Re: swsusp regression [Was: 2.6.17-mm1]

[Andrew Morton <akpm@osdl.org>]

On Fri, 23 Jun 2006 11:10:21 +0200
Pavel Machek <pavel@ucw.cz> wrote:

> > Here's what I could hand copy (I've suppressed printk timing information):
> > x1b9/0x1be
> > <c0166e6b> sys_write+0x4b/0x75  <c010300f> sysenter_past_esp+0x54/0x75
> > Code: 05 c4 52 43 c0 31 53 43 c0 c3 8b 2d 68 6e 54 c0 8b 1d 60
> > 6e 54 c0 8b 35 6c 6e 54 c0 8b 3d 70 6e 54 c0 ff 35 74 6e 54 c0 9d c3 90 <e8>
> > 9d 2c ea ff e8 a2 ff ff ff 6a 03 e8 4c ab de ff 83 c4 04 c3
> > EIP: [<c043531c>] do_suspend_lowlevel+0x0/0x15 SS:ESP 0068:f7a0fea4
> > <3>BUG: sleeping function called from invalid context at include/linux/rwsem.h:43
> > in_atomic():0, irqs_disabled():1
> >  <c0103e56> show_trace+0x20/0x22  <c0103f5b> dump_stack+0x1e/0x20
> >  <c011aec7> __might_sleep+0x9e/0xa6  <c012b0cf> blocking_notifier_call_chain+0x1e/0x5b
> >  <c011f091> profile_task_exit+0x21/0x23  <c0120946> do_exit+0x1d/0x483
> >  <c0104432> do_divide_error+0x0/0xbf  <c0362c76> do_page_fault+0x3c4/0x752
> >  <c0103b2f> error_code+0x4f/0x54  <c013b33a> suspend_enter+0x2f/0x52
> >  <c013b3e0> enter_state+0x4b/0x8d  <c013b579> state_store+0xa0/0xa2
> >  <c01a54f1> subsys_attr_store+0x37/0x41  <c01a5772> flush_write_buffer+0x3c/046
> >  <c01a57e3> sysfs_write_file+0x67/0x8b  <c0166da6> vfs_write+0x1b9/0x1be
> >  <c0166e6b> sys_write+0x4b/0x75  <c010300f> sysenter_past_esp+0x54/0x75
> 
> That is not an oops, rather a kernel BUG().

It's not a BUG().  It's a BUG.

IOW, it's just a WARN_ON().  Ingo decided all the scary messages should
start with the text "BUG".  That doesn't correlate with BUG().  Confused
yet?

That trace is odd.  It kinda looks like we got a segfault when entering the
do_suspend_lowlevel() assembly.  Or something.

> Can you just remove
> might_sleep line and see what happens?
> 
> Unfortunately, backtrace does not tell me which notifier chain did
> that :-(. Are you using audit or something like that?

No, that's all a consequence of something which happened earlier.