2DEDpSqeGBk09NPi6inERBCz/
 qZxcqXTKxXbtOY56eJmq09UlFZiwfONubzuCrrUH7LU8ZBSInM/6Q4us/oVm4zYI
 Pnv996mtL4UxRqq/KoU9+cQ1zsI01kt9/coHwfCYvSpZEVAnTWtfECsJ690tr3mF
 TSKQLvOzxbDtU+HcbkNVKW0A38EIO1xXr8yXW9SJx6BJBkyb24xo
 =IwMb
 -----END PGP SIGNATURE-----

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:

 - vDSO build improvements including support for building with BSD.

 - Cleanup to the AMU support code and initialisation rework to support
   cpufreq drivers built as modules.

 - Removal of synthetic frame record from exception stack when entering
   the kernel from EL0.

 - Add support for the TRNG firmware call introduced by Arm spec
   DEN0098.

 - Cleanup and refactoring across the board.

 - Avoid calling arch_get_random_seed_long() from
   add_interrupt_randomness()

 - Perf and PMU updates including support for Cortex-A78 and the v8.3
   SPE extensions.

 - Significant steps along the road to leaving the MMU enabled during
   kexec relocation.

 - Faultaround changes to initialise prefaulted PTEs as 'old' when
   hardware access-flag updates are supported, which drastically
   improves vmscan performance.

 - CPU errata updates for Cortex-A76 (#1463225) and Cortex-A55
   (#1024718)

 - Preparatory work for yielding the vector unit at a finer granularity
   in the crypto code, which in turn will one day allow us to defer
   softirq processing when it is in use.

 - Support for overriding CPU ID register fields on the command-line.

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (85 commits)
  drivers/perf: Replace spin_lock_irqsave to spin_lock
  mm: filemap: Fix microblaze build failure with 'mmu_defconfig'
  arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+
  arm64: cpufeatures: Allow disabling of Pointer Auth from the command-line
  arm64: Defer enabling pointer authentication on boot core
  arm64: cpufeatures: Allow disabling of BTI from the command-line
  arm64: Move "nokaslr" over to the early cpufeature infrastructure
  KVM: arm64: Document HVC_VHE_RESTART stub hypercall
  arm64: Make kvm-arm.mode={nvhe, protected} an alias of id_aa64mmfr1.vh=0
  arm64: Add an aliasing facility for the idreg override
  arm64: Honor VHE being disabled from the command-line
  arm64: Allow ID_AA64MMFR1_EL1.VH to be overridden from the command line
  arm64: cpufeature: Add an early command-line cpufeature override facility
  arm64: Extract early FDT mapping from kaslr_early_init()
  arm64: cpufeature: Use IDreg override in __read_sysreg_by_encoding()
  arm64: cpufeature: Add global feature override facility
  arm64: Move SCTLR_EL1 initialisation to EL-agnostic code
  arm64: Simplify init_el2_state to be non-VHE only
  arm64: Move VHE-specific SPE setup to mutate_to_vhe()
  arm64: Drop early setting of MDSCR_EL2.TPMS
  ...
2021-02-21 13:08:42 -08:00
Linus Torvalds
d310ec03a3 The performance event updates for v5.12 are:
- Add CPU-PMU support for Intel Sapphire Rapids CPUs
 
  - Extend the perf ABI with PERF_SAMPLE_WEIGHT_STRUCT, to offer two-parameter
    sampling event feedback. Not used yet, but is intended for Golden Cove
    CPU-PMU, which can provide both the instruction latency and the cache
    latency information for memory profiling events.
 
  - Remove experimental, default-disabled perfmon-v4 counter_freezing support
    that could only be enabled via a boot option. The hardware is hopelessly
    broken, we'd like to make sure nobody starts relying on this, as it would
    only end in tears.
 
  - Fix energy/power events on Intel SPR platforms
 
  - Simplify the uprobes resume_execution() logic
 
  - Misc smaller fixes.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmAtf7kRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1iJ2xAAvygKF8hm/UAGyT2R3iEruO49wRrmUfgt
 13iBBA1DotKw2b8F5UN5MqjfwS8UgGKuAd8agvQ6XXANpnJ5mpy0nrzgjEXUx4j+
 sQUqL7vxSdZ5J3kKblSZ4QoMzLVYSUkEDmw818vsa4eFWN8z58FJsv+ySegIFbXx
 +I3hF1O9a8MERZBUz4T5xHlgcbSDGEX6EvYRcO+zZ0rXfARfo9StfHYv1V53j6iY
 EOotFEKEn/5naczAd/sQo1SE1IgHtX2cbjOaKF7LulgEwZQWHpdKq0gww6nFK5yz
 XMSE9oXAFXRkRCJbrSqC0Dvrrf8hdlxWbKYbj9L7XILoxw199AdOBDbliJm6P/UH
 6+JSEu/N4R0TFYc7TX6yef7ncw12e+64USjKOlWWwww97rVWWH1/tFTdlXhS6s+d
 jVI3yEECKyZlddrDdsetRdUj+QKyZQfDqbMXPXiDTv9P6AFqBvNLZYT0UPU3akk5
 jXueHJQYSSgqnN+eRaIwvm4ZYWa031YHJXxiq2E89RnzL4JJArBYaddpukgxTYka
 c6Tn8L7f4zP5Bghu7hHv5Vy69i1N/3YvzUoYc6ljjmapgAJzxzq/yoEKrBlKnjtA
 MrstHhnwnPJl+PKjlbLpjl74rtcCiKJxjVhm+a5UbEcYoVuzJ86lmQK2WrLaoCTU
 B/zFplUF8C4=
 =BCcg
 -----END PGP SIGNATURE-----

Merge tag 'perf-core-2021-02-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull performance event updates from Ingo Molnar:

 - Add CPU-PMU support for Intel Sapphire Rapids CPUs

 - Extend the perf ABI with PERF_SAMPLE_WEIGHT_STRUCT, to offer
   two-parameter sampling event feedback. Not used yet, but is intended
   for Golden Cove CPU-PMU, which can provide both the instruction
   latency and the cache latency information for memory profiling
   events.

 - Remove experimental, default-disabled perfmon-v4 counter_freezing
   support that could only be enabled via a boot option. The hardware is
   hopelessly broken, we'd like to make sure nobody starts relying on
   this, as it would only end in tears.

 - Fix energy/power events on Intel SPR platforms

 - Simplify the uprobes resume_execution() logic

 - Misc smaller fixes.

* tag 'perf-core-2021-02-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/rapl: Fix psys-energy event on Intel SPR platform
  perf/x86/rapl: Only check lower 32bits for RAPL energy counters
  perf/x86/rapl: Add msr mask support
  perf/x86/kvm: Add Cascade Lake Xeon steppings to isolation_ucodes[]
  perf/x86/intel: Support CPUID 10.ECX to disable fixed counters
  perf/x86/intel: Add perf core PMU support for Sapphire Rapids
  perf/x86/intel: Filter unsupported Topdown metrics event
  perf/x86/intel: Factor out intel_update_topdown_event()
  perf/core: Add PERF_SAMPLE_WEIGHT_STRUCT
  perf/intel: Remove Perfmon-v4 counter_freezing support
  x86/perf: Use static_call for x86_pmu.guest_get_msrs
  perf/x86/intel/uncore: With > 8 nodes, get pci bus die id from NUMA info
  perf/x86/intel/uncore: Store the logical die id instead of the physical die id.
  x86/kprobes: Do not decode opcode in resume_execution()
2021-02-21 12:49:32 -08:00
Linus Torvalds
657bd90c93 Scheduler updates for v5.12:
[ NOTE: unfortunately this tree had to be freshly rebased today,
         it's a same-content tree of 82891be90f3c (-next published)
         merged with v5.11.
 
         The main reason for the rebase was an authorship misattribution
         problem with a new commit, which we noticed in the last minute,
         and which we didn't want to be merged upstream. The offending
         commit was deep in the tree, and dependent commits had to be
         rebased as well. ]
 
 - Core scheduler updates:
 
   - Add CONFIG_PREEMPT_DYNAMIC: this in its current form adds the
     preempt=none/voluntary/full boot options (default: full),
     to allow distros to build a PREEMPT kernel but fall back to
     close to PREEMPT_VOLUNTARY (or PREEMPT_NONE) runtime scheduling
     behavior via a boot time selection.
 
     There's also the /debug/sched_debug switch to do this runtime.
 
     This feature is implemented via runtime patching (a new variant of static calls).
 
     The scope of the runtime patching can be best reviewed by looking
     at the sched_dynamic_update() function in kernel/sched/core.c.
 
     ( Note that the dynamic none/voluntary mode isn't 100% identical,
       for example preempt-RCU is available in all cases, plus the
       preempt count is maintained in all models, which has runtime
       overhead even with the code patching. )
 
     The PREEMPT_VOLUNTARY/PREEMPT_NONE models, used by the vast majority
     of distributions, are supposed to be unaffected.
 
   - Fix ignored rescheduling after rcu_eqs_enter(). This is a bug that
     was found via rcutorture triggering a hang. The bug is that
     rcu_idle_enter() may wake up a NOCB kthread, but this happens after
     the last generic need_resched() check. Some cpuidle drivers fix it
     by chance but many others don't.
 
     In true 2020 fashion the original bug fix has grown into a 5-patch
     scheduler/RCU fix series plus another 16 RCU patches to address
     the underlying issue of missed preemption events. These are the
     initial fixes that should fix current incarnations of the bug.
 
   - Clean up rbtree usage in the scheduler, by providing & using the following
     consistent set of rbtree APIs:
 
      partial-order; less() based:
        - rb_add(): add a new entry to the rbtree
        - rb_add_cached(): like rb_add(), but for a rb_root_cached
 
      total-order; cmp() based:
        - rb_find(): find an entry in an rbtree
        - rb_find_add(): find an entry, and add if not found
 
        - rb_find_first(): find the first (leftmost) matching entry
        - rb_next_match(): continue from rb_find_first()
        - rb_for_each(): iterate a sub-tree using the previous two
 
   - Improve the SMP/NUMA load-balancer: scan for an idle sibling in a single pass.
     This is a 4-commit series where each commit improves one aspect of the idle
     sibling scan logic.
 
   - Improve the cpufreq cooling driver by getting the effective CPU utilization
     metrics from the scheduler
 
   - Improve the fair scheduler's active load-balancing logic by reducing the number
     of active LB attempts & lengthen the load-balancing interval. This improves
     stress-ng mmapfork performance.
 
   - Fix CFS's estimated utilization (util_est) calculation bug that can result in
     too high utilization values
 
 - Misc updates & fixes:
 
    - Fix the HRTICK reprogramming & optimization feature
    - Fix SCHED_SOFTIRQ raising race & warning in the CPU offlining code
    - Reduce dl_add_task_root_domain() overhead
    - Fix uprobes refcount bug
    - Process pending softirqs in flush_smp_call_function_from_idle()
    - Clean up task priority related defines, remove *USER_*PRIO and
      USER_PRIO()
    - Simplify the sched_init_numa() deduplication sort
    - Documentation updates
    - Fix EAS bug in update_misfit_status(), which degraded the quality
      of energy-balancing
    - Smaller cleanups
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmAtHBsRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1itgg/+NGed12pgPjYBzesdou60Lvx7LZLGjfOt
 M1F1EnmQGn/hEH2fCY6ZoqIZQTVltm7GIcBNabzYTzlaHZsdtyuDUJBZyj19vTlk
 zekcj7WVt+qvfjChaNwEJhQ9nnOM/eohMgEOHMAAJd9zlnQvve7NOLQ56UDM+kn/
 9taFJ5ZPvb4avP6C5p3KivvKex6Bjof/Tl0m3utpNyPpI/qK3FyGxwdgCxU0yepT
 ABWQX5ZQCufFvo1bgnBPfqyzab4MqhoM3bNKBsLQfuAlssG1xRv4KQOev4dRwrt9
 pXJikV5C9yez5d2lGe5p0ltH5IZS/l9x2yI/ZQj3OUDTFyV1ic6WfFAqJgDzVF8E
 i/vvA4NPQiI241Bkps+ErcCw4aVOgiY6TWli74cHjLUIX0+As6aHrFWXGSxUmiHB
 WR+B8KmdfzRTTlhOxMA+cvlpZcKCfxWkJJmXzr/lDZzIuKPqM3QCE2wD9sixkfVo
 JNICT0IvZghWOdbMEfZba8Psh/e2LVI9RzdpEiuYJz1ZrVlt1hO0M6jBxY0hMz9n
 k54z81xODw0a8P2FHMtpmB1vhAeqCmvwA6DO8z0Oxs0DFi+KM2bLf2efHsCKafI+
 Bm5v9YFaOk/55R76hJVh+aYLlyFgFkKd+P/niJTPDnxOk3SqJuXvTrql1HeGHkNr
 kYgQa23dsZk=
 =pyaG
 -----END PGP SIGNATURE-----

Merge tag 'sched-core-2021-02-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "Core scheduler updates:

   - Add CONFIG_PREEMPT_DYNAMIC: this in its current form adds the
     preempt=none/voluntary/full boot options (default: full), to allow
     distros to build a PREEMPT kernel but fall back to close to
     PREEMPT_VOLUNTARY (or PREEMPT_NONE) runtime scheduling behavior via
     a boot time selection.

     There's also the /debug/sched_debug switch to do this runtime.

     This feature is implemented via runtime patching (a new variant of
     static calls).

     The scope of the runtime patching can be best reviewed by looking
     at the sched_dynamic_update() function in kernel/sched/core.c.

     ( Note that the dynamic none/voluntary mode isn't 100% identical,
       for example preempt-RCU is available in all cases, plus the
       preempt count is maintained in all models, which has runtime
       overhead even with the code patching. )

     The PREEMPT_VOLUNTARY/PREEMPT_NONE models, used by the vast
     majority of distributions, are supposed to be unaffected.

   - Fix ignored rescheduling after rcu_eqs_enter(). This is a bug that
     was found via rcutorture triggering a hang. The bug is that
     rcu_idle_enter() may wake up a NOCB kthread, but this happens after
     the last generic need_resched() check. Some cpuidle drivers fix it
     by chance but many others don't.

     In true 2020 fashion the original bug fix has grown into a 5-patch
     scheduler/RCU fix series plus another 16 RCU patches to address the
     underlying issue of missed preemption events. These are the initial
     fixes that should fix current incarnations of the bug.

   - Clean up rbtree usage in the scheduler, by providing & using the
     following consistent set of rbtree APIs:

       partial-order; less() based:
         - rb_add(): add a new entry to the rbtree
         - rb_add_cached(): like rb_add(), but for a rb_root_cached

       total-order; cmp() based:
         - rb_find(): find an entry in an rbtree
         - rb_find_add(): find an entry, and add if not found

         - rb_find_first(): find the first (leftmost) matching entry
         - rb_next_match(): continue from rb_find_first()
         - rb_for_each(): iterate a sub-tree using the previous two

   - Improve the SMP/NUMA load-balancer: scan for an idle sibling in a
     single pass. This is a 4-commit series where each commit improves
     one aspect of the idle sibling scan logic.

   - Improve the cpufreq cooling driver by getting the effective CPU
     utilization metrics from the scheduler

   - Improve the fair scheduler's active load-balancing logic by
     reducing the number of active LB attempts & lengthen the
     load-balancing interval. This improves stress-ng mmapfork
     performance.

   - Fix CFS's estimated utilization (util_est) calculation bug that can
     result in too high utilization values

  Misc updates & fixes:

   - Fix the HRTICK reprogramming & optimization feature

   - Fix SCHED_SOFTIRQ raising race & warning in the CPU offlining code

   - Reduce dl_add_task_root_domain() overhead

   - Fix uprobes refcount bug

   - Process pending softirqs in flush_smp_call_function_from_idle()

   - Clean up task priority related defines, remove *USER_*PRIO and
     USER_PRIO()

   - Simplify the sched_init_numa() deduplication sort

   - Documentation updates

   - Fix EAS bug in update_misfit_status(), which degraded the quality
     of energy-balancing

   - Smaller cleanups"

* tag 'sched-core-2021-02-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  sched,x86: Allow !PREEMPT_DYNAMIC
  entry/kvm: Explicitly flush pending rcuog wakeup before last rescheduling point
  entry: Explicitly flush pending rcuog wakeup before last rescheduling point
  rcu/nocb: Trigger self-IPI on late deferred wake up before user resume
  rcu/nocb: Perform deferred wake up before last idle's need_resched() check
  rcu: Pull deferred rcuog wake up to rcu_eqs_enter() callers
  sched/features: Distinguish between NORMAL and DEADLINE hrtick
  sched/features: Fix hrtick reprogramming
  sched/deadline: Reduce rq lock contention in dl_add_task_root_domain()
  uprobes: (Re)add missing get_uprobe() in __find_uprobe()
  smp: Process pending softirqs in flush_smp_call_function_from_idle()
  sched: Harden PREEMPT_DYNAMIC
  static_call: Allow module use without exposing static_call_key
  sched: Add /debug/sched_preempt
  preempt/dynamic: Support dynamic preempt with preempt= boot option
  preempt/dynamic: Provide irqentry_exit_cond_resched() static call
  preempt/dynamic: Provide preempt_schedule[_notrace]() static calls
  preempt/dynamic: Provide cond_resched() and might_resched() static calls
  preempt: Introduce CONFIG_PREEMPT_DYNAMIC
  static_call: Provide DEFINE_STATIC_CALL_RET0()
  ...
2021-02-21 12:35:04 -08:00