diff options
| author | Prashant Gaikwad <pgaikwad@nvidia.com> | 2013-08-12 16:09:13 +0530 |
|---|---|---|
| committer | Dan Willemsen <dwillemsen@nvidia.com> | 2013-09-14 13:44:01 -0700 |
| commit | af141cc49eb867c7f885052b29006de44c6d19e9 (patch) | |
| tree | e21792858af267f39061fd56fe19f255e9b742d8 /arch/m32r | |
| parent | aaf289f838d57bc2670447d2b9fafa88c85fb025 (diff) | |
UPSTREAM arch: mm: pass userspace fault flag to generic fault handler
Unlike global OOM handling, memory cgroup code will invoke the OOM killer
in any OOM situation because it has no way of telling faults occuring in
kernel context - which could be handled more gracefully - from
user-triggered faults.
Pass a flag that identifies faults originating in user space from the
architecture-specific fault handlers to generic code so that memcg OOM
handling can be improved.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: azurIt <azurit@pobox.sk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 407c454cb0ac6e68ca66974da787a71118cfef84)
Conflicts:
arch/arc/mm/fault.c
arch/arm64/mm/fault.c
arch/metag/mm/fault.c
arch/parisc/mm/fault.c
Change-Id: Iee53942737627be8dd8e2e325b5ba87fe85d6814
Signed-off-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Reviewed-on: http://git-master/r/266410
GVS: Gerrit_Virtual_Submit
Reviewed-by: Sachin Nikam <snikam@nvidia.com>
Diffstat (limited to 'arch/m32r')
| -rw-r--r-- | arch/m32r/mm/fault.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/arch/m32r/mm/fault.c b/arch/m32r/mm/fault.c index 3cdfa9c1d091..e9c6a8014bd6 100644 --- a/arch/m32r/mm/fault.c +++ b/arch/m32r/mm/fault.c @@ -78,7 +78,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code, struct mm_struct *mm; struct vm_area_struct * vma; unsigned long page, addr; - int write; + unsigned long flags = 0; int fault; siginfo_t info; @@ -117,6 +117,9 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code, if (in_atomic() || !mm) goto bad_area_nosemaphore; + if (error_code & ACE_USERMODE) + flags |= FAULT_FLAG_USER; + /* When running in the kernel we expect faults to occur only to * addresses in user space. All other faults represent errors in the * kernel and should generate an OOPS. Unfortunately, in the case of an @@ -166,14 +169,13 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code, */ good_area: info.si_code = SEGV_ACCERR; - write = 0; switch (error_code & (ACE_WRITE|ACE_PROTECTION)) { default: /* 3: write, present */ /* fall through */ case ACE_WRITE: /* write, not present */ if (!(vma->vm_flags & VM_WRITE)) goto bad_area; - write++; + flags |= FAULT_FLAG_WRITE; break; case ACE_PROTECTION: /* read, present */ case 0: /* read, not present */ @@ -194,7 +196,7 @@ good_area: */ addr = (address & PAGE_MASK); set_thread_fault_code(error_code); - fault = handle_mm_fault(mm, vma, addr, write ? FAULT_FLAG_WRITE : 0); + fault = handle_mm_fault(mm, vma, addr, flags); if (unlikely(fault & VM_FAULT_ERROR)) { if (fault & VM_FAULT_OOM) goto out_of_memory; |