linux/arch/powerpc
Aneesh Kumar K.V 69e044dd75 powerpc: Fix possible deadlock on page fault
stack_grow_into/14082 is trying to acquire lock:
  (&mm->mmap_sem){++++++}, at: [<c000000000206d28>] .might_fault+0x78/0xe0

 but task is already holding lock:
  (&mm->mmap_sem){++++++}, at: [<c0000000007ffd8c>] .do_page_fault+0x24c/0x910

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

        CPU0
        ----
   lock(&mm->mmap_sem);
   lock(&mm->mmap_sem);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 1 lock held by stack_grow_into/14082:
  #0:  (&mm->mmap_sem){++++++}, at: [<c0000000007ffd8c>] .do_page_fault+0x24c/0x910

 stack backtrace:
 CPU: 21 PID: 14082 Comm: stack_grow_into Not tainted 3.10.0-10.el7.ppc64.debug #1
 Call Trace:
 [c0000003d396b850] [c000000000016e7c] .show_stack+0x7c/0x1f0 (unreliable)
 [c0000003d396b920] [c000000000813fc8] .dump_stack+0x28/0x3c
 [c0000003d396b990] [c000000000124b90] .__lock_acquire+0x1640/0x1800
 [c0000003d396bab0] [c00000000012570c] .lock_acquire+0xac/0x250
 [c0000003d396bb80] [c000000000206d54] .might_fault+0xa4/0xe0
 [c0000003d396bbf0] [c0000000007ffe2c] .do_page_fault+0x2ec/0x910
 [c0000003d396be30] [c0000000000092e8] handle_page_fault+0x10/0x30

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-11 11:39:37 +10:00
..
boot Merge remote-tracking branch 'agust/next' into next 2013-09-05 16:43:30 +10:00
configs powerpc/85xx: Add C293PCIE board support 2013-08-23 19:43:24 -05:00
crypto powerpc: Fix compile of sha1-powerpc-asm.S on 32-bit 2013-03-05 16:56:26 +11:00
include ARM: SoC platform changes for 3.12 2013-09-06 13:30:06 -07:00
kernel powerpc: Export cpu_to_chip_id() to fix build error 2013-09-11 11:39:37 +10:00
kvm Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2013-09-06 10:49:42 -07:00
lib powerpc: Unaligned stores and stmw are broken in emulation code 2013-08-27 14:36:08 +10:00
math-emu powerpc/math-emu: Fix load/store indexed emulation 2013-08-14 14:59:57 +10:00
mm powerpc: Fix possible deadlock on page fault 2013-09-11 11:39:37 +10:00
net ppc: bpf_jit: can call module_free() from any context 2013-05-20 14:03:50 -07:00
oprofile Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2013-09-06 10:49:42 -07:00
perf Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2013-09-06 10:49:42 -07:00
platforms xfs: update for v3.12-rc1 2013-09-09 11:19:09 -07:00
sysdev Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2013-09-06 10:49:42 -07:00
xmon powerpc/xmon: Fix printing of set of CPUs in xmon 2013-09-05 17:29:19 +10:00
Kconfig ARM: SoC platform changes for 3.12 2013-09-06 13:30:06 -07:00
Kconfig.debug Merge branch 'kconfig-diet' from Dave Hansen 2013-07-04 11:25:51 -07:00
Makefile powerpc/e500: Set -mcpu flag for 32-bit e500 2013-08-20 20:49:56 -05:00
relocs_check.pl Fix warning typo "CONFIG_RELCOATABLE" 2013-05-29 15:11:30 +02:00