diff options
author | Andrey Vagin | 2011-03-10 00:22:23 +0100 |
---|---|---|
committer | Ingo Molnar | 2011-03-10 09:41:40 +0100 |
commit | f86268549f424f83b9eb0963989270e14fbfc3de (patch) | |
tree | 55fb3f1755a5cb8d81daecfef3aa84bb4ea340e8 /fs/block_dev.c | |
parent | x86: Don't check for BIOS corruption in first 64K when there's no need to (diff) | |
download | kernel-qcow2-linux-f86268549f424f83b9eb0963989270e14fbfc3de.tar.gz kernel-qcow2-linux-f86268549f424f83b9eb0963989270e14fbfc3de.tar.xz kernel-qcow2-linux-f86268549f424f83b9eb0963989270e14fbfc3de.zip |
x86/mm: Handle mm_fault_error() in kernel space
mm_fault_error() should not execute oom-killer, if page fault
occurs in kernel space. E.g. in copy_from_user()/copy_to_user().
This would happen if we find ourselves in OOM on a
copy_to_user(), or a copy_from_user() which faults.
Without this patch, the kernels hangs up in copy_from_user(),
because OOM killer sends SIG_KILL to current process, but it
can't handle a signal while in syscall, then the kernel returns
to copy_from_user(), reexcute current command and provokes
page_fault again.
With this patch the kernel return -EFAULT from copy_from_user().
The code, which checks that page fault occurred in kernel space,
has been copied from do_sigbus().
This situation is handled by the same way on powerpc, xtensa,
tile, ...
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@kernel.org>
LKML-Reference: <201103092322.p29NMNPH001682@imap1.linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'fs/block_dev.c')
0 files changed, 0 insertions, 0 deletions