Re: [PATCH] AB-BA deadlock between uidhash_lock and tasklist_lock.

[Linus Torvalds]

On Thu, 10 Mar 2005, Robin Holt wrote:
> 
> reparent_to_init() does write_lock_irq(&tasklist_lock) then calls
> switch_uid() which calls free_uid() which grabs the uidhash_lock.
> 
> Independent of that, we have seen a different cpu call free_uid as a
> result of sys_wait4 and, immediately after acquiring the uidhash_lock,
> receive a timer interrupt which eventually leads to an attempt to grab
> the tasklist_lock.

Hmm..  We fixed this already, and the current tree doesn't have this 
problem (and the fix was much simpler: just move "switch_uid()" to outside 
the tasklist_lock.

That fix was done late december last year (current BK revision: 
1.1938.446.38), and I really think your patch is stale. Please 
double-check,

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