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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 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>


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