On Thu, Oct 11, 2012 at 09:59:16AM +0900, Greg Kroah-Hartman wrote: > 3.4-stable review patch. If anyone has any objections, please let me know. > > ------------------ > > From: Michael Wang <wang...@linux.vnet.ibm.com> > > commit 947ca1856a7e60aa6d20536785e6a42dff25aa6e upstream. > > DEADLOCK will be report while running a kernel with NUMA and LOCKDEP enabled, > the process of this fake report is: > > kmem_cache_free() //free obj in cachep > -> cache_free_alien() //acquire cachep's l3 alien lock > -> __drain_alien_cache() > -> free_block() > -> slab_destroy() > -> kmem_cache_free() //free slab in cachep->slabp_cache > -> cache_free_alien() //acquire cachep->slabp_cache's l3 alien lock > > Since the cachep and cachep->slabp_cache's l3 alien are in the same lock > class, > fake report generated. > > This should not happen since we already have init_lock_keys() which will > reassign the lock class for both l3 list and l3 alien. > > However, init_lock_keys() was invoked at a wrong position which is before we > invoke enable_cpucache() on each cache. > > Since until set slab_state to be FULL, we won't invoke enable_cpucache() > on caches to build their l3 alien while creating them, so although we invoked > init_lock_keys(), the l3 alien lock class won't change since we don't have > them until invoked enable_cpucache() later. > > This patch will invoke init_lock_keys() after we done enable_cpucache() > instead of before to avoid the fake DEADLOCK report. > > Michael traced the problem back to a commit in release 3.0.0:
I don't see this fix in the last 3.0 stable release. Shouldn't it go there too? -- Steve > > commit 30765b92ada267c5395fc788623cb15233276f5c > Author: Peter Zijlstra <pet...@infradead.org> > Date: Thu Jul 28 23:22:56 2011 +0200 > > slab, lockdep: Annotate the locks before using them > > Fernando found we hit the regular OFF_SLAB 'recursion' before we > annotate the locks, cure this. > > The relevant portion of the stack-trace: > > > [ 0.000000] [<c085e24f>] rt_spin_lock+0x50/0x56 > > [ 0.000000] [<c04fb406>] __cache_free+0x43/0xc3 > > [ 0.000000] [<c04fb23f>] kmem_cache_free+0x6c/0xdc > > [ 0.000000] [<c04fb2fe>] slab_destroy+0x4f/0x53 > > [ 0.000000] [<c04fb396>] free_block+0x94/0xc1 > > [ 0.000000] [<c04fc551>] do_tune_cpucache+0x10b/0x2bb > > [ 0.000000] [<c04fc8dc>] enable_cpucache+0x7b/0xa7 > > [ 0.000000] [<c0bd9d3c>] kmem_cache_init_late+0x1f/0x61 > > [ 0.000000] [<c0bba687>] start_kernel+0x24c/0x363 > > [ 0.000000] [<c0bba0ba>] i386_start_kernel+0xa9/0xaf > > Reported-by: Fernando Lopez-Lezcano <na...@ccrma.stanford.edu> > Acked-by: Pekka Enberg <penb...@kernel.org> > Signed-off-by: Peter Zijlstra <a.p.zijls...@chello.nl> > Link: http://lkml.kernel.org/r/1311888176.2617.379.camel@laptop > Signed-off-by: Ingo Molnar <mi...@elte.hu> > > The commit moved init_lock_keys() before we build up the alien, so we > failed to reclass it. > > Acked-by: Christoph Lameter <c...@linux.com> > Tested-by: Paul E. McKenney <paul...@linux.vnet.ibm.com> > Signed-off-by: Michael Wang <wang...@linux.vnet.ibm.com> > Signed-off-by: Pekka Enberg <penb...@kernel.org> > Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> > > --- > mm/slab.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > --- a/mm/slab.c > +++ b/mm/slab.c > @@ -1685,9 +1685,6 @@ void __init kmem_cache_init_late(void) > > g_cpucache_up = LATE; > > - /* Annotate slab for lockdep -- annotate the malloc caches */ > - init_lock_keys(); > - > /* 6) resize the head arrays to their final sizes */ > mutex_lock(&cache_chain_mutex); > list_for_each_entry(cachep, &cache_chain, next) > @@ -1695,6 +1692,9 @@ void __init kmem_cache_init_late(void) > BUG(); > mutex_unlock(&cache_chain_mutex); > > + /* Annotate slab for lockdep -- annotate the malloc caches */ > + init_lock_keys(); > + > /* Done! */ > g_cpucache_up = FULL; > > > > -- > 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/ -- 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/
