linux_dsm_epyc7002/arch
John David Anglin 9ef0f88fe5 parisc: Handle case where flush_cache_range is called with no context
Just when I had decided that flush_cache_range() was always called with
a valid context, Helge reported two cases where the
"BUG_ON(!vma->vm_mm->context);" was hit on the phantom buildd:

 kernel BUG at /mnt/sdb6/linux/linux-4.15.4/arch/parisc/kernel/cache.c:587!
 CPU: 1 PID: 3254 Comm: kworker/1:2 Tainted: G D 4.15.0-1-parisc64-smp #1 Debian 4.15.4-1+b1
 Workqueue: events free_ioctx
  IAOQ[0]: flush_cache_range+0x164/0x168
  IAOQ[1]: flush_cache_page+0x0/0x1c8
  RP(r2): unmap_page_range+0xae8/0xb88
 Backtrace:
  [<00000000404a6980>] unmap_page_range+0xae8/0xb88
  [<00000000404a6ae0>] unmap_single_vma+0xc0/0x188
  [<00000000404a6cdc>] zap_page_range_single+0x134/0x1f8
  [<00000000404a702c>] unmap_mapping_range+0x1cc/0x208
  [<0000000040461518>] truncate_pagecache+0x98/0x108
  [<0000000040461624>] truncate_setsize+0x9c/0xb8
  [<00000000405d7f30>] put_aio_ring_file+0x80/0x100
  [<00000000405d803c>] aio_free_ring+0x8c/0x290
  [<00000000405d82c0>] free_ioctx+0x80/0x180
  [<0000000040284e6c>] process_one_work+0x21c/0x668
  [<00000000402854c4>] worker_thread+0x20c/0x778
  [<0000000040291d44>] kthread+0x2d4/0x2e0
  [<0000000040204020>] end_fault_vector+0x20/0xc0

This indicates that we need to handle the no context case in
flush_cache_range() as we do in flush_cache_mm().

In thinking about this, I realized that we don't need to flush the TLB
when there is no context.  So, I added context checks to the large flush
cases in flush_cache_mm() and flush_cache_range().  The large flush case
occurs frequently in flush_cache_mm() and the change should improve fork
performance.

The v2 version of this change removes the BUG_ON from flush_cache_page()
by skipping the TLB flush when there is no context.  I also added code
to flush the TLB in flush_cache_mm() and flush_cache_range() when we
have a context that's not current.  Now all three routines handle TLB
flushes in a similar manner.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Helge Deller <deller@gmx.de>
2018-03-17 11:49:39 +01:00
..
alpha locking/xchg/alpha: Fix xchg() and cmpxchg() memory ordering bugs 2018-02-23 08:38:16 +01:00
arc ARC fixes for 4.16-rc4 2018-03-01 14:32:23 -08:00
arm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-05 11:29:24 -08:00
arm64 arm64 fixes: 2018-03-09 16:49:30 -08:00
blackfin unify {de,}mangle_poll(), get rid of kernel-side POLL... 2018-02-11 14:37:22 -08:00
c6x The core framework has a handful of patches this time around, mostly due 2018-02-01 16:56:07 -08:00
cris bug.h: work around GCC PR82365 in BUG() 2018-02-21 15:35:43 -08:00
frv unify {de,}mangle_poll(), get rid of kernel-side POLL... 2018-02-11 14:37:22 -08:00
h8300 The core framework has a handful of patches this time around, mostly due 2018-02-01 16:56:07 -08:00
hexagon The core framework has a handful of patches this time around, mostly due 2018-02-01 16:56:07 -08:00
ia64 ia64/err-inject: fix spelling mistake: "capapbilities" -> "capabilities" 2018-03-05 14:44:53 -08:00
m32r The core framework has a handful of patches this time around, mostly due 2018-02-01 16:56:07 -08:00
m68k bug.h: work around GCC PR82365 in BUG() 2018-02-21 15:35:43 -08:00
metag The core framework has a handful of patches this time around, mostly due 2018-02-01 16:56:07 -08:00
microblaze microblaze: switch to NO_BOOTMEM 2018-03-16 12:51:27 +01:00
mips MIPS fixes for 4.16-rc5 2018-03-08 10:03:12 -08:00
mn10300 The core framework has a handful of patches this time around, mostly due 2018-02-01 16:56:07 -08:00
nios2 nios2 update for v4.16-rc1 2018-02-11 13:52:32 -08:00
openrisc The core framework has a handful of patches this time around, mostly due 2018-02-01 16:56:07 -08:00
parisc parisc: Handle case where flush_cache_range is called with no context 2018-03-17 11:49:39 +01:00
powerpc KVM fixes for v4.16-rc5 2018-03-09 16:59:19 -08:00
riscv riscv/barrier: Define __smp_{mb,rmb,wmb} 2018-02-26 08:44:50 -08:00
s390 KVM fixes for v4.16-rc5 2018-03-09 16:59:19 -08:00
score arch/score/kernel/setup.c: combine two seq_printf() calls into one call in show_cpuinfo() 2018-02-06 18:32:47 -08:00
sh sh: fix build error for empty CONFIG_BUILTIN_DTB_SOURCE 2018-03-02 09:20:55 +09:00
sparc sparc64: Fix regression in pmdp_invalidate(). 2018-03-15 14:18:00 -07:00
tile The core framework has a handful of patches this time around, mostly due 2018-02-01 16:56:07 -08:00
um mconsole_proc(): don't mess with file->f_pos 2018-02-09 19:28:01 -08:00
unicore32 lib: optimize cpumask_next_and() 2018-02-06 18:32:44 -08:00
x86 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-03-11 14:59:23 -07:00
xtensa xtensa: support DMA buffers in high memory 2018-02-16 19:19:54 -08:00
.gitignore
Kconfig Makefile: introduce CONFIG_CC_STACKPROTECTOR_AUTO 2018-02-06 18:32:44 -08:00