On Tue, Jan 09, 2007 at 05:57:40PM +0530, Srivatsa Vaddagiri wrote: > On Tue, Jan 09, 2007 at 01:17:38PM +0100, Heiko Carstens wrote: > > missing in kernel cpu.c in _cpu_down() in case CPU_DOWN_PREPARE > > returned with NOTIFY_BAD. However... this reveals that there is just a > > more fundamental problem. > > > > The workqueue code grabs a lock on CPU_[UP|DOWN]_PREPARE and releases it > > again on CPU_DOWN_FAILED/CPU_UP_CANCELED. If something in the callchain > > returns NOTIFY_BAD the rest of the entries in the callchain won't be > > called anymore. But DOWN_FAILED/UP_CANCELED will be called for every > > entry. > > So we might even end up with a mutex_unlock(&workqueue_mutex) even if > > mutex_lock(&workqueue_mutex) hasn't been called... > > This is a known problem. Gautham had sent out patches to address them > > http://lkml.org/lkml/2006/11/14/93 > > Looks like they are in latest mm tree. Perhaps the testcase should be > retried against latest mm.
Ah, nice! Wasn't aware of that. But I still think we should have a CPU_DOWN_FAILED in case CPU_DOWN_PREPARED failed. Also the slab cache code hasn't been changed to make use of the of the new CPU_LOCK_[ACQUIRE|RELEASE] stuff. I'm going to send patches in reply to this mail. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
