Merge branch 'x86/hyperv' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

[linux-2.6-block.git] / arch / x86 / kvm / svm.c

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index b613d331d0310e1d9acdb30a01d9182236cc761a..1bf20e9160bd52b8e3bdc42d0acee6718c8037a2 100644 (file)
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -49,6 +49,7 @@
 #include <asm/debugreg.h>
 #include <asm/kvm_para.h>
 #include <asm/irq_remapping.h>
+#include <asm/nospec-branch.h>
 
 #include <asm/virtext.h>
 #include "trace.h"
@@ -404,7 +405,6 @@ static void recalc_intercepts(struct vcpu_svm *svm)
 {
        struct vmcb_control_area *c, *h;
        struct nested_state *g;
-       u32 h_intercept_exceptions;
 
        mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
 
@@ -415,14 +415,9 @@ static void recalc_intercepts(struct vcpu_svm *svm)
        h = &svm->nested.hsave->control;
        g = &svm->nested;
 
-       /* No need to intercept #UD if L1 doesn't intercept it */
-       h_intercept_exceptions =
-               h->intercept_exceptions & ~(1U << UD_VECTOR);
-
        c->intercept_cr = h->intercept_cr | g->intercept_cr;
        c->intercept_dr = h->intercept_dr | g->intercept_dr;
-       c->intercept_exceptions =
-               h_intercept_exceptions | g->intercept_exceptions;
+       c->intercept_exceptions = h->intercept_exceptions | g->intercept_exceptions;
        c->intercept = h->intercept | g->intercept;
 }
 
@@ -2500,7 +2495,6 @@ static int ud_interception(struct vcpu_svm *svm)
 {
        int er;
 
-       WARN_ON_ONCE(is_guest_mode(&svm->vcpu));
        er = emulate_instruction(&svm->vcpu, EMULTYPE_TRAP_UD);
        if (er == EMULATE_USER_EXIT)
                return 0;
@@ -5311,6 +5305,25 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
                "mov %%r13, %c[r13](%[svm]) \n\t"
                "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
                :
@@ -5341,6 +5354,9 @@ 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