[3.13.y.z extended stable] Patch "KVM: x86: Emulator does not decode clflush well" has been added to staging queue

[Kamal Mostafa]

On Tue, 2014-11-04 at 10:56 +0100, Paolo Bonzini wrote:
> >> From 3cf1cc997f89242c852dca2469ca4303348d29a5 Mon Sep 17 00:00:00 2001
> >> From: Nadav Amit <namit at cs.technion.ac.il>
> >> Date: Mon, 13 Oct 2014 13:04:13 +0300
> >> Subject: KVM: x86: Emulator does not decode clflush well
> >>
> >> commit 13e457e0eebf0a0c82c38ceb890d93eb826d62a6 upstream.
> >>
> >> Currently, all group15 instructions are decoded as clflush (e.g., mfence,
> >> xsave).  In addition, the clflush instruction requires no prefix (66/f2/f3)
> >> would exist. If prefix exists it may encode a different instruction (e.g.,
> >> clflushopt).
> >>
> >> Creating a group for clflush, and different group for each prefix.
> >>
> >> This has been the case forever, but the next patch needs the cflush group
> >> in order to fix a bug introduced in 3.17.
> > 
> > Given the above ^^^
> > 
> >> Fixes: 41061cdb98a0bec464278b4db8e894a3121671f5
> > 
> > And the fact that this commit isn't present in 3.13, I'm not sure this
> > patch is relevant for this stable kernel.  Could someone confirm this
> > please?
> 
> Yes, indeed I thought the "Fixes:" header was also used to find which
> commits should go in which stable kernel.

My (mis-)reading of this one led me to think it was fixing an additional
useful thing, in addition to the bug introduced in 3.17.  I'll drop it
from the 3.13-stable queue.

Thanks for the correction Luis, Nadav, and Paolo!

 -Kamal