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/arc | |
| 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/arc')
| -rw-r--r-- | arch/arc/mm/fault.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c index 689ffd86d5e9..9ff3b411c8c2 100644 --- a/arch/arc/mm/fault.c +++ b/arch/arc/mm/fault.c @@ -59,8 +59,7 @@ void do_page_fault(struct pt_regs *regs, int write, unsigned long address, struct mm_struct *mm = tsk->mm; siginfo_t info; int fault, ret; - unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE | - (write ? FAULT_FLAG_WRITE : 0); + unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; /* * We fault-in kernel-space virtual memory on-demand. The @@ -88,6 +87,8 @@ void do_page_fault(struct pt_regs *regs, int write, unsigned long address, if (in_atomic() || !mm) goto no_context; + if (user_mode(regs)) + flags |= FAULT_FLAG_USER; retry: down_read(&mm->mmap_sem); vma = find_vma(mm, address); @@ -115,6 +116,7 @@ good_area: if (write) { if (!(vma->vm_flags & VM_WRITE)) goto bad_area; + flags |= FAULT_FLAG_WRITE; } else { if (!(vma->vm_flags & (VM_READ | VM_EXEC))) goto bad_area; |