diff options
| author | Johannes Weiner <hannes@cmpxchg.org> | 2013-09-12 15:13:39 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-11-21 09:22:56 -0800 |
| commit | e2ec2c2b96808afa2f57ec7d7949691146fca341 (patch) | |
| tree | 9056b3be2fc19f9a00993a01507776a97b7d3ebd /arch/cris | |
| parent | 086c6cc5377d0908667e8f7082633aebf45cf95f (diff) | |
arch: mm: pass userspace fault flag to generic fault handler
commit 759496ba6407c6994d6a5ce3a5e74937d7816208 upstream.
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>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/cris')
| -rw-r--r-- | arch/cris/mm/fault.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/cris/mm/fault.c b/arch/cris/mm/fault.c index 73312ab6c696..1790f22e71a2 100644 --- a/arch/cris/mm/fault.c +++ b/arch/cris/mm/fault.c @@ -58,8 +58,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs, struct vm_area_struct * vma; siginfo_t info; int fault; - unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE | - ((writeaccess & 1) ? FAULT_FLAG_WRITE : 0); + unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; D(printk(KERN_DEBUG "Page fault for %lX on %X at %lX, prot %d write %d\n", @@ -117,6 +116,8 @@ do_page_fault(unsigned long address, struct pt_regs *regs, 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); @@ -155,6 +156,7 @@ retry: } else if (writeaccess == 1) { 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; |