lkml.org 
[lkml]   [2005]   [Feb]   [23]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
DateWed, 23 Feb 2005 07:54:06 -0800 (PST)
FromLinus Torvalds <>
SubjectRe: [PATCH/RFC] Futex mmap_sem deadlock

On Wed, 23 Feb 2005, Joe Korty wrote:
> 
> Perhaps this should be preempt_disable .... preempt_enable.

No, the problem with preempt_disable/enable is that they go away if 
preemption is not enabled. So you really do have to do it by hand with the 
"inc_preempt_count".

> Otherwise, a preempt attempt in get_user would not be seen
> until some future preempt_enable was executed.

True. I guess we should have a "preempt_check_resched()" there too. That's 
what "kunmap_atomic()" does too (which is what we rely on in the other 
case we do this..)

		Linus
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:10    [from the cache]
©2003-2008