Subject: Re: [PATCH 02.5] mm: sl[au]b: first remove PFMEMALLOC flag then SLAB flag

From: Cong Wang <[email-masked]>
Date: Sat, 16 Jun 2012 08:14:10 +0000 (UTC)

On Fri, 15 Jun 2012 at 15:54 GMT, Sebastian Andrzej Siewior <[email-masked]> wrote:
> From: Sebastian Andrzej Siewior <[email-masked]>
>
> If we first remove the SLAB flag followed by the PFMEMALLOC flag then the
> removal of the latter will trigger the VM_BUG_ON() as it can be seen in
>| kernel BUG at include/linux/page-flags.h:474!
>| invalid opcode: 0000 [#1] PREEMPT SMP
>| Call Trace:
>|  [<c10e2d77>] slab_destroy+0x27/0x70
>|  [<c10e3285>] drain_freelist+0x55/0x90
>|  [<c10e344e>] __cache_shrink+0x6e/0x90
>|  [<c14e3211>] ? acpi_sleep_init+0xcf/0xcf
>|  [<c10e349d>] kmem_cache_shrink+0x2d/0x40
>
> because the SLAB flag is gone. This patch simply changes the order.
>

It would be nicer if we add some comments in the code. ;)

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to [email-masked].  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email-masked]"> [email-masked] </a>