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From: Wei Liu <wei.liu2@citrix.com>
To: David Vrabel <david.vrabel@citrix.com>
Cc: <netdev@vger.kernel.org>, <xen-devel@lists.xenproject.org>,
	Ian Campbell <ian.campbell@citrix.com>,
	Wei Liu <wei.liu2@citrix.com>
Subject: Re: [PATCHv1 net] xen-netback: release pending index before pushing Tx responses
Date: Tue, 24 Feb 2015 12:03:24 +0000	[thread overview]
Message-ID: <20150224120324.GH20083@zion.uk.xensource.com> (raw)
In-Reply-To: <1424776679-7509-1-git-send-email-david.vrabel@citrix.com>

On Tue, Feb 24, 2015 at 11:17:59AM +0000, David Vrabel wrote:
> If the pending indexes are released /after/ pushing the Tx response
> then a stale pending index may be used if a new Tx request is
> immediately pushed by the frontend.  The may cause various WARNINGs or
> BUGs if the stale pending index is actually still in use.
> 
> Fix this by releasing the pending index before pushing the Tx
> response.
> 
> The full barrier for the pending ring update is not required since the
> the Tx response push already has a suitable write barrier.
> 
> Signed-off-by: David Vrabel <david.vrabel@citrix.com>

Reviewed-by: Wei Liu <wei.liu2@citrix.com>

  reply	other threads:[~2015-02-24 12:03 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-02-24 11:17 [PATCHv1 net] xen-netback: release pending index before pushing Tx responses David Vrabel
2015-02-24 12:03 ` Wei Liu [this message]
2015-02-24 21:24 ` David Miller

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