lkml.org 
[lkml]   [2020]   [Sep]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC PATCH 28/35] KVM: X86: Update kvm_skip_emulated_instruction() for an SEV-ES guest
Date
From: Tom Lendacky <thomas.lendacky@amd.com>

The register state for an SEV-ES guest is encrypted so the value of the
RIP cannot be updated. For an automatic exit, the RIP will be advanced
as necessary. For a non-automatic exit, it is up to the #VC handler in
the guest to advance the RIP.

Add support to skip any RIP updates in kvm_skip_emulated_instruction()
for an SEV-ES guest.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
arch/x86/kvm/x86.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 23564d02d158..1dbdca607511 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6874,13 +6874,17 @@ static int kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu)

int kvm_skip_emulated_instruction(struct kvm_vcpu *vcpu)
{
- unsigned long rflags = kvm_x86_ops.get_rflags(vcpu);
+ unsigned long rflags;
int r;

r = kvm_x86_ops.skip_emulated_instruction(vcpu);
if (unlikely(!r))
return 0;

+ if (vcpu->arch.vmsa_encrypted)
+ return 1;
+
+ rflags = kvm_x86_ops.get_rflags(vcpu);
/*
* rflags is the old, "raw" value of the flags. The new value has
* not been saved yet.
--
2.28.0
\
 
 \ /
  Last update: 2020-09-14 22:22    [W:0.414 / U:0.256 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site