|
 |
c11cae |
From 6fff75c304d9403ac7c36c436ddf53497f6417ef Mon Sep 17 00:00:00 2001
|
|
|
c11cae |
Message-Id: <6fff75c304d9403ac7c36c436ddf53497f6417ef@dist-git>
|
|
|
c11cae |
From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= <berrange@redhat.com>
|
|
|
c11cae |
Date: Mon, 21 May 2018 23:05:08 +0100
|
|
|
c11cae |
Subject: [PATCH] cpu: define the 'virt-ssbd' CPUID feature bit (CVE-2018-3639)
|
|
|
c11cae |
MIME-Version: 1.0
|
|
|
c11cae |
Content-Type: text/plain; charset=UTF-8
|
|
|
c11cae |
Content-Transfer-Encoding: 8bit
|
|
|
c11cae |
|
|
|
c11cae |
Some AMD processors only support a non-architectural means of
|
|
|
c11cae |
enabling Speculative Store Bypass Disable. To allow simplified
|
|
|
c11cae |
handling in virtual environments, hypervisors will expose an
|
|
|
c11cae |
architectural definition through CPUID bit 0x80000008_EBX[25].
|
|
|
c11cae |
This needs to be exposed to guest OS running on AMD x86 hosts to
|
|
|
c11cae |
allow them to protect against CVE-2018-3639.
|
|
|
c11cae |
|
|
|
c11cae |
Note that since this CPUID bit won't be present in the host CPUID
|
|
|
c11cae |
results on physical hosts, it will not be enabled automatically
|
|
|
c11cae |
in guests configured with "host-model" CPU unless using QEMU
|
|
|
c11cae |
version >= 2.9.0. Thus for older versions of QEMU, this feature
|
|
|
c11cae |
must be manually enabled using policy=force. Guests using the
|
|
|
c11cae |
"host-passthrough" CPU mode do not need special handling.
|
|
|
c11cae |
|
|
|
c11cae |
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
|
|
|
c11cae |
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
|
|
|
c11cae |
(cherry picked from commit 9267342206ce17f6933d57a3128cdc504d5945c9)
|
|
|
c11cae |
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
|
|
|
c11cae |
Reviewed-by: Erik Skultety <eskultet@redhat.com>
|
|
|
c11cae |
---
|
|
|
c11cae |
src/cpu/cpu_map.xml | 3 +++
|
|
|
c11cae |
1 file changed, 3 insertions(+)
|
|
|
c11cae |
|
|
|
c11cae |
diff --git a/src/cpu/cpu_map.xml b/src/cpu/cpu_map.xml
|
|
|
c11cae |
index cee3541d24..e0c39bb690 100644
|
|
|
c11cae |
--- a/src/cpu/cpu_map.xml
|
|
|
c11cae |
+++ b/src/cpu/cpu_map.xml
|
|
|
c11cae |
@@ -436,6 +436,9 @@
|
|
|
c11cae |
<feature name='ibpb'>
|
|
|
c11cae |
<cpuid eax_in='0x80000008' ebx='0x00001000'/>
|
|
|
c11cae |
</feature>
|
|
|
c11cae |
+ <feature name='virt-ssbd'>
|
|
|
c11cae |
+ <cpuid eax_in='0x80000008' ebx='0x02000000'/>
|
|
|
c11cae |
+ </feature>
|
|
|
c11cae |
|
|
|
c11cae |
|
|
|
c11cae |
<model name='486'>
|
|
|
c11cae |
--
|
|
|
c11cae |
2.17.1
|
|
|
c11cae |
|