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Re: [Xen-devel] [PATCHv3] QEMU(upstream): Disable xen's use of O_DIRECT by default as it results in crashes.

On Mon, Mar 11, 2013 at 02:42:21PM +0000, George Dunlap wrote:
> On 11/03/13 14:02, Alex Bligh wrote:
> >
> >--On 8 March 2013 12:54:16 +0000 George Dunlap
> ><George.Dunlap@xxxxxxxxxxxxx> wrote:
> >
> >>On Fri, Mar 8, 2013 at 11:40 AM, Alex Bligh <alex@xxxxxxxxxxx> wrote:
> >>>Due to what is almost certainly a kernel bug, writes with
> >>>O_DIRECT may continue to reference the page after the write
> >>>has been marked as completed, particularly in the case of
> >>>TCP retransmit. In other scenarios, this "merely" risks
> >>>data corruption on the write, but with Xen pages from domU
> >>>are only transiently mapped into dom0's memory, resulting
> >>>in kernel panics when they are subsequently accessed.
> >>>
> >>>This brings PV devices in line with emulated devices. Removing
> >>>O_DIRECT is safe as barrier operations are now correctly passed
> >>>through.
> >>Not qualified to comment on the technical merits of the patch, but re
> >>the commit message:
> >>
> >>Acked-by: George Dunlap <george.dunlap@xxxxxxxxxxxxx>
> >Any further thoughts on this one?
> I believe that Stefano is the person to commit it, but he's on
> holiday for two weeks.

Who is his backup?
>  -George

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