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From: Rik van Riel <riel@redhat.com>
To: nick <xerofoify@gmail.com>, Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm:Avoid soft lockup due to possible attempt of double locking object's lock in __delete_object
Date: Tue, 06 Sep 2016 20:45:19 -0400	[thread overview]
Message-ID: <1473209119.32433.174.camel@redhat.com> (raw)
In-Reply-To: <e2e8b8fc-3deb-aa23-c54e-43f12dd0a941@gmail.com>

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On Wed, 2016-08-31 at 09:24 -0400, nick wrote:
> 
> On 2016-08-31 03:54 AM, Catalin Marinas wrote:
> > On Tue, Aug 30, 2016 at 02:35:12PM -0400, Nicholas Krause wrote:
> > > This fixes a issue in the current locking logic of the function,
> > > __delete_object where we are trying to attempt to lock the passed
> > > object structure's spinlock again after being previously held
> > > elsewhere by the kmemleak code. Fix this by instead of assuming
> > > we are the only one contending for the object's lock their are
> > > possible other users and create two branches, one where we get
> > > the lock when calling spin_trylock_irqsave on the object's lock
> > > and the other when the lock is held else where by kmemleak.
> > 
> > Have you actually got a deadlock that requires this fix?
> > 
> Yes I have got a deadlock that this does fix.

Why don't you share the backtrace with us?

Claiming you have a deadlock, but not sharing
it on the list means nobody can see what the
problem is you are trying to address.

It would be good if every email with a patch
that you post starts with an actual detailed
problem description.

Can you do that?

-- 

All Rights Reversed.

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  reply	other threads:[~2016-09-07  0:45 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-08-30 18:35 [PATCH] mm:Avoid soft lockup due to possible attempt of double locking object's lock in __delete_object Nicholas Krause
2016-08-31  7:54 ` Catalin Marinas
2016-08-31 13:24   ` nick
2016-09-07  0:45     ` Rik van Riel [this message]
2016-08-31 13:41   ` nick
2016-08-31 14:35     ` Catalin Marinas
2016-08-31 21:08   ` Valdis.Kletnieks
2016-08-31 21:28     ` nick
2016-09-07  0:51       ` Rik van Riel
2016-09-07  1:12         ` nick
2016-09-07  1:22           ` Rik van Riel

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