From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gal Rosen <galr@storwize.com>
Subject: Re: [PATCH] qla2xxx: Fix dpc_thread race on the module unload
Date: Thu, 31 Jul 2008 09:12:23 +0300
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To: Vladislav Bolkhovitin <vst@vlnb.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>, linux-driver@qlogic.com, linux-scsi@vger.kernel.org, scst-devel@lists.sourceforge.net

Andrew,

Add checking of the flag online still does not answer the race that Vlad
stated before, unless you thought about another way without lock to
protect this thread.

> Nope, taking only one that hunk from this patch isn't sufficient.
> Around 
> dpc_thread there is pretty simple and classical race. You can't do
> 
> if (x != NULL)
> y = *x;
> 
> without any protection, if x can be set to NULL by another thread. It 
> can happen exactly between "if" and "*x" and hence lead to a crash,
> correct?

Gal.