summaryrefslogtreecommitdiff
path: root/arch/x86/kvm/svm.c
diff options
context:
space:
mode:
authorMax Krummenacher <max.krummenacher@toradex.com>2018-03-13 11:32:58 +0100
committerMax Krummenacher <max.krummenacher@toradex.com>2018-03-13 11:32:58 +0100
commit6fb9f3c8a4992f67dcb3ce413df2e22e96b2d400 (patch)
tree6e3071b2f179a62b027669ac2a238383293bf941 /arch/x86/kvm/svm.c
parenta126a5e5dc2fcc5cb36af14c89b440cc8e3bab30 (diff)
parent8b5ab55d254f36e89b1b53aeac7223d2d102483e (diff)
Merge tag 'v4.4.121' into toradex_vf_4.4-nextColibri-VF_LXDE-Image_2.8b2.97-20180331
This is the 4.4.121 stable release
Diffstat (limited to 'arch/x86/kvm/svm.c')
-rw-r--r--arch/x86/kvm/svm.c23
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 4b1152e57340..2038e5bacce6 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -37,6 +37,7 @@
#include <asm/desc.h>
#include <asm/debugreg.h>
#include <asm/kvm_para.h>
+#include <asm/nospec-branch.h>
#include <asm/virtext.h>
#include "trace.h"
@@ -3856,6 +3857,25 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
"mov %%r14, %c[r14](%[svm]) \n\t"
"mov %%r15, %c[r15](%[svm]) \n\t"
#endif
+ /*
+ * Clear host registers marked as clobbered to prevent
+ * speculative use.
+ */
+ "xor %%" _ASM_BX ", %%" _ASM_BX " \n\t"
+ "xor %%" _ASM_CX ", %%" _ASM_CX " \n\t"
+ "xor %%" _ASM_DX ", %%" _ASM_DX " \n\t"
+ "xor %%" _ASM_SI ", %%" _ASM_SI " \n\t"
+ "xor %%" _ASM_DI ", %%" _ASM_DI " \n\t"
+#ifdef CONFIG_X86_64
+ "xor %%r8, %%r8 \n\t"
+ "xor %%r9, %%r9 \n\t"
+ "xor %%r10, %%r10 \n\t"
+ "xor %%r11, %%r11 \n\t"
+ "xor %%r12, %%r12 \n\t"
+ "xor %%r13, %%r13 \n\t"
+ "xor %%r14, %%r14 \n\t"
+ "xor %%r15, %%r15 \n\t"
+#endif
"pop %%" _ASM_BP
:
: [svm]"a"(svm),
@@ -3885,6 +3905,9 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
#endif
);
+ /* Eliminate branch target predictions from guest mode */
+ vmexit_fill_RSB();
+
#ifdef CONFIG_X86_64
wrmsrl(MSR_GS_BASE, svm->host.gs_base);
#else