From: Andi Kleen <andi@firstfloor.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>,
roger.larsson@e-gatan.se, linux-kernel@vger.kernel.org,
mingo@elte.hu, rml@tech9.net, pavel@ucw.cz,
netdev@vger.kernel.org
Subject: Re: PROBLEM: in_atomic() misuse all over the place
Date: Sat, 31 Jan 2009 06:55:08 +0100 [thread overview]
Message-ID: <20090131055508.GD18453@one.firstfloor.org> (raw)
In-Reply-To: <20090130160316.7e53ef99.akpm@linux-foundation.org>
> There's a bit of a problem here. If someone accidentally uses
> gfp_any() inside a spinlock, it will do a sleeping allocation on
> non-preempt kernels and will do an atomic allocation on preemptible
> kernels, so we won't get to see the warning which would allow us to fix
> the bug.
Yes exporting the function to drivers is dangerous I agree because
it's easy to abuse.
> Would using irq_count() work? If so, that would fix this up.
There's nothing that works reliably to detect spinlocks on non
preempt kernels.
-Andi
--
ak@linux.intel.com -- Speaking for myself only.
next prev parent reply other threads:[~2009-01-31 5:39 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-27 23:10 PROBLEM: in_atomic() misuse all over the place Roger Larsson
2009-01-28 0:12 ` Robert Hancock
2009-01-31 11:45 ` Joerg Roedel
2009-01-28 12:18 ` Andi Kleen
2009-01-31 0:03 ` Andrew Morton
2009-01-31 5:55 ` Andi Kleen [this message]
2009-01-31 5:49 ` Andrew Morton
2009-01-31 8:48 ` David Miller
2009-01-31 8:58 ` Andrew Morton
2009-02-04 16:17 ` Pavel Machek
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