Sometimes a "BUG: sleeping function called from invalid context" message is not indicative of locking problems, but is the result of a stack overflow corrupting the thread info.
Witness http://oss.sgi.com/archives/xfs/2014-02/msg00325.html for example, which took a few go-rounds to sort out. If we're printing the warning, things are wonky already, and it'd be informative to check for the stack end corruption at this point, too. Signed-off-by: Eric Sandeen <sand...@redhat.com> --- diff --git a/kernel/sched/core.c b/kernel/sched/core.c index b5797b7..4ef726c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7328,6 +7328,9 @@ void ___might_sleep(const char *file, int line, int preempt_offset) in_atomic(), irqs_disabled(), current->pid, current->comm); + if (task_stack_end_corrupted(current)) + printk(KERN_EMERG "Thread overran stack, or stack corrupted\n"); + debug_show_held_locks(current); if (irqs_disabled()) print_irqtrace_events(current); -- 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/
