From: "Brandeburg, Jesse" <jesse.brandeburg@intel.com>
To: Matthew Wilcox <matthew@wil.cx>, Ingo Molnar <mingo@elte.hu>,
       Thomas Gleixner <tglx@linutronix.de>,
       Linus Torvalds <torvalds@osdl.org>
CC: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@osdl.org>, Yinghai Lu <yhlu.kernel@gmail.com>
Date: Fri, 21 Nov 2008 10:31:59 -0800
Subject: RE: [PATCH] x86: Fix interrupt leak due to migration
Thread-Topic: [PATCH] x86: Fix interrupt leak due to migration
Thread-Index: AclLVq48YYkR2c1US1mBi/iiNwjw5QAsHeiQ
Message-ID: <F169D4F5E1F1974DBFAFABF47F60C10A0EC28107@orsmsx507.amr.corp.intel.com>
References: <20081120210932.GW1617@parisc-linux.org>
In-Reply-To: <20081120210932.GW1617@parisc-linux.org>
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Matthew Wilcox wrote:
> When we migrate an interrupt from one CPU to another, we set the
> move_in_progress flag and clean up the vectors later once they're not
> being used.  If you're unlucky and call destroy_irq() before the
> vectors become un-used, the move_in_progress flag is never cleared,
> which causes the interrupt to become unusable.
> 
> This was discovered by Jesse Brandeburg for whom it manifested as an
> MSI-X device refusing to use MSI-X mode when the driver was unloaded
> and reloaded repeatedly.
> 
> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>

We did some other quick testing on this and it seems good.  Thanks 
and good work Matthew!

Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
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