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authorJakub Kicinski <kuba@kernel.org>2022-11-18 03:19:14 +0300
committerJakub Kicinski <kuba@kernel.org>2022-11-18 05:30:39 +0300
commit224b744abf9f0663ca6762a79c7298b663fa4f04 (patch)
tree4f6a817547e7d0584d96cd539a3d63be75059cf1 /arch/x86/kvm/svm
parentb4b221bd79a1c698d9653e3ae2c3cb61cdc9aee7 (diff)
parent847ccab8fdcf4a0cd85a278480fab1ccdc9f6136 (diff)
downloadlinux-224b744abf9f0663ca6762a79c7298b663fa4f04.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/linux/bpf.h 1f6e04a1c7b8 ("bpf: Fix offset calculation error in __copy_map_value and zero_map_value") aa3496accc41 ("bpf: Refactor kptr_off_tab into btf_record") f71b2f64177a ("bpf: Refactor map->off_arr handling") https://lore.kernel.org/all/20221114095000.67a73239@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'arch/x86/kvm/svm')
-rw-r--r--arch/x86/kvm/svm/pmu.c7
-rw-r--r--arch/x86/kvm/svm/sev.c6
-rw-r--r--arch/x86/kvm/svm/svm.c115
-rw-r--r--arch/x86/kvm/svm/svm.h11
-rw-r--r--arch/x86/kvm/svm/svm_ops.h5
-rw-r--r--arch/x86/kvm/svm/vmenter.S260
6 files changed, 262 insertions, 142 deletions
diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c
index b68956299fa8..9d65cd095691 100644
--- a/arch/x86/kvm/svm/pmu.c
+++ b/arch/x86/kvm/svm/pmu.c
@@ -192,9 +192,10 @@ static void amd_pmu_init(struct kvm_vcpu *vcpu)
struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
int i;
- BUILD_BUG_ON(AMD64_NUM_COUNTERS_CORE > INTEL_PMC_MAX_GENERIC);
+ BUILD_BUG_ON(KVM_AMD_PMC_MAX_GENERIC > AMD64_NUM_COUNTERS_CORE);
+ BUILD_BUG_ON(KVM_AMD_PMC_MAX_GENERIC > INTEL_PMC_MAX_GENERIC);
- for (i = 0; i < AMD64_NUM_COUNTERS_CORE ; i++) {
+ for (i = 0; i < KVM_AMD_PMC_MAX_GENERIC ; i++) {
pmu->gp_counters[i].type = KVM_PMC_GP;
pmu->gp_counters[i].vcpu = vcpu;
pmu->gp_counters[i].idx = i;
@@ -207,7 +208,7 @@ static void amd_pmu_reset(struct kvm_vcpu *vcpu)
struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
int i;
- for (i = 0; i < AMD64_NUM_COUNTERS_CORE; i++) {
+ for (i = 0; i < KVM_AMD_PMC_MAX_GENERIC; i++) {
struct kvm_pmc *pmc = &pmu->gp_counters[i];
pmc_stop_counter(pmc);
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 28064060413a..efaaef2b7ae1 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -196,7 +196,7 @@ static void sev_asid_free(struct kvm_sev_info *sev)
__set_bit(sev->asid, sev_reclaim_asid_bitmap);
for_each_possible_cpu(cpu) {
- sd = per_cpu(svm_data, cpu);
+ sd = per_cpu_ptr(&svm_data, cpu);
sd->sev_vmcbs[sev->asid] = NULL;
}
@@ -605,7 +605,7 @@ static int sev_es_sync_vmsa(struct vcpu_svm *svm)
save->dr6 = svm->vcpu.arch.dr6;
pr_debug("Virtual Machine Save Area (VMSA):\n");
- print_hex_dump(KERN_CONT, "", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false);
+ print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, save, sizeof(*save), false);
return 0;
}
@@ -2600,7 +2600,7 @@ void sev_es_unmap_ghcb(struct vcpu_svm *svm)
void pre_sev_run(struct vcpu_svm *svm, int cpu)
{
- struct svm_cpu_data *sd = per_cpu(svm_data, cpu);
+ struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu);
int asid = sev_get_asid(svm->vcpu.kvm);
/* Assign the asid allocated with this SEV guest */
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 58f0077d9357..4b6d2b050e57 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -245,7 +245,7 @@ struct kvm_ldttss_desc {
u32 zero1;
} __attribute__((packed));
-DEFINE_PER_CPU(struct svm_cpu_data *, svm_data);
+DEFINE_PER_CPU(struct svm_cpu_data, svm_data);
/*
* Only MSR_TSC_AUX is switched via the user return hook. EFER is switched via
@@ -581,12 +581,7 @@ static int svm_hardware_enable(void)
pr_err("%s: err EOPNOTSUPP on %d\n", __func__, me);
return -EINVAL;
}
- sd = per_cpu(svm_data, me);
- if (!sd) {
- pr_err("%s: svm_data is NULL on %d\n", __func__, me);
- return -EINVAL;
- }
-
+ sd = per_cpu_ptr(&svm_data, me);
sd->asid_generation = 1;
sd->max_asid = cpuid_ebx(SVM_CPUID_FUNC) - 1;
sd->next_asid = sd->max_asid + 1;
@@ -597,7 +592,7 @@ static int svm_hardware_enable(void)
wrmsrl(MSR_EFER, efer | EFER_SVME);
- wrmsrl(MSR_VM_HSAVE_PA, __sme_page_pa(sd->save_area));
+ wrmsrl(MSR_VM_HSAVE_PA, sd->save_area_pa);
if (static_cpu_has(X86_FEATURE_TSCRATEMSR)) {
/*
@@ -646,42 +641,37 @@ static int svm_hardware_enable(void)
static void svm_cpu_uninit(int cpu)
{
- struct svm_cpu_data *sd = per_cpu(svm_data, cpu);
+ struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu);
- if (!sd)
+ if (!sd->save_area)
return;
- per_cpu(svm_data, cpu) = NULL;
kfree(sd->sev_vmcbs);
__free_page(sd->save_area);
- kfree(sd);
+ sd->save_area_pa = 0;
+ sd->save_area = NULL;
}
static int svm_cpu_init(int cpu)
{
- struct svm_cpu_data *sd;
+ struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu);
int ret = -ENOMEM;
- sd = kzalloc(sizeof(struct svm_cpu_data), GFP_KERNEL);
- if (!sd)
- return ret;
- sd->cpu = cpu;
+ memset(sd, 0, sizeof(struct svm_cpu_data));
sd->save_area = alloc_page(GFP_KERNEL | __GFP_ZERO);
if (!sd->save_area)
- goto free_cpu_data;
+ return ret;
ret = sev_cpu_init(sd);
if (ret)
goto free_save_area;
- per_cpu(svm_data, cpu) = sd;
-
+ sd->save_area_pa = __sme_page_pa(sd->save_area);
return 0;
free_save_area:
__free_page(sd->save_area);
-free_cpu_data:
- kfree(sd);
+ sd->save_area = NULL;
return ret;
}
@@ -730,6 +720,15 @@ static bool msr_write_intercepted(struct kvm_vcpu *vcpu, u32 msr)
u32 offset;
u32 *msrpm;
+ /*
+ * For non-nested case:
+ * If the L01 MSR bitmap does not intercept the MSR, then we need to
+ * save it.
+ *
+ * For nested case:
+ * If the L02 MSR bitmap does not intercept the MSR, then we need to
+ * save it.
+ */
msrpm = is_guest_mode(vcpu) ? to_svm(vcpu)->nested.msrpm:
to_svm(vcpu)->msrpm;
@@ -1425,7 +1424,7 @@ static void svm_clear_current_vmcb(struct vmcb *vmcb)
int i;
for_each_online_cpu(i)
- cmpxchg(&per_cpu(svm_data, i)->current_vmcb, vmcb, NULL);
+ cmpxchg(per_cpu_ptr(&svm_data.current_vmcb, i), vmcb, NULL);
}
static void svm_vcpu_free(struct kvm_vcpu *vcpu)
@@ -1450,7 +1449,7 @@ static void svm_vcpu_free(struct kvm_vcpu *vcpu)
static void svm_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
- struct svm_cpu_data *sd = per_cpu(svm_data, vcpu->cpu);
+ struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, vcpu->cpu);
if (sev_es_guest(vcpu->kvm))
sev_es_unmap_ghcb(svm);
@@ -1462,7 +1461,7 @@ static void svm_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
* Save additional host state that will be restored on VMEXIT (sev-es)
* or subsequent vmload of host save area.
*/
- vmsave(__sme_page_pa(sd->save_area));
+ vmsave(sd->save_area_pa);
if (sev_es_guest(vcpu->kvm)) {
struct sev_es_save_area *hostsa;
hostsa = (struct sev_es_save_area *)(page_address(sd->save_area) + 0x400);
@@ -1487,7 +1486,7 @@ static void svm_prepare_host_switch(struct kvm_vcpu *vcpu)
static void svm_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
- struct svm_cpu_data *sd = per_cpu(svm_data, cpu);
+ struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu);
if (sd->current_vmcb != svm->vmcb) {
sd->current_vmcb = svm->vmcb;
@@ -2710,9 +2709,9 @@ static int svm_get_msr_feature(struct kvm_msr_entry *msr)
msr->data = 0;
switch (msr->index) {
- case MSR_F10H_DECFG:
- if (boot_cpu_has(X86_FEATURE_LFENCE_RDTSC))
- msr->data |= MSR_F10H_DECFG_LFENCE_SERIALIZE;
+ case MSR_AMD64_DE_CFG:
+ if (cpu_feature_enabled(X86_FEATURE_LFENCE_RDTSC))
+ msr->data |= MSR_AMD64_DE_CFG_LFENCE_SERIALIZE;
break;
case MSR_IA32_PERF_CAPABILITIES:
return 0;
@@ -2813,7 +2812,7 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
msr_info->data = 0x1E;
}
break;
- case MSR_F10H_DECFG:
+ case MSR_AMD64_DE_CFG:
msr_info->data = svm->msr_decfg;
break;
default:
@@ -3042,7 +3041,7 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
case MSR_VM_IGNNE:
vcpu_unimpl(vcpu, "unimplemented wrmsr: 0x%x data 0x%llx\n", ecx, data);
break;
- case MSR_F10H_DECFG: {
+ case MSR_AMD64_DE_CFG: {
struct kvm_msr_entry msr_entry;
msr_entry.index = msr->index;
@@ -3443,7 +3442,7 @@ static int svm_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
static void reload_tss(struct kvm_vcpu *vcpu)
{
- struct svm_cpu_data *sd = per_cpu(svm_data, vcpu->cpu);
+ struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, vcpu->cpu);
sd->tss_desc->type = 9; /* available 32/64-bit TSS */
load_TR_desc();
@@ -3451,7 +3450,7 @@ static void reload_tss(struct kvm_vcpu *vcpu)
static void pre_svm_run(struct kvm_vcpu *vcpu)
{
- struct svm_cpu_data *sd = per_cpu(svm_data, vcpu->cpu);
+ struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, vcpu->cpu);
struct vcpu_svm *svm = to_svm(vcpu);
/*
@@ -3911,30 +3910,16 @@ static fastpath_t svm_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
return EXIT_FASTPATH_NONE;
}
-static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
+static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu, bool spec_ctrl_intercepted)
{
struct vcpu_svm *svm = to_svm(vcpu);
- unsigned long vmcb_pa = svm->current_vmcb->pa;
guest_state_enter_irqoff();
- if (sev_es_guest(vcpu->kvm)) {
- __svm_sev_es_vcpu_run(vmcb_pa);
- } else {
- struct svm_cpu_data *sd = per_cpu(svm_data, vcpu->cpu);
-
- /*
- * Use a single vmcb (vmcb01 because it's always valid) for
- * context switching guest state via VMLOAD/VMSAVE, that way
- * the state doesn't need to be copied between vmcb01 and
- * vmcb02 when switching vmcbs for nested virtualization.
- */
- vmload(svm->vmcb01.pa);
- __svm_vcpu_run(vmcb_pa, (unsigned long *)&vcpu->arch.regs);
- vmsave(svm->vmcb01.pa);
-
- vmload(__sme_page_pa(sd->save_area));
- }
+ if (sev_es_guest(vcpu->kvm))
+ __svm_sev_es_vcpu_run(svm, spec_ctrl_intercepted);
+ else
+ __svm_vcpu_run(svm, spec_ctrl_intercepted);
guest_state_exit_irqoff();
}
@@ -3942,6 +3927,7 @@ static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
+ bool spec_ctrl_intercepted = msr_write_intercepted(vcpu, MSR_IA32_SPEC_CTRL);
trace_kvm_entry(vcpu);
@@ -3998,34 +3984,15 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
* being speculatively taken.
*/
if (!static_cpu_has(X86_FEATURE_V_SPEC_CTRL))
- x86_spec_ctrl_set_guest(svm->spec_ctrl, svm->virt_spec_ctrl);
+ x86_spec_ctrl_set_guest(svm->virt_spec_ctrl);
- svm_vcpu_enter_exit(vcpu);
-
- /*
- * We do not use IBRS in the kernel. If this vCPU has used the
- * SPEC_CTRL MSR it may have left it on; save the value and
- * turn it off. This is much more efficient than blindly adding
- * it to the atomic save/restore list. Especially as the former
- * (Saving guest MSRs on vmexit) doesn't even exist in KVM.
- *
- * For non-nested case:
- * If the L01 MSR bitmap does not intercept the MSR, then we need to
- * save it.
- *
- * For nested case:
- * If the L02 MSR bitmap does not intercept the MSR, then we need to
- * save it.
- */
- if (!static_cpu_has(X86_FEATURE_V_SPEC_CTRL) &&
- unlikely(!msr_write_intercepted(vcpu, MSR_IA32_SPEC_CTRL)))
- svm->spec_ctrl = native_read_msr(MSR_IA32_SPEC_CTRL);
+ svm_vcpu_enter_exit(vcpu, spec_ctrl_intercepted);
if (!sev_es_guest(vcpu->kvm))
reload_tss(vcpu);
if (!static_cpu_has(X86_FEATURE_V_SPEC_CTRL))
- x86_spec_ctrl_restore_host(svm->spec_ctrl, svm->virt_spec_ctrl);
+ x86_spec_ctrl_restore_host(svm->virt_spec_ctrl);
if (!sev_es_guest(vcpu->kvm)) {
vcpu->arch.cr2 = svm->vmcb->save.cr2;
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 6a7686bf6900..199a2ecef1ce 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -209,7 +209,6 @@ struct vcpu_svm {
struct vmcb *vmcb;
struct kvm_vmcb_info vmcb01;
struct kvm_vmcb_info *current_vmcb;
- struct svm_cpu_data *svm_data;
u32 asid;
u32 sysenter_esp_hi;
u32 sysenter_eip_hi;
@@ -281,8 +280,6 @@ struct vcpu_svm {
};
struct svm_cpu_data {
- int cpu;
-
u64 asid_generation;
u32 max_asid;
u32 next_asid;
@@ -290,13 +287,15 @@ struct svm_cpu_data {
struct kvm_ldttss_desc *tss_desc;
struct page *save_area;
+ unsigned long save_area_pa;
+
struct vmcb *current_vmcb;
/* index = sev_asid, value = vmcb pointer */
struct vmcb **sev_vmcbs;
};
-DECLARE_PER_CPU(struct svm_cpu_data *, svm_data);
+DECLARE_PER_CPU(struct svm_cpu_data, svm_data);
void recalc_intercepts(struct vcpu_svm *svm);
@@ -683,7 +682,7 @@ void sev_es_unmap_ghcb(struct vcpu_svm *svm);
/* vmenter.S */
-void __svm_sev_es_vcpu_run(unsigned long vmcb_pa);
-void __svm_vcpu_run(unsigned long vmcb_pa, unsigned long *regs);
+void __svm_sev_es_vcpu_run(struct vcpu_svm *svm, bool spec_ctrl_intercepted);
+void __svm_vcpu_run(struct vcpu_svm *svm, bool spec_ctrl_intercepted);
#endif
diff --git a/arch/x86/kvm/svm/svm_ops.h b/arch/x86/kvm/svm/svm_ops.h
index 9430d6437c9f..36c8af87a707 100644
--- a/arch/x86/kvm/svm/svm_ops.h
+++ b/arch/x86/kvm/svm/svm_ops.h
@@ -61,9 +61,4 @@ static __always_inline void vmsave(unsigned long pa)
svm_asm1(vmsave, "a" (pa), "memory");
}
-static __always_inline void vmload(unsigned long pa)
-{
- svm_asm1(vmload, "a" (pa), "memory");
-}
-
#endif /* __KVM_X86_SVM_OPS_H */
diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index 723f8534986c..34367dc203f2 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -4,35 +4,97 @@
#include <asm/bitsperlong.h>
#include <asm/kvm_vcpu_regs.h>
#include <asm/nospec-branch.h>
+#include "kvm-asm-offsets.h"
#define WORD_SIZE (BITS_PER_LONG / 8)
/* Intentionally omit RAX as it's context switched by hardware */
-#define VCPU_RCX __VCPU_REGS_RCX * WORD_SIZE
-#define VCPU_RDX __VCPU_REGS_RDX * WORD_SIZE
-#define VCPU_RBX __VCPU_REGS_RBX * WORD_SIZE
+#define VCPU_RCX (SVM_vcpu_arch_regs + __VCPU_REGS_RCX * WORD_SIZE)
+#define VCPU_RDX (SVM_vcpu_arch_regs + __VCPU_REGS_RDX * WORD_SIZE)
+#define VCPU_RBX (SVM_vcpu_arch_regs + __VCPU_REGS_RBX * WORD_SIZE)
/* Intentionally omit RSP as it's context switched by hardware */
-#define VCPU_RBP __VCPU_REGS_RBP * WORD_SIZE
-#define VCPU_RSI __VCPU_REGS_RSI * WORD_SIZE
-#define VCPU_RDI __VCPU_REGS_RDI * WORD_SIZE
+#define VCPU_RBP (SVM_vcpu_arch_regs + __VCPU_REGS_RBP * WORD_SIZE)
+#define VCPU_RSI (SVM_vcpu_arch_regs + __VCPU_REGS_RSI * WORD_SIZE)
+#define VCPU_RDI (SVM_vcpu_arch_regs + __VCPU_REGS_RDI * WORD_SIZE)
#ifdef CONFIG_X86_64
-#define VCPU_R8 __VCPU_REGS_R8 * WORD_SIZE
-#define VCPU_R9 __VCPU_REGS_R9 * WORD_SIZE
-#define VCPU_R10 __VCPU_REGS_R10 * WORD_SIZE
-#define VCPU_R11 __VCPU_REGS_R11 * WORD_SIZE
-#define VCPU_R12 __VCPU_REGS_R12 * WORD_SIZE
-#define VCPU_R13 __VCPU_REGS_R13 * WORD_SIZE
-#define VCPU_R14 __VCPU_REGS_R14 * WORD_SIZE
-#define VCPU_R15 __VCPU_REGS_R15 * WORD_SIZE
+#define VCPU_R8 (SVM_vcpu_arch_regs + __VCPU_REGS_R8 * WORD_SIZE)
+#define VCPU_R9 (SVM_vcpu_arch_regs + __VCPU_REGS_R9 * WORD_SIZE)
+#define VCPU_R10 (SVM_vcpu_arch_regs + __VCPU_REGS_R10 * WORD_SIZE)
+#define VCPU_R11 (SVM_vcpu_arch_regs + __VCPU_REGS_R11 * WORD_SIZE)
+#define VCPU_R12 (SVM_vcpu_arch_regs + __VCPU_REGS_R12 * WORD_SIZE)
+#define VCPU_R13 (SVM_vcpu_arch_regs + __VCPU_REGS_R13 * WORD_SIZE)
+#define VCPU_R14 (SVM_vcpu_arch_regs + __VCPU_REGS_R14 * WORD_SIZE)
+#define VCPU_R15 (SVM_vcpu_arch_regs + __VCPU_REGS_R15 * WORD_SIZE)
#endif
+#define SVM_vmcb01_pa (SVM_vmcb01 + KVM_VMCB_pa)
+
.section .noinstr.text, "ax"
+.macro RESTORE_GUEST_SPEC_CTRL
+ /* No need to do anything if SPEC_CTRL is unset or V_SPEC_CTRL is set */
+ ALTERNATIVE_2 "", \
+ "jmp 800f", X86_FEATURE_MSR_SPEC_CTRL, \
+ "", X86_FEATURE_V_SPEC_CTRL
+801:
+.endm
+.macro RESTORE_GUEST_SPEC_CTRL_BODY
+800:
+ /*
+ * SPEC_CTRL handling: if the guest's SPEC_CTRL value differs from the
+ * host's, write the MSR. This is kept out-of-line so that the common
+ * case does not have to jump.
+ *
+ * IMPORTANT: To avoid RSB underflow attacks and any other nastiness,
+ * there must not be any returns or indirect branches between this code
+ * and vmentry.
+ */
+ movl SVM_spec_ctrl(%_ASM_DI), %eax
+ cmp PER_CPU_VAR(x86_spec_ctrl_current), %eax
+ je 801b
+ mov $MSR_IA32_SPEC_CTRL, %ecx
+ xor %edx, %edx
+ wrmsr
+ jmp 801b
+.endm
+
+.macro RESTORE_HOST_SPEC_CTRL
+ /* No need to do anything if SPEC_CTRL is unset or V_SPEC_CTRL is set */
+ ALTERNATIVE_2 "", \
+ "jmp 900f", X86_FEATURE_MSR_SPEC_CTRL, \
+ "", X86_FEATURE_V_SPEC_CTRL
+901:
+.endm
+.macro RESTORE_HOST_SPEC_CTRL_BODY
+900:
+ /* Same for after vmexit. */
+ mov $MSR_IA32_SPEC_CTRL, %ecx
+
+ /*
+ * Load the value that the guest had written into MSR_IA32_SPEC_CTRL,
+ * if it was not intercepted during guest execution.
+ */
+ cmpb $0, (%_ASM_SP)
+ jnz 998f
+ rdmsr
+ movl %eax, SVM_spec_ctrl(%_ASM_DI)
+998:
+
+ /* Now restore the host value of the MSR if different from the guest's. */
+ movl PER_CPU_VAR(x86_spec_ctrl_current), %eax
+ cmp SVM_spec_ctrl(%_ASM_DI), %eax
+ je 901b
+ xor %edx, %edx
+ wrmsr
+ jmp 901b
+.endm
+
+
/**
* __svm_vcpu_run - Run a vCPU via a transition to SVM guest mode
- * @vmcb_pa: unsigned long
- * @regs: unsigned long * (to guest registers)
+ * @svm: struct vcpu_svm *
+ * @spec_ctrl_intercepted: bool
*/
SYM_FUNC_START(__svm_vcpu_run)
push %_ASM_BP
@@ -47,49 +109,71 @@ SYM_FUNC_START(__svm_vcpu_run)
#endif
push %_ASM_BX
- /* Save @regs. */
+ /*
+ * Save variables needed after vmexit on the stack, in inverse
+ * order compared to when they are needed.
+ */
+
+ /* Accessed directly from the stack in RESTORE_HOST_SPEC_CTRL. */
push %_ASM_ARG2
- /* Save @vmcb. */
+ /* Needed to restore access to percpu variables. */
+ __ASM_SIZE(push) PER_CPU_VAR(svm_data + SD_save_area_pa)
+
+ /* Finally save @svm. */
push %_ASM_ARG1
- /* Move @regs to RAX. */
- mov %_ASM_ARG2, %_ASM_AX
+.ifnc _ASM_ARG1, _ASM_DI
+ /*
+ * Stash @svm in RDI early. On 32-bit, arguments are in RAX, RCX
+ * and RDX which are clobbered by RESTORE_GUEST_SPEC_CTRL.
+ */
+ mov %_ASM_ARG1, %_ASM_DI
+.endif
+
+ /* Clobbers RAX, RCX, RDX. */
+ RESTORE_GUEST_SPEC_CTRL
+
+ /*
+ * Use a single vmcb (vmcb01 because it's always valid) for
+ * context switching guest state via VMLOAD/VMSAVE, that way
+ * the state doesn't need to be copied between vmcb01 and
+ * vmcb02 when switching vmcbs for nested virtualization.
+ */
+ mov SVM_vmcb01_pa(%_ASM_DI), %_ASM_AX
+1: vmload %_ASM_AX
+2:
+
+ /* Get svm->current_vmcb->pa into RAX. */
+ mov SVM_current_vmcb(%_ASM_DI), %_ASM_AX
+ mov KVM_VMCB_pa(%_ASM_AX), %_ASM_AX
/* Load guest registers. */
- mov VCPU_RCX(%_ASM_AX), %_ASM_CX
- mov VCPU_RDX(%_ASM_AX), %_ASM_DX
- mov VCPU_RBX(%_ASM_AX), %_ASM_BX
- mov VCPU_RBP(%_ASM_AX), %_ASM_BP
- mov VCPU_RSI(%_ASM_AX), %_ASM_SI
- mov VCPU_RDI(%_ASM_AX), %_ASM_DI
+ mov VCPU_RCX(%_ASM_DI), %_ASM_CX
+ mov VCPU_RDX(%_ASM_DI), %_ASM_DX
+ mov VCPU_RBX(%_ASM_DI), %_ASM_BX
+ mov VCPU_RBP(%_ASM_DI), %_ASM_BP
+ mov VCPU_RSI(%_ASM_DI), %_ASM_SI
#ifdef CONFIG_X86_64
- mov VCPU_R8 (%_ASM_AX), %r8
- mov VCPU_R9 (%_ASM_AX), %r9
- mov VCPU_R10(%_ASM_AX), %r10
- mov VCPU_R11(%_ASM_AX), %r11
- mov VCPU_R12(%_ASM_AX), %r12
- mov VCPU_R13(%_ASM_AX), %r13
- mov VCPU_R14(%_ASM_AX), %r14
- mov VCPU_R15(%_ASM_AX), %r15
+ mov VCPU_R8 (%_ASM_DI), %r8
+ mov VCPU_R9 (%_ASM_DI), %r9
+ mov VCPU_R10(%_ASM_DI), %r10
+ mov VCPU_R11(%_ASM_DI), %r11
+ mov VCPU_R12(%_ASM_DI), %r12
+ mov VCPU_R13(%_ASM_DI), %r13
+ mov VCPU_R14(%_ASM_DI), %r14
+ mov VCPU_R15(%_ASM_DI), %r15
#endif
-
- /* "POP" @vmcb to RAX. */
- pop %_ASM_AX
+ mov VCPU_RDI(%_ASM_DI), %_ASM_DI
/* Enter guest mode */
sti
-1: vmrun %_ASM_AX
-
-2: cli
-
-#ifdef CONFIG_RETPOLINE
- /* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */
- FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE
-#endif
+3: vmrun %_ASM_AX
+4:
+ cli
- /* "POP" @regs to RAX. */
+ /* Pop @svm to RAX while it's the only available register. */
pop %_ASM_AX
/* Save all guest registers. */
@@ -110,6 +194,26 @@ SYM_FUNC_START(__svm_vcpu_run)
mov %r15, VCPU_R15(%_ASM_AX)
#endif
+ /* @svm can stay in RDI from now on. */
+ mov %_ASM_AX, %_ASM_DI
+
+ mov SVM_vmcb01_pa(%_ASM_DI), %_ASM_AX
+5: vmsave %_ASM_AX
+6:
+
+ /* Restores GSBASE among other things, allowing access to percpu data. */
+ pop %_ASM_AX
+7: vmload %_ASM_AX
+8:
+
+#ifdef CONFIG_RETPOLINE
+ /* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */
+ FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE
+#endif
+
+ /* Clobbers RAX, RCX, RDX. */
+ RESTORE_HOST_SPEC_CTRL
+
/*
* Mitigate RETBleed for AMD/Hygon Zen uarch. RET should be
* untrained as soon as we exit the VM and are back to the
@@ -145,6 +249,9 @@ SYM_FUNC_START(__svm_vcpu_run)
xor %r15d, %r15d
#endif
+ /* "Pop" @spec_ctrl_intercepted. */
+ pop %_ASM_BX
+
pop %_ASM_BX
#ifdef CONFIG_X86_64
@@ -159,17 +266,33 @@ SYM_FUNC_START(__svm_vcpu_run)
pop %_ASM_BP
RET
-3: cmpb $0, kvm_rebooting
+ RESTORE_GUEST_SPEC_CTRL_BODY
+ RESTORE_HOST_SPEC_CTRL_BODY
+
+10: cmpb $0, kvm_rebooting
jne 2b
ud2
+30: cmpb $0, kvm_rebooting
+ jne 4b
+ ud2
+50: cmpb $0, kvm_rebooting
+ jne 6b
+ ud2
+70: cmpb $0, kvm_rebooting
+ jne 8b
+ ud2
- _ASM_EXTABLE(1b, 3b)
+ _ASM_EXTABLE(1b, 10b)
+ _ASM_EXTABLE(3b, 30b)
+ _ASM_EXTABLE(5b, 50b)
+ _ASM_EXTABLE(7b, 70b)
SYM_FUNC_END(__svm_vcpu_run)
/**
* __svm_sev_es_vcpu_run - Run a SEV-ES vCPU via a transition to SVM guest mode
- * @vmcb_pa: unsigned long
+ * @svm: struct vcpu_svm *
+ * @spec_ctrl_intercepted: bool
*/
SYM_FUNC_START(__svm_sev_es_vcpu_run)
push %_ASM_BP
@@ -184,8 +307,31 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run)
#endif
push %_ASM_BX
- /* Move @vmcb to RAX. */
- mov %_ASM_ARG1, %_ASM_AX
+ /*
+ * Save variables needed after vmexit on the stack, in inverse
+ * order compared to when they are needed.
+ */
+
+ /* Accessed directly from the stack in RESTORE_HOST_SPEC_CTRL. */
+ push %_ASM_ARG2
+
+ /* Save @svm. */
+ push %_ASM_ARG1
+
+.ifnc _ASM_ARG1, _ASM_DI
+ /*
+ * Stash @svm in RDI early. On 32-bit, arguments are in RAX, RCX
+ * and RDX which are clobbered by RESTORE_GUEST_SPEC_CTRL.
+ */
+ mov %_ASM_ARG1, %_ASM_DI
+.endif
+
+ /* Clobbers RAX, RCX, RDX. */
+ RESTORE_GUEST_SPEC_CTRL
+
+ /* Get svm->current_vmcb->pa into RAX. */
+ mov SVM_current_vmcb(%_ASM_DI), %_ASM_AX
+ mov KVM_VMCB_pa(%_ASM_AX), %_ASM_AX
/* Enter guest mode */
sti
@@ -194,11 +340,17 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run)
2: cli
+ /* Pop @svm to RDI, guest registers have been saved already. */
+ pop %_ASM_DI
+
#ifdef CONFIG_RETPOLINE
/* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */
FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE
#endif
+ /* Clobbers RAX, RCX, RDX. */
+ RESTORE_HOST_SPEC_CTRL
+
/*
* Mitigate RETBleed for AMD/Hygon Zen uarch. RET should be
* untrained as soon as we exit the VM and are back to the
@@ -208,6 +360,9 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run)
*/
UNTRAIN_RET
+ /* "Pop" @spec_ctrl_intercepted. */
+ pop %_ASM_BX
+
pop %_ASM_BX
#ifdef CONFIG_X86_64
@@ -222,6 +377,9 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run)
pop %_ASM_BP
RET
+ RESTORE_GUEST_SPEC_CTRL_BODY
+ RESTORE_HOST_SPEC_CTRL_BODY
+
3: cmpb $0, kvm_rebooting
jne 2b
ud2