Re: 2.6.4-rc1-mm[12] - dm_any_congested issues

Miquel van Smoorenburg
2004-03-06T03:09:19Z

In article <200403051754.i25Hsjg7015052@turing-police.cc.vt.edu>,
<Valdis.Kletnieks@vt.edu> wrote:
>On Tue, 02 Mar 2004 20:15:36 PST, Andrew Morton <akpm@osdl.org> said:
>
>(Added in -rc1-mm1 which I didn't try, problem noticed in -rc2-mm2)
>
>> queue-congestion-dm-implementation.patch
>> Implement queue congestion callout for device mapper
>
>This is causing the following trace every second or 2 on my laptop:
>
>Mar 4 17:47:26 turing-police kernel: Debug: sleeping function called
>from invalid context at include/linux/rwsem.h:43
>Of course backing it out makes the messages go away, since dm_any_congested()
>was added by that patch. This patch just not ready for prime time, or
>am I (as usual)
>managing to trip over some silly corner case due to odd configuration?

It's a bug. The new queue congestion function cannot sleep, yet
it calls parts of DM that can sleep (indirectly). This needs to
be fixed in DM (I think).
See https://www.redhat.com/archives/linux-lvm/2004-March/msg00033.html

Mike.