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From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: catalin.marinas@arm.com, linux-kernel@vger.kernel.org
Subject: Re: [2.6.32-rc3 kmemleak] WARNING: at kernel/lockdep.c:3161 check_flags+0xbe/0x180()
Date: Wed, 7 Oct 2009 08:51:42 -0700	[thread overview]
Message-ID: <20091007155142.GB6743@linux.vnet.ibm.com> (raw)
In-Reply-To: <200910050315.n953FCD9030264@www262.sakura.ne.jp>

On Mon, Oct 05, 2009 at 12:15:12PM +0900, Tetsuo Handa wrote:
> Hello.
> 
> I got this error.
> 
> [    0.000000] Linux version 2.6.32-rc3 (root@tomoyo) (gcc version 3.3.5 (Debian 1:3.3.5-13)) #1 SMP Mon Oct 5 11:24:05 JST 2009
> (...snipped...)
> [    0.000000] -------------------------------------------------------
> [    0.000000] Good, all 218 testcases passed! |
> [    0.000000] ---------------------------------
> [    0.000000] ------------[ cut here ]------------
> [    0.000000] WARNING: at kernel/lockdep.c:3161 check_flags+0xbe/0x180()
> [    0.000000] Hardware name: VMware Virtual Platform
> [    0.000000] Modules linked in:
> [    0.000000] Pid: 0, comm: swapper Not tainted 2.6.32-rc3 #1
> [    0.000000] Call Trace:
> [    0.000000]  [<c104182d>] ? printk+0x1d/0x30
> [    0.000000]  [<c107069e>] ? check_flags+0xbe/0x180
> [    0.000000]  [<c1040de1>] warn_slowpath_common+0x81/0xa0
> [    0.000000]  [<c107069e>] ? check_flags+0xbe/0x180
> [    0.000000]  [<c1040e5a>] warn_slowpath_null+0x1a/0x30
> [    0.000000]  [<c107069e>] check_flags+0xbe/0x180
> [    0.000000]  [<c106e52e>] lockdep_trace_alloc+0x2e/0x60
> [    0.000000]  [<c10cfedd>] kmem_cache_alloc+0x2d/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c106e22b>] ? trace_hardirqs_on+0xb/0x10
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cf9c4>] ? cache_alloc_refill+0x144/0x210
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cef9f>] alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10cf3de>] cache_grow+0xae/0x170
> [    0.000000]  [<c10cf9fb>] cache_alloc_refill+0x17b/0x210
> [    0.000000]  [<c10d005a>] kmem_cache_alloc+0x1aa/0x1d0
> [    0.000000]  [<c10cd9b8>] ? obj_size+0x8/0x10
> [    0.000000]  [<c10d3969>] ? create_object+0x29/0x220
> [    0.000000]  [<c10d3969>] create_object+0x29/0x220
> [    0.000000]  [<c10cd9a8>] ? obj_offset+0x8/0x10
> [    0.000000]  [<c10ce07a>] ? poison_obj+0x2a/0x50
> [    0.000000]  [<c1321693>] kmemleak_alloc+0x83/0xd0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  [<c10d0035>] kmem_cache_alloc+0x185/0x1d0
> [    0.000000]  [<c106e1b7>] ? trace_hardirqs_on_caller+0xf7/0x160
> [    0.000000]  [<c10cef9f>] ? alloc_slabmgmt+0x5f/0x80
> [    0.000000]  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>  <IRQ>(...snipped...)
> 
> Adding kmemleak=off to kernel command line solves this error.
> Config is at http://I-love.SAKURA.ne.jp/tmp/config-2.6.32-rc3
> 
> By the way,
> > static void early_alloc(struct early_log *log)
> > {
> >         struct kmemleak_object *object;
> >         unsigned long flags;
> >         int i;
> > 
> >         if (!atomic_read(&kmemleak_enabled) || !log->ptr || IS_ERR(log->ptr))
> >                 return;
> > 
> >         /*
> >          * RCU locking needed to ensure object is not freed via put_object().
> >          */
> >         rcu_read_lock();
> >         object = create_object((unsigned long)log->ptr, log->size,
> >                                log->min_count, GFP_KERNEL);
> I think we can't use GFP_KERNEL inside rcu_read_lock()...
> >         spin_lock_irqsave(&object->lock, flags);
> >         for (i = 0; i < log->trace_len; i++)
> >                 object->trace[i] = log->trace[i];
> >         object->trace_len = log->trace_len;
> >         spin_unlock_irqrestore(&object->lock, flags);
> >         rcu_read_unlock();
> > }
> 
> [PATCH 2.6.32-rc3] kmemleak: Use GFP_ATOMIC for early_alloc().
> 
> We can't use GFP_KERNEL inside rcu_read_lock().
> 
> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> ---
>  mm/kmemleak.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> --- linux-2.6.32-rc3.orig/mm/kmemleak.c
> +++ linux-2.6.32-rc3/mm/kmemleak.c
> @@ -833,7 +833,7 @@ static void early_alloc(struct early_log
>  	 */
>  	rcu_read_lock();
>  	object = create_object((unsigned long)log->ptr, log->size,
> -			       log->min_count, GFP_KERNEL);
> +			       log->min_count, GFP_ATOMIC);

Won't we need to check for object==NULL?

							Thanx, Paul

>  	spin_lock_irqsave(&object->lock, flags);
>  	for (i = 0; i < log->trace_len; i++)
>  		object->trace[i] = log->trace[i];
> 
> Regards.
> --
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  parent reply	other threads:[~2009-10-07 15:52 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-05  3:15 [2.6.32-rc3 kmemleak] WARNING: at kernel/lockdep.c:3161 check_flags+0xbe/0x180() Tetsuo Handa
2009-10-05  8:55 ` Catalin Marinas
2009-10-07 15:51 ` Paul E. McKenney [this message]
2009-10-08 12:34   ` [2.6.32-rc3 kmemleak] WARNING: at kernel/lockdep.c:3161check_flags+0xbe/0x180() Tetsuo Handa
2009-10-08 12:42     ` Catalin Marinas
2009-10-13  3:17       ` Tetsuo Handa
2009-10-13 12:00         ` Catalin Marinas
2009-10-13 12:57           ` [2.6.32-rc3 kmemleak] WARNING: at kernel/lockdep.c:3161 check_flags+0xbe/0x180() Tetsuo Handa
2009-10-13 15:25           ` [2.6.32-rc3 kmemleak] WARNING: atkernel/lockdep.c:3161check_flags+0xbe/0x180() Tetsuo Handa
2009-10-14 11:55             ` Tetsuo Handa
2009-10-14 12:22               ` Catalin Marinas
2009-10-14 13:12                 ` [2.6.32-rc3 kmemleak] WARNING:atkernel/lockdep.c:3161check_flags+0xbe/0x180() Tetsuo Handa
2009-10-14 14:55                   ` Catalin Marinas
2009-10-14 21:50                     ` [2.6.32-rc3 kmemleak] WARNING: at kernel/lockdep.c:3161 check_flags+0xbe/0x180() Tetsuo Handa
2009-10-15  3:52                     ` Tetsuo Handa
2009-10-15  8:45                       ` Catalin Marinas
2009-10-08 12:39   ` Catalin Marinas

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