From: Mark Lord <lkml@rtr.ca>
To: James Bottomley <James.Bottomley@SteelEye.com>
Cc: Christoph Hellwig <hch@infradead.org>,
Jeff Garzik <jgarzik@pobox.com>, Mark Lord <lsml@rtr.ca>,
Linux Kernel <linux-kernel@vger.kernel.org>,
SCSI Mailing List <linux-scsi@vger.kernel.org>
Subject: Re: [PATCH] QStor SATA/RAID driver for 2.6.9-rc3
Date: Tue, 12 Oct 2004 12:59:01 -0400 [thread overview]
Message-ID: <416C0D55.1020603@rtr.ca> (raw)
In-Reply-To: <1097250465.2412.49.camel@mulgrave>
James Bottomley wrote:
> On Fri, 2004-10-08 at 10:38, Mark Lord wrote:
>
>>Can deadlock occur here, since qstor.c is already using schedule_work()
>>as part of it's internal bottom-half handling for abnormal conditions?
>>
>>Eg. hotplug event -> schedule_work -> mid-layer -> queuecommand
>> --> sleep :: interrupt -> schedule_work -> deadlock?
>>
>
>
> Since you wouldn't go straight from schedule_work->mid-layer, I assume
> you mean that when the workqueue thread runs the work?
Yes. The workqueue thread will invoke the mid-layer function,
which will do a queuecommand, which will return to the mid-layer,
which will then SLEEP waiting for the command to complete,
which will sleep that workqueue thread.
As part of the interrupt processing to complete the command in the LLD,
it is possible that schedule_work may be necessary, requiring that
a workqueue thread be run. If this means the same thread that is
already sleeping courtesy of the mid-layer, then we could have a problem.
Comments?
--
Mark Lord
(hdparm keeper & the original "Linux IDE Guy")
next prev parent reply other threads:[~2004-10-12 17:00 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-10-04 19:11 [PATCH] QStor SATA/RAID driver for 2.6.9-rc3 Mark Lord
2004-10-07 13:42 ` Mark Lord
2004-10-07 14:07 ` Christoph Hellwig
2004-10-07 15:35 ` Mark Lord
2004-10-07 15:50 ` Jeff Garzik
2004-10-07 20:17 ` Mark Lord
2004-10-07 20:30 ` Jeff Garzik
2004-10-07 20:34 ` Mark Lord
2004-10-07 20:46 ` Jeff Garzik
2004-10-07 20:54 ` Mark Lord
2004-10-07 21:15 ` Christoph Hellwig
2004-10-07 22:03 ` Mark Lord
2004-10-20 15:44 ` Christoph Hellwig
2004-10-07 23:39 ` PATCH] " Mark Lord
2004-10-13 18:56 ` [PATCH] QStor SATA/RAID driver for 2.6.9-rc4 Mark Lord
2004-10-08 13:19 ` [PATCH] QStor SATA/RAID driver for 2.6.9-rc3 James Bottomley
2004-10-08 15:15 ` Mark Lord
2004-10-08 15:27 ` James Bottomley
2004-10-08 15:34 ` Mark Lord
2004-10-08 15:38 ` Jeff Garzik
2004-10-08 16:01 ` James Bottomley
2004-10-12 17:00 ` Mark Lord
2004-10-12 17:05 ` Jeff Garzik
2004-10-12 17:09 ` James Bottomley
2004-10-12 17:31 ` Jeff Garzik
2004-10-08 15:38 ` Mark Lord
2004-10-08 15:47 ` James Bottomley
2004-10-08 15:49 ` Jeff Garzik
2004-10-12 16:59 ` Mark Lord [this message]
2004-10-12 17:03 ` Jeff Garzik
2004-10-12 17:14 ` Mark Lord
2004-10-12 17:19 ` Jeff Garzik
2004-10-12 17:23 ` Jeff Garzik
2004-10-12 17:17 ` James Bottomley
2004-10-12 17:22 ` Mark Lord
2004-10-12 17:30 ` James Bottomley
2004-10-12 17:33 ` Mark Lord
2004-10-12 17:42 ` Jeff Garzik
2004-10-12 17:51 ` Mark Lord
2004-10-12 18:12 ` James Bottomley
2004-10-12 18:36 ` Mark Lord
2004-10-12 18:25 ` driver hacking tips (was Re: [PATCH] QStor SATA/RAID driver for 2.6.9-rc3) Jeff Garzik
2004-10-12 19:18 ` Mark Lord
2004-10-12 19:40 ` Jeff Garzik
2004-10-12 17:34 ` [PATCH] QStor SATA/RAID driver for 2.6.9-rc3 Jeff Garzik
2004-10-07 20:31 ` Christoph Hellwig
2004-10-07 20:35 ` Jeff Garzik
2004-10-07 21:16 ` Mark Lord
2004-10-07 21:44 ` Jeff Garzik
2004-10-07 21:45 ` Jeff Garzik
2004-10-13 20:04 ` Jeff Garzik
2004-10-13 22:16 ` Mark Lord
2004-10-13 22:41 ` Jeff Garzik
2004-10-13 23:24 ` Mark Lord
2004-10-13 23:39 ` Jeff Garzik
2004-10-14 16:30 ` Mark Lord
2004-10-14 16:37 ` Mark Lord
2004-10-14 16:52 ` [PATCH] Export ata_scsi_simulate() for use by non-libata drivers Mark Lord
2004-10-14 17:04 ` Jeff Garzik
2004-10-14 18:44 ` Mark Lord
2004-10-15 5:04 ` Jeff Garzik
2004-10-15 13:25 ` John W. Linville
2004-10-15 14:59 ` Randy.Dunlap
2004-10-15 15:38 ` Jeff Garzik
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