From: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
To: Qing Huang <qing.huang@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Grant Likely <grant.likely@linaro.org>,
Santosh Shilimkar <santosh.shilimkar@oracle.com>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] device probe: add self triggered delayed work request
Date: Tue, 9 Aug 2016 13:11:22 +0300 [thread overview]
Message-ID: <20160809101122.GA30759@shamir-linux.uk.oracle.com> (raw)
In-Reply-To: <57A91F5D.1060605@oracle.com>
On Mon, Aug 08, 2016 at 05:10:05PM -0700, Qing Huang wrote:
>
> Not sure if I understood your scenario. Why there is a deadlock here?
>
CPU0 | CPU1
---------------------------------------------------------------------------------------------
driver_deferred_probe_add | driver_deferred_probe_trigger_wrapper
mutex_lock(&deferred_probe_mutex) | driver_deferred_probe_trigger
cancel_delayed_work(&deferred_probe_trigger_work) | mutex_lock(&deferred_probe_mutex)
wait for "driver_deferred_probe_trigger_wrapper" | wait for "deferred_probe_mutex"
is this possible scenario with this patch?
if yes then CPU0 will wait for CPU1 to finish the delayed work whith
mutex deferred_probe_mutex held while CPU1 will try to finish the
delayed work and will wait for the same mutex forever.
it seems like dead lock scenario to me.
please say if this scenario is possible.
BR, Shamir Rabinovitch
next prev parent reply other threads:[~2016-08-09 10:11 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-08 10:42 [PATCH] device probe: add self triggered delayed work request Shamir Rabinovitch
2016-08-09 0:10 ` Qing Huang
2016-08-09 10:11 ` Shamir Rabinovitch [this message]
2016-08-09 20:57 ` Qing Huang
-- strict thread matches above, loose matches on Subject: below --
2016-07-30 5:39 Qing Huang
2016-08-08 20:44 ` Frank Rowand
2016-08-08 21:51 ` Qing Huang
2016-08-09 1:11 ` Frank Rowand
2016-08-09 1:15 ` Santosh Shilimkar
2016-08-09 7:16 ` Frank Rowand
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