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Message-ID: <1357163686.3652.46.camel@bwh-desktop.uk.solarflarecom.com>
Subject: Re: [PATCH v4] lib: cpu_rmap: avoid flushing all workqueues
From: Ben Hutchings <bhutchings@solarflare.com>
To: David Decotigny <decot@googlers.com>
CC: <linux-kernel@vger.kernel.org>, "David S. Miller" <davem@davemloft.net>,
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Date: Wed, 2 Jan 2013 21:54:46 +0000
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On Wed, 2013-01-02 at 13:52 -0800, David Decotigny wrote:
> In some cases, free_irq_cpu_rmap() is called while holding a lock
> (eg. rtnl). This can lead to deadlocks, because it invokes
> flush_scheduled_work() which ends up waiting for whole system
> workqueue to flush, but some pending works might try to acquire the
> lock we are already holding.
> 
> This commit uses reference-counting to replace
> irq_run_affinity_notifiers(). It also removes
> irq_run_affinity_notifiers() altogether.
> 
> Signed-off-by: David Decotigny <decot@googlers.com>
[...]

Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>

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