58 lines
2.4 KiB
Diff
58 lines
2.4 KiB
Diff
|
From 522ce31b4998b714b03e781f49403b71531ebe5a Mon Sep 17 00:00:00 2001
|
||
|
From: "Maciej S. Szmigiero" <maciej.szmigiero@oracle.com>
|
||
|
Date: Mon, 23 May 2022 18:26:58 +0200
|
||
|
Subject: [PATCH 5/5] target/i386/kvm: Fix disabling MPX on "-cpu host" with
|
||
|
MPX-capable host
|
||
|
|
||
|
RH-Author: Ani Sinha <None>
|
||
|
RH-MergeRequest: 297: target/i386/kvm: Fix disabling MPX on "-cpu host" with MPX-capable host
|
||
|
RH-Bugzilla: 2223947
|
||
|
RH-Acked-by: Vitaly Kuznetsov <vkuznets@redhat.com>
|
||
|
RH-Acked-by: Jon Maloy <jmaloy@redhat.com>
|
||
|
RH-Commit: [1/1] 90098294a873a53b366389606fd0402efcbd70ad
|
||
|
|
||
|
Since KVM commit 5f76f6f5ff96 ("KVM: nVMX: Do not expose MPX VMX controls when guest MPX disabled")
|
||
|
it is not possible to disable MPX on a "-cpu host" just by adding "-mpx"
|
||
|
there if the host CPU does indeed support MPX.
|
||
|
QEMU will fail to set MSR_IA32_VMX_TRUE_{EXIT,ENTRY}_CTLS MSRs in this case
|
||
|
and so trigger an assertion failure.
|
||
|
|
||
|
Instead, besides "-mpx" one has to explicitly add also
|
||
|
"-vmx-exit-clear-bndcfgs" and "-vmx-entry-load-bndcfgs" to QEMU command
|
||
|
line to make it work, which is a bit convoluted.
|
||
|
|
||
|
Make the MPX-related bits in FEAT_VMX_{EXIT,ENTRY}_CTLS dependent on MPX
|
||
|
being actually enabled so such workarounds are no longer necessary.
|
||
|
|
||
|
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
|
||
|
Message-Id: <51aa2125c76363204cc23c27165e778097c33f0b.1653323077.git.maciej.szmigiero@oracle.com>
|
||
|
Cc: qemu-stable@nongnu.org
|
||
|
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
||
|
(cherry picked from commit 267b5e7e378afd260004cb37a66a6fcd641e3b53)
|
||
|
---
|
||
|
target/i386/cpu.c | 8 ++++++++
|
||
|
1 file changed, 8 insertions(+)
|
||
|
|
||
|
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
|
||
|
index 265f0aadfc..726814ee2e 100644
|
||
|
--- a/target/i386/cpu.c
|
||
|
+++ b/target/i386/cpu.c
|
||
|
@@ -1326,6 +1326,14 @@ static FeatureDep feature_dependencies[] = {
|
||
|
.from = { FEAT_7_0_EBX, CPUID_7_0_EBX_INVPCID },
|
||
|
.to = { FEAT_VMX_SECONDARY_CTLS, VMX_SECONDARY_EXEC_ENABLE_INVPCID },
|
||
|
},
|
||
|
+ {
|
||
|
+ .from = { FEAT_7_0_EBX, CPUID_7_0_EBX_MPX },
|
||
|
+ .to = { FEAT_VMX_EXIT_CTLS, VMX_VM_EXIT_CLEAR_BNDCFGS },
|
||
|
+ },
|
||
|
+ {
|
||
|
+ .from = { FEAT_7_0_EBX, CPUID_7_0_EBX_MPX },
|
||
|
+ .to = { FEAT_VMX_ENTRY_CTLS, VMX_VM_ENTRY_LOAD_BNDCFGS },
|
||
|
+ },
|
||
|
{
|
||
|
.from = { FEAT_7_0_EBX, CPUID_7_0_EBX_RDSEED },
|
||
|
.to = { FEAT_VMX_SECONDARY_CTLS, VMX_SECONDARY_EXEC_RDSEED_EXITING },
|
||
|
--
|
||
|
2.37.3
|
||
|
|