On Wed, Feb 12, 2014 at 05:10:38PM +1100, Dave Chinner wrote: > On Wed, Feb 12, 2014 at 12:50:27AM -0500, Dave Jones wrote: > > On Wed, Feb 12, 2014 at 04:40:43PM +1100, Dave Chinner wrote: > > > > > None of the XFS code disables interrupts in that path, not does is > > > call outside XFS except to dispatch IO. The stack is pretty deep at > > > this point and I know that the standard (non stacked) IO stack can > > > consume >3kb of stack space when it gets down to having to do memory > > > reclaim during GFP_NOIO allocation at the lowest level of SCSI > > > drivers. Stack overruns typically show up with symptoms like we are > > > seeing. > > > .. > > > > > > Dave, before chasing ghosts, can you (like Eric originally asked) > > > turn on stack overrun detection? > > > > CONFIG_DEBUG_STACKOVERFLOW ? Already turned on. > > That only checks stack usage when an interrupt is taken. If no > interrupts are taken when stack usage is within 128 bytes of > overflow, then it doesn't catch it. > > I tend to use CONFIG_DEBUG_STACK_USAGE=y as it records the maximum > stack usage of a process via canary overwrites and it records it in > do_exit().
I had that on too. The only message from it came from quite a while before the trace that happened overnight.. [ 3415.655125] trinity-c0 (4383) used greatest stack depth: 992 bytes left [12900.804230] BUG: sleeping function called from invalid context at mm/mempool.c:203 > I also use the stack tracer to record the largest stack > usage seen so I know exactly what code paths are approaching stack > overruns... I can give that a try later. Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/