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-rw-r--r--arch/x86/include/asm/cpufeatures.h1
-rw-r--r--arch/x86/include/asm/svm.h1
-rw-r--r--arch/x86/kvm/svm/sev.c36
-rw-r--r--tools/arch/x86/include/asm/cpufeatures.h1
4 files changed, 36 insertions, 3 deletions
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index cb8ca46213be..31c862d79fae 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -434,6 +434,7 @@
#define X86_FEATURE_SEV_ES (19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */
#define X86_FEATURE_V_TSC_AUX (19*32+ 9) /* "" Virtual TSC_AUX */
#define X86_FEATURE_SME_COHERENT (19*32+10) /* "" AMD hardware-enforced cache coherency */
+#define X86_FEATURE_DEBUG_SWAP (19*32+14) /* AMD SEV-ES full debug state swap support */
/* AMD-defined Extended Feature 2 EAX, CPUID level 0x80000021 (EAX), word 20 */
#define X86_FEATURE_NO_NESTED_DATA_BP (20*32+ 0) /* "" No Nested Data Breakpoints */
diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index e7c7379d6ac7..72ebd5e4e975 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -288,6 +288,7 @@ static_assert((X2AVIC_MAX_PHYSICAL_ID & AVIC_PHYSICAL_MAX_INDEX_MASK) == X2AVIC_
#define AVIC_HPA_MASK ~((0xFFFULL << 52) | 0xFFF)
+#define SVM_SEV_FEAT_DEBUG_SWAP BIT(5)
struct vmcb_seg {
u16 selector;
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index b3ef509f6fda..b7cd0cc4a19c 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -23,6 +23,7 @@
#include <asm/pkru.h>
#include <asm/trapnr.h>
#include <asm/fpu/xcr.h>
+#include <asm/debugreg.h>
#include "mmu.h"
#include "x86.h"
@@ -54,9 +55,14 @@ module_param_named(sev, sev_enabled, bool, 0444);
/* enable/disable SEV-ES support */
static bool sev_es_enabled = true;
module_param_named(sev_es, sev_es_enabled, bool, 0444);
+
+/* enable/disable SEV-ES DebugSwap support */
+static bool sev_es_debug_swap_enabled = true;
+module_param_named(debug_swap, sev_es_debug_swap_enabled, bool, 0444);
#else
#define sev_enabled false
#define sev_es_enabled false
+#define sev_es_debug_swap_enabled false
#endif /* CONFIG_KVM_AMD_SEV */
static u8 sev_enc_bit;
@@ -606,6 +612,9 @@ static int sev_es_sync_vmsa(struct vcpu_svm *svm)
save->xss = svm->vcpu.arch.ia32_xss;
save->dr6 = svm->vcpu.arch.dr6;
+ if (sev_es_debug_swap_enabled)
+ save->sev_features |= SVM_SEV_FEAT_DEBUG_SWAP;
+
pr_debug("Virtual Machine Save Area (VMSA):\n");
print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false);
@@ -2261,6 +2270,9 @@ out:
sev_enabled = sev_supported;
sev_es_enabled = sev_es_supported;
+ if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) ||
+ !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP))
+ sev_es_debug_swap_enabled = false;
#endif
}
@@ -2981,9 +2993,11 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm)
svm_set_intercept(svm, TRAP_CR8_WRITE);
vmcb->control.intercepts[INTERCEPT_DR] = 0;
- vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_READ);
- vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_WRITE);
- recalc_intercepts(svm);
+ if (!sev_es_debug_swap_enabled) {
+ vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_READ);
+ vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_WRITE);
+ recalc_intercepts(svm);
+ }
/* Can't intercept XSETBV, HV can't modify XCR0 directly */
svm_clr_intercept(svm, INTERCEPT_XSETBV);
@@ -3053,6 +3067,22 @@ void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa)
hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
hostsa->pkru = read_pkru();
hostsa->xss = host_xss;
+
+ /*
+ * If DebugSwap is enabled, debug registers are loaded but NOT saved by
+ * the CPU (Type-B). If DebugSwap is disabled/unsupported, the CPU both
+ * saves and loads debug registers (Type-A).
+ */
+ if (sev_es_debug_swap_enabled) {
+ hostsa->dr0 = native_get_debugreg(0);
+ hostsa->dr1 = native_get_debugreg(1);
+ hostsa->dr2 = native_get_debugreg(2);
+ hostsa->dr3 = native_get_debugreg(3);
+ hostsa->dr0_addr_mask = amd_get_dr_addr_mask(0);
+ hostsa->dr1_addr_mask = amd_get_dr_addr_mask(1);
+ hostsa->dr2_addr_mask = amd_get_dr_addr_mask(2);
+ hostsa->dr3_addr_mask = amd_get_dr_addr_mask(3);
+ }
}
void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector)
diff --git a/tools/arch/x86/include/asm/cpufeatures.h b/tools/arch/x86/include/asm/cpufeatures.h
index cb8ca46213be..31c862d79fae 100644
--- a/tools/arch/x86/include/asm/cpufeatures.h
+++ b/tools/arch/x86/include/asm/cpufeatures.h
@@ -434,6 +434,7 @@
#define X86_FEATURE_SEV_ES (19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */
#define X86_FEATURE_V_TSC_AUX (19*32+ 9) /* "" Virtual TSC_AUX */
#define X86_FEATURE_SME_COHERENT (19*32+10) /* "" AMD hardware-enforced cache coherency */
+#define X86_FEATURE_DEBUG_SWAP (19*32+14) /* AMD SEV-ES full debug state swap support */
/* AMD-defined Extended Feature 2 EAX, CPUID level 0x80000021 (EAX), word 20 */
#define X86_FEATURE_NO_NESTED_DATA_BP (20*32+ 0) /* "" No Nested Data Breakpoints */