Commit Graph

84 Commits

Author SHA1 Message Date
Joe Perches 55bd9ac468 powerpc/mm: Fix typo in IS_ENABLED()
IS_ENABLED() matches names exactly, so the missing "CONFIG_" prefix
means this code would never be built.

Also fixes a missing newline in pr_warn().

Fixes: 970d54f99c ("powerpc/book3s64/hash: Disable 16M linear mapping size if not aligned")
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/202006050717.A2F9809E@keescook
2020-06-22 10:37:58 +10:00
Mike Rapoport 65fddcfca8 mm: reorder includes after introduction of linux/pgtable.h
The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include
of the latter in the middle of asm includes.  Fix this up with the aid of
the below script and manual adjustments here and there.

	import sys
	import re

	if len(sys.argv) is not 3:
	    print "USAGE: %s <file> <header>" % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include <linux/%s>" % sys.argv[2]
	moved = False
	in_hdrs = False

	with open(sys.argv[1], "r") as f:
	    lines = f.readlines()
	    for _line in lines:
		line = _line.rstrip('
')
		if line == hdr_to_move:
		    continue
		if line.startswith("#include <linux/"):
		    in_hdrs = True
		elif not moved and in_hdrs:
		    moved = True
		    print hdr_to_move
		print line

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport ca5999fde0 mm: introduce include/linux/pgtable.h
The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.

Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Nicholas Piggin 18594f9b8c powerpc/64s/radix: Don't prefetch DAR in update_mmu_cache
The idea behind this prefetch was to kick off a page table walk before
returning from the fault, getting some pipelining advantage.

But this never showed up any noticable performance advantage, and in
fact with KUAP the prefetches are actually blocked and cause some
kind of micro-architectural fault. Removing this improves page fault
microbenchmark performance by about 9%.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Keep the early return in update_mmu_cache()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200504122907.49304-1-npiggin@gmail.com
2020-05-28 23:24:34 +10:00
Nicholas Piggin 82a1b8ed56 powerpc/64s/hash: Add stress_slb kernel boot option to increase SLB faults
This option increases the number of SLB misses by limiting the number
of kernel SLB entries, and increased flushing of cached lookaside
information. This helps stress test difficult to hit paths in the
kernel.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Relocate the code into arch/powerpc/mm, s/torture/stress/]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200511125825.3081305-1-mpe@ellerman.id.au
2020-05-20 23:39:58 +10:00
Aneesh Kumar K.V 2f92447f9f powerpc/book3s64/hash: Use the pte_t address from the caller
Don't fetch the pte value using lockless page table walk. Instead use the value from the
caller. hash_preload is called with ptl lock held. So it is safe to use the
pte_t address directly.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-6-aneesh.kumar@linux.ibm.com
2020-05-05 21:20:14 +10:00
Aneesh Kumar K.V ec4abf1e70 powerpc/mm/hash64: use _PAGE_PTE when checking for pte_present
This makes the pte_present check stricter by checking for additional _PAGE_PTE
bit. A level 1 pte pointer (THP pte) can be switched to a pointer to level 0 pte
page table page by following two operations.

1) THP split.
2) madvise(MADV_DONTNEED) in parallel to page fault.

A lockless page table walk need to make sure we can handle such changes
gracefully.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-4-aneesh.kumar@linux.ibm.com
2020-05-05 21:20:14 +10:00
Aneesh Kumar K.V fe4a6856cb powerpc/pkeys: Avoid using lockless page table walk
Fetch pkey from vma instead of linux page table. Also document the fact that in
some cases the pkey returned in siginfo won't be the same as the one we took
keyfault on. Even with linux page table walk, we can end up in a similar scenario.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-2-aneesh.kumar@linux.ibm.com
2020-05-05 21:20:13 +10:00
Logan Gunthorpe 4e00c5affd powerpc/mm: thread pgprot_t through create_section_mapping()
In prepartion to support a pgprot_t argument for arch_add_memory().

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric Badger <ebadger@gigaio.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200306170846.9333-6-logang@deltatee.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Greg Kroah-Hartman 08f6a7974a powerpc/mm: book3s64: hash_utils: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200209105901.1620958-3-gregkh@linuxfoundation.org
2020-03-04 22:44:25 +11:00
Russell Currey 970d54f99c powerpc/book3s64/hash: Disable 16M linear mapping size if not aligned
With STRICT_KERNEL_RWX on in a relocatable kernel under the hash MMU,
if the position the kernel is loaded at is not 16M aligned things go
horribly wrong. Specifically hash__mark_initmem_nx() will call
hash__change_memory_range() which then aligns down the start address,
and due to the text not being 16M aligned causes some of the kernel
text to be marked non-executable.

We can avoid this when selecting the linear mapping size, so do so and
print a warning. I tested this for various alignments and as long as
the position is 64K aligned it's fine (the base requirement for
powerpc).

Signed-off-by: Russell Currey <ruscur@russell.cc>
[mpe: Add details of the failure mode]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191224064126.183670-1-ruscur@russell.cc
2020-01-16 14:59:36 +10:00
Aneesh Kumar K.V 16f6b67cf0 powerpc/book3s64/hash: Add cond_resched to avoid soft lockup warning
With large memory (8TB and more) hotplug, we can get soft lockup
warnings as below. These were caused by a long loop without any
explicit cond_resched which is a problem for !PREEMPT kernels.

Avoid this using cond_resched() while inserting hash page table
entries. We already do similar cond_resched() in __add_pages(), see
commit f64ac5e6e3 ("mm, memory_hotplug: add scheduling point to
__add_pages").

  rcu:     3-....: (24002 ticks this GP) idle=13e/1/0x4000000000000002 softirq=722/722 fqs=12001
   (t=24003 jiffies g=4285 q=2002)
  NMI backtrace for cpu 3
  CPU: 3 PID: 3870 Comm: ndctl Not tainted 5.3.0-197.18-default+ #2
  Call Trace:
    dump_stack+0xb0/0xf4 (unreliable)
    nmi_cpu_backtrace+0x124/0x130
    nmi_trigger_cpumask_backtrace+0x1ac/0x1f0
    arch_trigger_cpumask_backtrace+0x28/0x3c
    rcu_dump_cpu_stacks+0xf8/0x154
    rcu_sched_clock_irq+0x878/0xb40
    update_process_times+0x48/0x90
    tick_sched_handle.isra.16+0x4c/0x80
    tick_sched_timer+0x68/0xe0
    __hrtimer_run_queues+0x180/0x430
    hrtimer_interrupt+0x110/0x300
    timer_interrupt+0x108/0x2f0
    decrementer_common+0x114/0x120
  --- interrupt: 901 at arch_add_memory+0xc0/0x130
      LR = arch_add_memory+0x74/0x130
    memremap_pages+0x494/0x650
    devm_memremap_pages+0x3c/0xa0
    pmem_attach_disk+0x188/0x750
    nvdimm_bus_probe+0xac/0x2c0
    really_probe+0x148/0x570
    driver_probe_device+0x19c/0x1d0
    device_driver_attach+0xcc/0x100
    bind_store+0x134/0x1c0
    drv_attr_store+0x44/0x60
    sysfs_kf_write+0x64/0x90
    kernfs_fop_write+0x1a0/0x270
    __vfs_write+0x3c/0x70
    vfs_write+0xd0/0x260
    ksys_write+0xdc/0x130
    system_call+0x5c/0x68

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191001084656.31277-1-aneesh.kumar@linux.ibm.com
2019-11-05 22:24:57 +11:00
Aneesh Kumar K.V d78d5dace5 powerpc/book3s64/hash: Use secondary hash for bolted mapping if the primary is full
With bolted hash page table entry, kernel currently only use primary hash group
when inserting the hash page table entry. In the rare case where kernel find all the
8 primary hash slot occupied by bolted entries, this can result in hash page
table insert failure for bolted entries. Avoid this by using the secondary hash
group.

This is different from what kernel does for the non-bolted mapping. With
non-bolted entries kernel will try secondary before removing an existing entry
from hash page table group. With bolted prefer primary hash group and hence
try to insert the page table entry by removing a slot from primary before trying
the secondary hash group.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191024093542.29777-3-aneesh.kumar@linux.ibm.com
2019-10-28 21:54:16 +11:00
Aneesh Kumar K.V 75838a3290 powerpc/pseries: Don't fail hash page table insert for bolted mapping
If the hypervisor returned H_PTEG_FULL for H_ENTER hcall, retry a hash page table
insert by removing a random entry from the group.

After some runtime, it is very well possible to find all the 8 hash page table
entry slot in the hpte group used for mapping. Don't fail a bolted entry insert
in that case. With Storage class memory a user can find this error easily since
a namespace enable/disable is equivalent to memory add/remove.

This results in failures as reported below:

$ ndctl create-namespace -r region1 -t pmem -m devdax -a 65536 -s 100M
libndctl: ndctl_dax_enable: dax1.3: failed to enable
  Error: namespace1.2: failed to enable

failed to create namespace: No such device or address

In kernel log we find the details as below:

Unable to create mapping for hot added memory 0xc000042006000000..0xc00004200d000000: -1
dax_pmem: probe of dax1.3 failed with error -14

This indicates that we failed to create a bolted hash table entry for direct-map
address backing the namespace.

We also observe failures such that not all namespaces will be enabled with
ndctl enable-namespace all command.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191024093542.29777-2-aneesh.kumar@linux.ibm.com
2019-10-28 21:54:16 +11:00
Kefeng Wang 9ef258bad7 thp: update split_huge_page_pmd() comment
According to 78ddc53473 ("thp: rename split_huge_page_pmd() to
split_huge_pmd()"), update related comment.

Link: http://lkml.kernel.org/r/20190731033406.185285-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24 15:54:10 -07:00
Michael Ellerman dac39f7885 powerpc/64s: Remove overlaps_kvm_tmp()
kvm_tmp is now in .text and so doesn't need a special overlap check.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190911115746.12433-2-mpe@ellerman.id.au
2019-09-14 00:04:40 +10:00
Nicholas Piggin 7d805accbe powerpc/64s: remove unnecessary translation cache flushes at boot
The various translation structure invalidations performed in early boot
when the MMU is off are not required, because everything is invalidated
immediately before a CPU first enables its MMU (see early_init_mmu
and early_init_mmu_secondary).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-6-npiggin@gmail.com
2019-09-05 14:22:41 +10:00
Nicholas Piggin fd13daea5f powerpc/64s: make mmu_partition_table_set_entry TLB flush optional
No functional change.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-4-npiggin@gmail.com
2019-09-05 14:22:40 +10:00
Nicholas Piggin ed6546bdc6 powerpc/64s: remove register_process_table callback
This callback is only required because the partition table init comes
before process table allocation on powernv (aka bare metal aka native).

Change the order to allocate the process table first, and remove the
callback.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-2-npiggin@gmail.com
2019-09-05 14:22:40 +10:00
Nicholas Piggin 9b123d1ea2 powerpc/64s/exception: reduce page fault unnecessary loads
This avoids 3 loads in the radix page fault case, 1 load in the
hash fault case, and 2 loads in the hash miss page fault case.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190802105709.27696-37-npiggin@gmail.com
2019-08-30 11:14:59 +10:00
Michael Ellerman 9044adca78 Merge branch 'topic/ppc-kvm' into next
Merge our ppc-kvm topic branch to bring in the Ultravisor support
patches.
2019-08-30 09:52:57 +10:00
Claudio Carvalho 5223134029 powerpc/mm: Write to PTCR only if ultravisor disabled
In ultravisor enabled systems, PTCR becomes ultravisor privileged only
for writing and an attempt to write to it will cause a Hypervisor
Emulation Assitance interrupt.

This patch uses the set_ptcr_when_no_uv() function to restrict PTCR
writing to only when ultravisor is disabled.

Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190822034838.27876-6-cclaudio@linux.ibm.com
2019-08-30 09:40:16 +10:00
Christophe Leroy e5a1edb9fe powerpc/mm: move update_mmu_cache() into book3s hash utils.
update_mmu_cache() is only for BOOK3S, and can be simplified for
BOOK3S32.

Move it out of mem.c into respective BOOK3S32 and BOOK3S64 files
containing hash utils.

BOOK3S64 version of hash_preload() is only used locally, declare it
static.

Remove the radix_enabled() stuff in BOOK3S32 version.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/107aaf43583a5f5d09e0d4e84c4c4390ecfcd512.1565933217.git.christophe.leroy@c-s.fr
2019-08-20 21:22:14 +10:00
Gautham R. Shenoy c784be435d powerpc/pseries: Fix cpu_hotplug_lock acquisition in resize_hpt()
The calls to arch_add_memory()/arch_remove_memory() are always made
with the read-side cpu_hotplug_lock acquired via memory_hotplug_begin().
On pSeries, arch_add_memory()/arch_remove_memory() eventually call
resize_hpt() which in turn calls stop_machine() which acquires the
read-side cpu_hotplug_lock again, thereby resulting in the recursive
acquisition of this lock.

In the absence of CONFIG_PROVE_LOCKING, we hadn't observed a system
lockup during a memory hotplug operation because cpus_read_lock() is a
per-cpu rwsem read, which, in the fast-path (in the absence of the
writer, which in our case is a CPU-hotplug operation) simply
increments the read_count on the semaphore. Thus a recursive read in
the fast-path doesn't cause any problems.

However, we can hit this problem in practice if there is a concurrent
CPU-Hotplug operation in progress which is waiting to acquire the
write-side of the lock. This will cause the second recursive read to
block until the writer finishes. While the writer is blocked since the
first read holds the lock. Thus both the reader as well as the writers
fail to make any progress thereby blocking both CPU-Hotplug as well as
Memory Hotplug operations.

Memory-Hotplug				CPU-Hotplug
CPU 0					CPU 1
------                                  ------

1. down_read(cpu_hotplug_lock.rw_sem)
   [memory_hotplug_begin]
					2. down_write(cpu_hotplug_lock.rw_sem)
					[cpu_up/cpu_down]
3. down_read(cpu_hotplug_lock.rw_sem)
   [stop_machine()]

Lockdep complains as follows in these code-paths.

 swapper/0/1 is trying to acquire lock:
 (____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: stop_machine+0x2c/0x60

but task is already holding lock:
(____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: mem_hotplug_begin+0x20/0x50

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(cpu_hotplug_lock.rw_sem);
   lock(cpu_hotplug_lock.rw_sem);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 3 locks held by swapper/0/1:
  #0: (____ptrval____) (&dev->mutex){....}, at: __driver_attach+0x12c/0x1b0
  #1: (____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: mem_hotplug_begin+0x20/0x50
  #2: (____ptrval____) (mem_hotplug_lock.rw_sem){++++}, at: percpu_down_write+0x54/0x1a0

stack backtrace:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc5-58373-gbc99402235f3-dirty #166
 Call Trace:
   dump_stack+0xe8/0x164 (unreliable)
   __lock_acquire+0x1110/0x1c70
   lock_acquire+0x240/0x290
   cpus_read_lock+0x64/0xf0
   stop_machine+0x2c/0x60
   pseries_lpar_resize_hpt+0x19c/0x2c0
   resize_hpt_for_hotplug+0x70/0xd0
   arch_add_memory+0x58/0xfc
   devm_memremap_pages+0x5e8/0x8f0
   pmem_attach_disk+0x764/0x830
   nvdimm_bus_probe+0x118/0x240
   really_probe+0x230/0x4b0
   driver_probe_device+0x16c/0x1e0
   __driver_attach+0x148/0x1b0
   bus_for_each_dev+0x90/0x130
   driver_attach+0x34/0x50
   bus_add_driver+0x1a8/0x360
   driver_register+0x108/0x170
   __nd_driver_register+0xd0/0xf0
   nd_pmem_driver_init+0x34/0x48
   do_one_initcall+0x1e0/0x45c
   kernel_init_freeable+0x540/0x64c
   kernel_init+0x2c/0x160
   ret_from_kernel_thread+0x5c/0x68

Fix this issue by
  1) Requiring all the calls to pseries_lpar_resize_hpt() be made
     with cpu_hotplug_lock held.

  2) In pseries_lpar_resize_hpt() invoke stop_machine_cpuslocked()
     as a consequence of 1)

  3) To satisfy 1), in hpt_order_set(), call mmu_hash_ops.resize_hpt()
     with cpu_hotplug_lock held.

Fixes: dbcf929c00 ("powerpc/pseries: Add support for hash table resizing")
Cc: stable@vger.kernel.org # v4.11+
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1557906352-29048-1-git-send-email-ego@linux.vnet.ibm.com
2019-08-19 13:20:23 +10:00
Nicholas Piggin 2b87a2553a powerpc/64s: Make boot look nice(r)
Radix boot looks like this:

 -----------------------------------------------------
 phys_mem_size     = 0x200000000
 dcache_bsize      = 0x80
 icache_bsize      = 0x80
 cpu_features      = 0x0000c06f8f5fb1a7
   possible        = 0x0000fbffcf5fb1a7
   always          = 0x00000003800081a1
 cpu_user_features = 0xdc0065c2 0xaee00000
 mmu_features      = 0xbc006041
 firmware_features = 0x0000000010000000
 hash-mmu: ppc64_pft_size    = 0x0
 hash-mmu: kernel vmalloc start   = 0xc008000000000000
 hash-mmu: kernel IO start        = 0xc00a000000000000
 hash-mmu: kernel vmemmap start   = 0xc00c000000000000
 -----------------------------------------------------

Fix:

 -----------------------------------------------------
 phys_mem_size     = 0x200000000
 dcache_bsize      = 0x80
 icache_bsize      = 0x80
 cpu_features      = 0x0000c06f8f5fb1a7
   possible        = 0x0000fbffcf5fb1a7
   always          = 0x00000003800081a1
 cpu_user_features = 0xdc0065c2 0xaee00000
 mmu_features      = 0xbc006041
 firmware_features = 0x0000000010000000
 vmalloc start     = 0xc008000000000000
 IO start          = 0xc00a000000000000
 vmemmap start     = 0xc00c000000000000
 -----------------------------------------------------

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190516020437.11783-1-npiggin@gmail.com
2019-08-15 22:52:55 +10:00
Suraj Jitindar Singh da0ef93310 powerpc/mm: Limit rma_size to 1TB when running without HV mode
The virtual real mode addressing (VRMA) mechanism is used when a
partition is using HPT (Hash Page Table) translation and performs real
mode accesses (MSR[IR|DR] = 0) in non-hypervisor mode. In this mode
effective address bits 0:23 are treated as zero (i.e. the access is
aliased to 0) and the access is performed using an implicit 1TB SLB
entry.

The size of the RMA (Real Memory Area) is communicated to the guest as
the size of the first memory region in the device tree. And because of
the mechanism described above can be expected to not exceed 1TB. In
the event that the host erroneously represents the RMA as being larger
than 1TB, guest accesses in real mode to memory addresses above 1TB
will be aliased down to below 1TB. This means that a memory access
performed in real mode may differ to one performed in virtual mode for
the same memory address, which would likely have unintended
consequences.

To avoid this outcome have the guest explicitly limit the size of the
RMA to the current maximum, which is 1TB. This means that even if the
first memory block is larger than 1TB, only the first 1TB should be
accessed in real mode.

Fixes: c610d65c0a ("powerpc/pseries: lift RTAS limit for hash")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190710052018.14628-1-sjitindarsingh@gmail.com
2019-07-15 12:41:17 +10:00
Linus Torvalds 192f0f8e9d powerpc updates for 5.3
Notable changes:
 
  - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver, as well
    as some other functions only used by drivers that haven't (yet?) made it
    upstream.
 
  - A fix for a bug in our handling of hardware watchpoints (eg. perf record -e
    mem: ...) which could lead to register corruption and kernel crashes.
 
  - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for vmalloc
    when using the Radix MMU.
 
  - A large but incremental rewrite of our exception handling code to use gas
    macros rather than multiple levels of nested CPP macros.
 
 And the usual small fixes, cleanups and improvements.
 
 Thanks to:
   Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju
   T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Cédric Le Goater,
   Christian Lamparter, Christophe Leroy, Christophe Lombard, Christoph Hellwig,
   Daniel Axtens, Denis Efremov, Enrico Weigelt, Frederic Barrat, Gautham R.
   Shenoy, Geert Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg
   Kurz, Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
   Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N. Rao,
   Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi Bangoria,
   Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher Boessenkool, Shaokun
   Zhang, Shawn Anastasio, Stewart Smith, Suraj Jitindar Singh, Thiago Jung
   Bauermann, YueHaibing.
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Merge tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver,
     as well as some other functions only used by drivers that haven't
     (yet?) made it upstream.

   - A fix for a bug in our handling of hardware watchpoints (eg. perf
     record -e mem: ...) which could lead to register corruption and
     kernel crashes.

   - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for
     vmalloc when using the Radix MMU.

   - A large but incremental rewrite of our exception handling code to
     use gas macros rather than multiple levels of nested CPP macros.

  And the usual small fixes, cleanups and improvements.

  Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab,
  Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann,
  Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe
  Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis
  Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert
  Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz,
  Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
  Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N.
  Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi
  Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher
  Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj
  Jitindar Singh, Thiago Jung Bauermann, YueHaibing"

* tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits)
  powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state.
  powerpc/eeh: Handle hugepages in ioremap space
  ocxl: Update for AFU descriptor template version 1.1
  powerpc/boot: pass CONFIG options in a simpler and more robust way
  powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
  powerpc/irq: Don't WARN continuously in arch_local_irq_restore()
  powerpc/module64: Use symbolic instructions names.
  powerpc/module32: Use symbolic instructions names.
  powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h
  powerpc/module64: Fix comment in R_PPC64_ENTRY handling
  powerpc/boot: Add lzo support for uImage
  powerpc/boot: Add lzma support for uImage
  powerpc/boot: don't force gzipped uImage
  powerpc/8xx: Add microcode patch to move SMC parameter RAM.
  powerpc/8xx: Use IO accessors in microcode programming.
  powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c
  powerpc/8xx: refactor programming of microcode CPM params.
  powerpc/8xx: refactor printing of microcode patch name.
  powerpc/8xx: Refactor microcode write
  powerpc/8xx: refactor writing of CPM microcode arrays
  ...
2019-07-13 16:08:36 -07:00
Aneesh Kumar K.V 78c9498885 powerpc/mm/hash/4k: Don't use 64K page size for vmemmap with 4K pagesize
With hash translation and 4K PAGE_SIZE config, we need to make sure we don't
use 64K page size for vmemmap.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-05 00:27:20 +10:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
YueHaibing d667edc01b powerpc/mm: Make some symbols static that can be
Noticed by sparse.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-28 12:08:10 +10:00
Christophe Leroy e4dccf9092 powerpc/mm: print hash info in a helper
Reduce #ifdef mess by defining a helper to print
hash info at startup.

In the meantime, remove the display of hash table address
to reduce leak of non necessary information.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:26 +10:00
Christophe Leroy 45d0ba527b powerpc/mm: move hugetlb_disabled into asm/hugetlb.h
No need to have this in asm/page.h, move it into asm/hugetlb.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:24 +10:00
Christophe Leroy 5953fb4f46 powerpc/mm: define subarch SLB_ADDR_LIMIT_DEFAULT
This patch defines a subarch specific SLB_ADDR_LIMIT_DEFAULT
to remove the #ifdefs around the setup of mm->context.slb_addr_limit

It also generalises the use of mm_ctx_set_slb_addr_limit() helper.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:23 +10:00
Christophe Leroy 47d99948ee powerpc/mm: Move book3s64 specifics in subdirectory mm/book3s64
Many files in arch/powerpc/mm are only for book3S64. This patch
creates a subdirectory for them.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Update the selftest sym links, shorten new filenames, cleanup some
      whitespace and formatting in the new files.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:18:38 +10:00