On Mon, Aug 22, 2016 at 07:24:07PM -0400, Brijesh Singh wrote:

From: Tom Lendacky <thomas.lendacky@amd.com>

When a guest causes a NPF which requires emulation, KVM sometimes walks
the guest page tables to translate the GVA to a GPA. This is unnecessary
most of the time on AMD hardware since the hardware provides the GPA in
EXITINFO2.

The only exception cases involve string operations involving rep or
operations that use two memory locations. With rep, the GPA will only be
the value of the initial NPF and with dual memory locations we won't know
which memory address was translated into EXITINFO2.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/kvm_emulate.h |    3 +++
 arch/x86/include/asm/kvm_host.h    |    3 +++
 arch/x86/kvm/svm.c                 |    2 ++
 arch/x86/kvm/x86.c                 |   17 ++++++++++++++++-
 4 files changed, 24 insertions(+), 1 deletion(-)

FWIW, LGTM. (Gotta love replying in acronyms :-))

Reviewed-by: Borislav Petkov <redacted>

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix ImendA?rffer, Jane Smithard, Graham Norton, HRB 21284 (AG NA 1/4 rnberg)
-- 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>