[PATCH] fix OOM killing of swapoff

These days, if you swapoff when there isn't enough memory, OOM killer gives
"BUG: scheduling while atomic" and the machine hangs: badness() needs to do
its PF_SWAPOFF return after the task_unlock (tasklist_lock is also held
here, so p isn't going to be freed: PF_SWAPOFF might get turned off at any
moment, but that doesn't really matter).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Hugh Dickins 2007-01-05 16:37:03 -08:00 committed by Linus Torvalds
parent c8af57eb76
commit 7ba3485947

View File

@ -60,12 +60,6 @@ unsigned long badness(struct task_struct *p, unsigned long uptime)
return 0;
}
/*
* swapoff can easily use up all memory, so kill those first.
*/
if (p->flags & PF_SWAPOFF)
return ULONG_MAX;
/*
* The memory size of the process is the basis for the badness.
*/
@ -76,6 +70,12 @@ unsigned long badness(struct task_struct *p, unsigned long uptime)
*/
task_unlock(p);
/*
* swapoff can easily use up all memory, so kill those first.
*/
if (p->flags & PF_SWAPOFF)
return ULONG_MAX;
/*
* Processes which fork a lot of child processes are likely
* a good choice. We add half the vmsize of the children if they