Re: BUG: sleeping function called from invalid context at kernel/mutex.c:271

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

On Tue, Apr 17, 2012 at 10:56:27PM -0400, Steven Rostedt wrote:
> On Mon, Apr 16, 2012 at 01:27:24PM +0600, Alexander E. Patrakov wrote:
> > Hello.
> > 
> > With linux-3.3.0, my computer at work is rather unstable. The kernel
> 
> Have you tried other kernels? The leak just started with 3.3?
> 
> > seems to leak memory, however, kmemleak finds nothing significant.
> > 
> > Finally, the computer started swapping heavily and responded only via
> > ssh. In dmesg, I found this (repeated every two seconds):
> > 
> > [ 6709.483956] BUG: sleeping function called from invalid context at
> > kernel/mutex.c:271
> > [ 6709.483968] in_atomic(): 0, irqs_disabled(): 0, pid: 1210, name:
> 
> I'm a little baffled here, as preempt_count() is zero (in_atomic) and
> irqs are not disabled.
> 
> > NetworkManager
> 
> Ah there's your problem! (just kidding)
> 
> 
> > [ 6709.483974] INFO: lockdep is turned off.
> > [ 6709.483981] Pid: 1210, comm: NetworkManager Tainted: G          I
> > 3.3.0-gentoo #4
> > [ 6709.483987] Call Trace:
> > [ 6709.484006]  [<ffffffff810683fc>] __might_sleep+0xff/0x103
> > [ 6709.484019]  [<ffffffff81548783>] mutex_lock_nested+0x2a/0x2ff
> > [ 6709.484031]  [<ffffffff811261b5>] ? fget_light+0x6a/0x118
> > [ 6709.484043]  [<ffffffff8115a738>] inotify_poll+0x35/0x53
> > [ 6709.484052]  [<ffffffff81135eb1>] do_sys_poll+0x266/0x3f2
> > [ 6709.484060]  [<ffffffff81134e33>] ? poll_freewait+0x8f/0x8f
> > [ 6709.484069]  [<ffffffff81134efa>] ? __pollwait+0xc7/0xc7
> > [ 6709.484076]  [<ffffffff81134efa>] ? __pollwait+0xc7/0xc7
> > [ 6709.484084]  [<ffffffff81134efa>] ? __pollwait+0xc7/0xc7
> > [ 6709.484092]  [<ffffffff81134efa>] ? __pollwait+0xc7/0xc7
> > [ 6709.484099]  [<ffffffff81134efa>] ? __pollwait+0xc7/0xc7
> > [ 6709.484107]  [<ffffffff81134efa>] ? __pollwait+0xc7/0xc7
> > [ 6709.484118]  [<ffffffff8112fde0>] ? putname+0x2d/0x36
> > [ 6709.484127]  [<ffffffff8112fde0>] ? putname+0x2d/0x36
> > [ 6709.484138]  [<ffffffff81045cb7>] ? timespec_add_safe+0x32/0x5f
> > [ 6709.484146]  [<ffffffff81018078>] ? read_tsc+0x9/0x1b
> > [ 6709.484155]  [<ffffffff8113509a>] ? poll_select_set_timeout+0x61/0x75
> > [ 6709.484163]  [<ffffffff811360d8>] sys_poll+0x4e/0xb7
> > [ 6709.484173]  [<ffffffff81552896>] sysenter_dispatch+0x7/0x21
> > 
> 
> Hmm, this can also be reported if you have an rcu leak. Which would also
> explain your memory leak. RCU is the kernel's "garbage collector" and if
> it gets stuck, then you will definitely start seeing memory leaks, as
> memory wont be freed.

If RCU is stuck, you should see RCU CPU stall warnings, which can
give clues as to what is causing RCU to get stuck.

> Paul, know of any fixes in RCU that could have caused this?
> 
> -- Steve
> 
> > The taint is due to nouveau. I am sure that this
> > "sleeping-in-invalid-context" report is a consequence of the memory leak
> > that I could not convert into something reportable. But still, it is
> > something that the kernel wants me to report, that's why this e-mail.
> > 
> > The kernel is configured as CONFIG_PREEMPT=y, if this is relevant.

Could you please send along your full .config?

							Thanx, Paul