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Diffstat (limited to 'arch/x86/kvm/svm/sev.c')
-rw-r--r--arch/x86/kvm/svm/sev.c915
1 files changed, 876 insertions, 39 deletions
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 566f4d18185b..9858d5ae9ddd 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -14,10 +14,20 @@
#include <linux/psp-sev.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
+#include <linux/processor.h>
+#include <linux/trace_events.h>
+#include <asm/fpu/internal.h>
+
+#include <asm/trapnr.h>
#include "x86.h"
#include "svm.h"
+#include "cpuid.h"
+#include "trace.h"
+
+#define __ex(x) __kvm_handle_fault_on_reboot(x)
+static u8 sev_enc_bit;
static int sev_flush_asids(void);
static DECLARE_RWSEM(sev_deactivate_lock);
static DEFINE_MUTEX(sev_bitmap_lock);
@@ -25,7 +35,6 @@ unsigned int max_sev_asid;
static unsigned int min_sev_asid;
static unsigned long *sev_asid_bitmap;
static unsigned long *sev_reclaim_asid_bitmap;
-#define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT)
struct enc_region {
struct list_head list;
@@ -57,19 +66,19 @@ static int sev_flush_asids(void)
}
/* Must be called with the sev_bitmap_lock held */
-static bool __sev_recycle_asids(void)
+static bool __sev_recycle_asids(int min_asid, int max_asid)
{
int pos;
/* Check if there are any ASIDs to reclaim before performing a flush */
- pos = find_next_bit(sev_reclaim_asid_bitmap,
- max_sev_asid, min_sev_asid - 1);
- if (pos >= max_sev_asid)
+ pos = find_next_bit(sev_reclaim_asid_bitmap, max_sev_asid, min_asid);
+ if (pos >= max_asid)
return false;
if (sev_flush_asids())
return false;
+ /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */
bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap,
max_sev_asid);
bitmap_zero(sev_reclaim_asid_bitmap, max_sev_asid);
@@ -77,20 +86,23 @@ static bool __sev_recycle_asids(void)
return true;
}
-static int sev_asid_new(void)
+static int sev_asid_new(struct kvm_sev_info *sev)
{
+ int pos, min_asid, max_asid;
bool retry = true;
- int pos;
mutex_lock(&sev_bitmap_lock);
/*
- * SEV-enabled guest must use asid from min_sev_asid to max_sev_asid.
+ * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid.
+ * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1.
*/
+ min_asid = sev->es_active ? 0 : min_sev_asid - 1;
+ max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid;
again:
- pos = find_next_zero_bit(sev_asid_bitmap, max_sev_asid, min_sev_asid - 1);
- if (pos >= max_sev_asid) {
- if (retry && __sev_recycle_asids()) {
+ pos = find_next_zero_bit(sev_asid_bitmap, max_sev_asid, min_asid);
+ if (pos >= max_asid) {
+ if (retry && __sev_recycle_asids(min_asid, max_asid)) {
retry = false;
goto again;
}
@@ -172,7 +184,7 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
if (unlikely(sev->active))
return ret;
- asid = sev_asid_new();
+ asid = sev_asid_new(sev);
if (asid < 0)
return ret;
@@ -191,6 +203,16 @@ e_free:
return ret;
}
+static int sev_es_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+ if (!sev_es)
+ return -ENOTTY;
+
+ to_kvm_svm(kvm)->sev_info.es_active = true;
+
+ return sev_guest_init(kvm, argp);
+}
+
static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error)
{
struct sev_data_activate *data;
@@ -490,6 +512,96 @@ e_free:
return ret;
}
+static int sev_es_sync_vmsa(struct vcpu_svm *svm)
+{
+ struct vmcb_save_area *save = &svm->vmcb->save;
+
+ /* Check some debug related fields before encrypting the VMSA */
+ if (svm->vcpu.guest_debug || (save->dr7 & ~DR7_FIXED_1))
+ return -EINVAL;
+
+ /* Sync registgers */
+ save->rax = svm->vcpu.arch.regs[VCPU_REGS_RAX];
+ save->rbx = svm->vcpu.arch.regs[VCPU_REGS_RBX];
+ save->rcx = svm->vcpu.arch.regs[VCPU_REGS_RCX];
+ save->rdx = svm->vcpu.arch.regs[VCPU_REGS_RDX];
+ save->rsp = svm->vcpu.arch.regs[VCPU_REGS_RSP];
+ save->rbp = svm->vcpu.arch.regs[VCPU_REGS_RBP];
+ save->rsi = svm->vcpu.arch.regs[VCPU_REGS_RSI];
+ save->rdi = svm->vcpu.arch.regs[VCPU_REGS_RDI];
+#ifdef CONFIG_X86_64
+ save->r8 = svm->vcpu.arch.regs[VCPU_REGS_R8];
+ save->r9 = svm->vcpu.arch.regs[VCPU_REGS_R9];
+ save->r10 = svm->vcpu.arch.regs[VCPU_REGS_R10];
+ save->r11 = svm->vcpu.arch.regs[VCPU_REGS_R11];
+ save->r12 = svm->vcpu.arch.regs[VCPU_REGS_R12];
+ save->r13 = svm->vcpu.arch.regs[VCPU_REGS_R13];
+ save->r14 = svm->vcpu.arch.regs[VCPU_REGS_R14];
+ save->r15 = svm->vcpu.arch.regs[VCPU_REGS_R15];
+#endif
+ save->rip = svm->vcpu.arch.regs[VCPU_REGS_RIP];
+
+ /* Sync some non-GPR registers before encrypting */
+ save->xcr0 = svm->vcpu.arch.xcr0;
+ save->pkru = svm->vcpu.arch.pkru;
+ save->xss = svm->vcpu.arch.ia32_xss;
+
+ /*
+ * SEV-ES will use a VMSA that is pointed to by the VMCB, not
+ * the traditional VMSA that is part of the VMCB. Copy the
+ * traditional VMSA as it has been built so far (in prep
+ * for LAUNCH_UPDATE_VMSA) to be the initial SEV-ES state.
+ */
+ memcpy(svm->vmsa, save, sizeof(*save));
+
+ return 0;
+}
+
+static int sev_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+ struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
+ struct sev_data_launch_update_vmsa *vmsa;
+ int i, ret;
+
+ if (!sev_es_guest(kvm))
+ return -ENOTTY;
+
+ vmsa = kzalloc(sizeof(*vmsa), GFP_KERNEL);
+ if (!vmsa)
+ return -ENOMEM;
+
+ for (i = 0; i < kvm->created_vcpus; i++) {
+ struct vcpu_svm *svm = to_svm(kvm->vcpus[i]);
+
+ /* Perform some pre-encryption checks against the VMSA */
+ ret = sev_es_sync_vmsa(svm);
+ if (ret)
+ goto e_free;
+
+ /*
+ * The LAUNCH_UPDATE_VMSA command will perform in-place
+ * encryption of the VMSA memory content (i.e it will write
+ * the same memory region with the guest's key), so invalidate
+ * it first.
+ */
+ clflush_cache_range(svm->vmsa, PAGE_SIZE);
+
+ vmsa->handle = sev->handle;
+ vmsa->address = __sme_pa(svm->vmsa);
+ vmsa->len = PAGE_SIZE;
+ ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, vmsa,
+ &argp->error);
+ if (ret)
+ goto e_free;
+
+ svm->vcpu.arch.guest_state_protected = true;
+ }
+
+e_free:
+ kfree(vmsa);
+ return ret;
+}
+
static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp)
{
void __user *measure = (void __user *)(uintptr_t)argp->data;
@@ -932,7 +1044,7 @@ int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
struct kvm_sev_cmd sev_cmd;
int r;
- if (!svm_sev_enabled())
+ if (!svm_sev_enabled() || !sev)
return -ENOTTY;
if (!argp)
@@ -947,12 +1059,18 @@ int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
case KVM_SEV_INIT:
r = sev_guest_init(kvm, &sev_cmd);
break;
+ case KVM_SEV_ES_INIT:
+ r = sev_es_guest_init(kvm, &sev_cmd);
+ break;
case KVM_SEV_LAUNCH_START:
r = sev_launch_start(kvm, &sev_cmd);
break;
case KVM_SEV_LAUNCH_UPDATE_DATA:
r = sev_launch_update_data(kvm, &sev_cmd);
break;
+ case KVM_SEV_LAUNCH_UPDATE_VMSA:
+ r = sev_launch_update_vmsa(kvm, &sev_cmd);
+ break;
case KVM_SEV_LAUNCH_MEASURE:
r = sev_launch_measure(kvm, &sev_cmd);
break;
@@ -1125,49 +1243,61 @@ void sev_vm_destroy(struct kvm *kvm)
sev_asid_free(sev->asid);
}
-int __init sev_hardware_setup(void)
+void __init sev_hardware_setup(void)
{
- struct sev_user_data_status *status;
- int rc;
+ unsigned int eax, ebx, ecx, edx;
+ bool sev_es_supported = false;
+ bool sev_supported = false;
+
+ /* Does the CPU support SEV? */
+ if (!boot_cpu_has(X86_FEATURE_SEV))
+ goto out;
+
+ /* Retrieve SEV CPUID information */
+ cpuid(0x8000001f, &eax, &ebx, &ecx, &edx);
+
+ /* Set encryption bit location for SEV-ES guests */
+ sev_enc_bit = ebx & 0x3f;
/* Maximum number of encrypted guests supported simultaneously */
- max_sev_asid = cpuid_ecx(0x8000001F);
+ max_sev_asid = ecx;
if (!svm_sev_enabled())
- return 1;
+ goto out;
/* Minimum ASID value that should be used for SEV guest */
- min_sev_asid = cpuid_edx(0x8000001F);
+ min_sev_asid = edx;
/* Initialize SEV ASID bitmaps */
sev_asid_bitmap = bitmap_zalloc(max_sev_asid, GFP_KERNEL);
if (!sev_asid_bitmap)
- return 1;
+ goto out;
sev_reclaim_asid_bitmap = bitmap_zalloc(max_sev_asid, GFP_KERNEL);
if (!sev_reclaim_asid_bitmap)
- return 1;
+ goto out;
- status = kmalloc(sizeof(*status), GFP_KERNEL);
- if (!status)
- return 1;
+ pr_info("SEV supported: %u ASIDs\n", max_sev_asid - min_sev_asid + 1);
+ sev_supported = true;
- /*
- * Check SEV platform status.
- *
- * PLATFORM_STATUS can be called in any state, if we failed to query
- * the PLATFORM status then either PSP firmware does not support SEV
- * feature or SEV firmware is dead.
- */
- rc = sev_platform_status(status, NULL);
- if (rc)
- goto err;
+ /* SEV-ES support requested? */
+ if (!sev_es)
+ goto out;
- pr_info("SEV supported\n");
+ /* Does the CPU support SEV-ES? */
+ if (!boot_cpu_has(X86_FEATURE_SEV_ES))
+ goto out;
-err:
- kfree(status);
- return rc;
+ /* Has the system been allocated ASIDs for SEV-ES? */
+ if (min_sev_asid == 1)
+ goto out;
+
+ pr_info("SEV-ES supported: %u ASIDs\n", min_sev_asid - 1);
+ sev_es_supported = true;
+
+out:
+ sev = sev_supported;
+ sev_es = sev_es_supported;
}
void sev_hardware_teardown(void)
@@ -1181,13 +1311,329 @@ void sev_hardware_teardown(void)
sev_flush_asids();
}
+/*
+ * Pages used by hardware to hold guest encrypted state must be flushed before
+ * returning them to the system.
+ */
+static void sev_flush_guest_memory(struct vcpu_svm *svm, void *va,
+ unsigned long len)
+{
+ /*
+ * If hardware enforced cache coherency for encrypted mappings of the
+ * same physical page is supported, nothing to do.
+ */
+ if (boot_cpu_has(X86_FEATURE_SME_COHERENT))
+ return;
+
+ /*
+ * If the VM Page Flush MSR is supported, use it to flush the page
+ * (using the page virtual address and the guest ASID).
+ */
+ if (boot_cpu_has(X86_FEATURE_VM_PAGE_FLUSH)) {
+ struct kvm_sev_info *sev;
+ unsigned long va_start;
+ u64 start, stop;
+
+ /* Align start and stop to page boundaries. */
+ va_start = (unsigned long)va;
+ start = (u64)va_start & PAGE_MASK;
+ stop = PAGE_ALIGN((u64)va_start + len);
+
+ if (start < stop) {
+ sev = &to_kvm_svm(svm->vcpu.kvm)->sev_info;
+
+ while (start < stop) {
+ wrmsrl(MSR_AMD64_VM_PAGE_FLUSH,
+ start | sev->asid);
+
+ start += PAGE_SIZE;
+ }
+
+ return;
+ }
+
+ WARN(1, "Address overflow, using WBINVD\n");
+ }
+
+ /*
+ * Hardware should always have one of the above features,
+ * but if not, use WBINVD and issue a warning.
+ */
+ WARN_ONCE(1, "Using WBINVD to flush guest memory\n");
+ wbinvd_on_all_cpus();
+}
+
+void sev_free_vcpu(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_svm *svm;
+
+ if (!sev_es_guest(vcpu->kvm))
+ return;
+
+ svm = to_svm(vcpu);
+
+ if (vcpu->arch.guest_state_protected)
+ sev_flush_guest_memory(svm, svm->vmsa, PAGE_SIZE);
+ __free_page(virt_to_page(svm->vmsa));
+
+ if (svm->ghcb_sa_free)
+ kfree(svm->ghcb_sa);
+}
+
+static void dump_ghcb(struct vcpu_svm *svm)
+{
+ struct ghcb *ghcb = svm->ghcb;
+ unsigned int nbits;
+
+ /* Re-use the dump_invalid_vmcb module parameter */
+ if (!dump_invalid_vmcb) {
+ pr_warn_ratelimited("set kvm_amd.dump_invalid_vmcb=1 to dump internal KVM state.\n");
+ return;
+ }
+
+ nbits = sizeof(ghcb->save.valid_bitmap) * 8;
+
+ pr_err("GHCB (GPA=%016llx):\n", svm->vmcb->control.ghcb_gpa);
+ pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_code",
+ ghcb->save.sw_exit_code, ghcb_sw_exit_code_is_valid(ghcb));
+ pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_1",
+ ghcb->save.sw_exit_info_1, ghcb_sw_exit_info_1_is_valid(ghcb));
+ pr_err("%-20s%016llx is_valid: %u\n", "sw_exit_info_2",
+ ghcb->save.sw_exit_info_2, ghcb_sw_exit_info_2_is_valid(ghcb));
+ pr_err("%-20s%016llx is_valid: %u\n", "sw_scratch",
+ ghcb->save.sw_scratch, ghcb_sw_scratch_is_valid(ghcb));
+ pr_err("%-20s%*pb\n", "valid_bitmap", nbits, ghcb->save.valid_bitmap);
+}
+
+static void sev_es_sync_to_ghcb(struct vcpu_svm *svm)
+{
+ struct kvm_vcpu *vcpu = &svm->vcpu;
+ struct ghcb *ghcb = svm->ghcb;
+
+ /*
+ * The GHCB protocol so far allows for the following data
+ * to be returned:
+ * GPRs RAX, RBX, RCX, RDX
+ *
+ * Copy their values to the GHCB if they are dirty.
+ */
+ if (kvm_register_is_dirty(vcpu, VCPU_REGS_RAX))
+ ghcb_set_rax(ghcb, vcpu->arch.regs[VCPU_REGS_RAX]);
+ if (kvm_register_is_dirty(vcpu, VCPU_REGS_RBX))
+ ghcb_set_rbx(ghcb, vcpu->arch.regs[VCPU_REGS_RBX]);
+ if (kvm_register_is_dirty(vcpu, VCPU_REGS_RCX))
+ ghcb_set_rcx(ghcb, vcpu->arch.regs[VCPU_REGS_RCX]);
+ if (kvm_register_is_dirty(vcpu, VCPU_REGS_RDX))
+ ghcb_set_rdx(ghcb, vcpu->arch.regs[VCPU_REGS_RDX]);
+}
+
+static void sev_es_sync_from_ghcb(struct vcpu_svm *svm)
+{
+ struct vmcb_control_area *control = &svm->vmcb->control;
+ struct kvm_vcpu *vcpu = &svm->vcpu;
+ struct ghcb *ghcb = svm->ghcb;
+ u64 exit_code;
+
+ /*
+ * The GHCB protocol so far allows for the following data
+ * to be supplied:
+ * GPRs RAX, RBX, RCX, RDX
+ * XCR0
+ * CPL
+ *
+ * VMMCALL allows the guest to provide extra registers. KVM also
+ * expects RSI for hypercalls, so include that, too.
+ *
+ * Copy their values to the appropriate location if supplied.
+ */
+ memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs));
+
+ vcpu->arch.regs[VCPU_REGS_RAX] = ghcb_get_rax_if_valid(ghcb);
+ vcpu->arch.regs[VCPU_REGS_RBX] = ghcb_get_rbx_if_valid(ghcb);
+ vcpu->arch.regs[VCPU_REGS_RCX] = ghcb_get_rcx_if_valid(ghcb);
+ vcpu->arch.regs[VCPU_REGS_RDX] = ghcb_get_rdx_if_valid(ghcb);
+ vcpu->arch.regs[VCPU_REGS_RSI] = ghcb_get_rsi_if_valid(ghcb);
+
+ svm->vmcb->save.cpl = ghcb_get_cpl_if_valid(ghcb);
+
+ if (ghcb_xcr0_is_valid(ghcb)) {
+ vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb);
+ kvm_update_cpuid_runtime(vcpu);
+ }
+
+ /* Copy the GHCB exit information into the VMCB fields */
+ exit_code = ghcb_get_sw_exit_code(ghcb);
+ control->exit_code = lower_32_bits(exit_code);
+ control->exit_code_hi = upper_32_bits(exit_code);
+ control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb);
+ control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb);
+
+ /* Clear the valid entries fields */
+ memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap));
+}
+
+static int sev_es_validate_vmgexit(struct vcpu_svm *svm)
+{
+ struct kvm_vcpu *vcpu;
+ struct ghcb *ghcb;
+ u64 exit_code = 0;
+
+ ghcb = svm->ghcb;
+
+ /* Only GHCB Usage code 0 is supported */
+ if (ghcb->ghcb_usage)
+ goto vmgexit_err;
+
+ /*
+ * Retrieve the exit code now even though is may not be marked valid
+ * as it could help with debugging.
+ */
+ exit_code = ghcb_get_sw_exit_code(ghcb);
+
+ if (!ghcb_sw_exit_code_is_valid(ghcb) ||
+ !ghcb_sw_exit_info_1_is_valid(ghcb) ||
+ !ghcb_sw_exit_info_2_is_valid(ghcb))
+ goto vmgexit_err;
+
+ switch (ghcb_get_sw_exit_code(ghcb)) {
+ case SVM_EXIT_READ_DR7:
+ break;
+ case SVM_EXIT_WRITE_DR7:
+ if (!ghcb_rax_is_valid(ghcb))
+ goto vmgexit_err;
+ break;
+ case SVM_EXIT_RDTSC:
+ break;
+ case SVM_EXIT_RDPMC:
+ if (!ghcb_rcx_is_valid(ghcb))
+ goto vmgexit_err;
+ break;
+ case SVM_EXIT_CPUID:
+ if (!ghcb_rax_is_valid(ghcb) ||
+ !ghcb_rcx_is_valid(ghcb))
+ goto vmgexit_err;
+ if (ghcb_get_rax(ghcb) == 0xd)
+ if (!ghcb_xcr0_is_valid(ghcb))
+ goto vmgexit_err;
+ break;
+ case SVM_EXIT_INVD:
+ break;
+ case SVM_EXIT_IOIO:
+ if (ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_STR_MASK) {
+ if (!ghcb_sw_scratch_is_valid(ghcb))
+ goto vmgexit_err;
+ } else {
+ if (!(ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_TYPE_MASK))
+ if (!ghcb_rax_is_valid(ghcb))
+ goto vmgexit_err;
+ }
+ break;
+ case SVM_EXIT_MSR:
+ if (!ghcb_rcx_is_valid(ghcb))
+ goto vmgexit_err;
+ if (ghcb_get_sw_exit_info_1(ghcb)) {
+ if (!ghcb_rax_is_valid(ghcb) ||
+ !ghcb_rdx_is_valid(ghcb))
+ goto vmgexit_err;
+ }
+ break;
+ case SVM_EXIT_VMMCALL:
+ if (!ghcb_rax_is_valid(ghcb) ||
+ !ghcb_cpl_is_valid(ghcb))
+ goto vmgexit_err;
+ break;
+ case SVM_EXIT_RDTSCP:
+ break;
+ case SVM_EXIT_WBINVD:
+ break;
+ case SVM_EXIT_MONITOR:
+ if (!ghcb_rax_is_valid(ghcb) ||
+ !ghcb_rcx_is_valid(ghcb) ||
+ !ghcb_rdx_is_valid(ghcb))
+ goto vmgexit_err;
+ break;
+ case SVM_EXIT_MWAIT:
+ if (!ghcb_rax_is_valid(ghcb) ||
+ !ghcb_rcx_is_valid(ghcb))
+ goto vmgexit_err;
+ break;
+ case SVM_VMGEXIT_MMIO_READ:
+ case SVM_VMGEXIT_MMIO_WRITE:
+ if (!ghcb_sw_scratch_is_valid(ghcb))
+ goto vmgexit_err;
+ break;
+ case SVM_VMGEXIT_NMI_COMPLETE:
+ case SVM_VMGEXIT_AP_JUMP_TABLE:
+ case SVM_VMGEXIT_UNSUPPORTED_EVENT:
+ break;
+ default:
+ goto vmgexit_err;
+ }
+
+ return 0;
+
+vmgexit_err:
+ vcpu = &svm->vcpu;
+
+ if (ghcb->ghcb_usage) {
+ vcpu_unimpl(vcpu, "vmgexit: ghcb usage %#x is not valid\n",
+ ghcb->ghcb_usage);
+ } else {
+ vcpu_unimpl(vcpu, "vmgexit: exit reason %#llx is not valid\n",
+ exit_code);
+ dump_ghcb(svm);
+ }
+
+ vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+ vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON;
+ vcpu->run->internal.ndata = 2;
+ vcpu->run->internal.data[0] = exit_code;
+ vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu;
+
+ return -EINVAL;
+}
+
+static void pre_sev_es_run(struct vcpu_svm *svm)
+{
+ if (!svm->ghcb)
+ return;
+
+ if (svm->ghcb_sa_free) {
+ /*
+ * The scratch area lives outside the GHCB, so there is a
+ * buffer that, depending on the operation performed, may
+ * need to be synced, then freed.
+ */
+ if (svm->ghcb_sa_sync) {
+ kvm_write_guest(svm->vcpu.kvm,
+ ghcb_get_sw_scratch(svm->ghcb),
+ svm->ghcb_sa, svm->ghcb_sa_len);
+ svm->ghcb_sa_sync = false;
+ }
+
+ kfree(svm->ghcb_sa);
+ svm->ghcb_sa = NULL;
+ svm->ghcb_sa_free = false;
+ }
+
+ trace_kvm_vmgexit_exit(svm->vcpu.vcpu_id, svm->ghcb);
+
+ sev_es_sync_to_ghcb(svm);
+
+ kvm_vcpu_unmap(&svm->vcpu, &svm->ghcb_map, true);
+ svm->ghcb = NULL;
+}
+
void pre_sev_run(struct vcpu_svm *svm, int cpu)
{
struct svm_cpu_data *sd = per_cpu(svm_data, cpu);
int asid = sev_get_asid(svm->vcpu.kvm);
+ /* Perform any SEV-ES pre-run actions */
+ pre_sev_es_run(svm);
+
/* Assign the asid allocated with this SEV guest */
- svm->vmcb->control.asid = asid;
+ svm->asid = asid;
/*
* Flush guest TLB:
@@ -1203,3 +1649,394 @@ void pre_sev_run(struct vcpu_svm *svm, int cpu)
svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID;
vmcb_mark_dirty(svm->vmcb, VMCB_ASID);
}
+
+#define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE)
+static bool setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len)
+{
+ struct vmcb_control_area *control = &svm->vmcb->control;
+ struct ghcb *ghcb = svm->ghcb;
+ u64 ghcb_scratch_beg, ghcb_scratch_end;
+ u64 scratch_gpa_beg, scratch_gpa_end;
+ void *scratch_va;
+
+ scratch_gpa_beg = ghcb_get_sw_scratch(ghcb);
+ if (!scratch_gpa_beg) {
+ pr_err("vmgexit: scratch gpa not provided\n");
+ return false;
+ }
+
+ scratch_gpa_end = scratch_gpa_beg + len;
+ if (scratch_gpa_end < scratch_gpa_beg) {
+ pr_err("vmgexit: scratch length (%#llx) not valid for scratch address (%#llx)\n",
+ len, scratch_gpa_beg);
+ return false;
+ }
+
+ if ((scratch_gpa_beg & PAGE_MASK) == control->ghcb_gpa) {
+ /* Scratch area begins within GHCB */
+ ghcb_scratch_beg = control->ghcb_gpa +
+ offsetof(struct ghcb, shared_buffer);
+ ghcb_scratch_end = control->ghcb_gpa +
+ offsetof(struct ghcb, reserved_1);
+
+ /*
+ * If the scratch area begins within the GHCB, it must be
+ * completely contained in the GHCB shared buffer area.
+ */
+ if (scratch_gpa_beg < ghcb_scratch_beg ||
+ scratch_gpa_end > ghcb_scratch_end) {
+ pr_err("vmgexit: scratch area is outside of GHCB shared buffer area (%#llx - %#llx)\n",
+ scratch_gpa_beg, scratch_gpa_end);
+ return false;
+ }
+
+ scratch_va = (void *)svm->ghcb;
+ scratch_va += (scratch_gpa_beg - control->ghcb_gpa);
+ } else {
+ /*
+ * The guest memory must be read into a kernel buffer, so
+ * limit the size
+ */
+ if (len > GHCB_SCRATCH_AREA_LIMIT) {
+ pr_err("vmgexit: scratch area exceeds KVM limits (%#llx requested, %#llx limit)\n",
+ len, GHCB_SCRATCH_AREA_LIMIT);
+ return false;
+ }
+ scratch_va = kzalloc(len, GFP_KERNEL);
+ if (!scratch_va)
+ return false;
+
+ if (kvm_read_guest(svm->vcpu.kvm, scratch_gpa_beg, scratch_va, len)) {
+ /* Unable to copy scratch area from guest */
+ pr_err("vmgexit: kvm_read_guest for scratch area failed\n");
+
+ kfree(scratch_va);
+ return false;
+ }
+
+ /*
+ * The scratch area is outside the GHCB. The operation will
+ * dictate whether the buffer needs to be synced before running
+ * the vCPU next time (i.e. a read was requested so the data
+ * must be written back to the guest memory).
+ */
+ svm->ghcb_sa_sync = sync;
+ svm->ghcb_sa_free = true;
+ }
+
+ svm->ghcb_sa = scratch_va;
+ svm->ghcb_sa_len = len;
+
+ return true;
+}
+
+static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask,
+ unsigned int pos)
+{
+ svm->vmcb->control.ghcb_gpa &= ~(mask << pos);
+ svm->vmcb->control.ghcb_gpa |= (value & mask) << pos;
+}
+
+static u64 get_ghcb_msr_bits(struct vcpu_svm *svm, u64 mask, unsigned int pos)
+{
+ return (svm->vmcb->control.ghcb_gpa >> pos) & mask;
+}
+
+static void set_ghcb_msr(struct vcpu_svm *svm, u64 value)
+{
+ svm->vmcb->control.ghcb_gpa = value;
+}
+
+static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm)
+{
+ struct vmcb_control_area *control = &svm->vmcb->control;
+ struct kvm_vcpu *vcpu = &svm->vcpu;
+ u64 ghcb_info;
+ int ret = 1;
+
+ ghcb_info = control->ghcb_gpa & GHCB_MSR_INFO_MASK;
+
+ trace_kvm_vmgexit_msr_protocol_enter(svm->vcpu.vcpu_id,
+ control->ghcb_gpa);
+
+ switch (ghcb_info) {
+ case GHCB_MSR_SEV_INFO_REQ:
+ set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX,
+ GHCB_VERSION_MIN,
+ sev_enc_bit));
+ break;
+ case GHCB_MSR_CPUID_REQ: {
+ u64 cpuid_fn, cpuid_reg, cpuid_value;
+
+ cpuid_fn = get_ghcb_msr_bits(svm,
+ GHCB_MSR_CPUID_FUNC_MASK,
+ GHCB_MSR_CPUID_FUNC_POS);
+
+ /* Initialize the registers needed by the CPUID intercept */
+ vcpu->arch.regs[VCPU_REGS_RAX] = cpuid_fn;
+ vcpu->arch.regs[VCPU_REGS_RCX] = 0;
+
+ ret = svm_invoke_exit_handler(svm, SVM_EXIT_CPUID);
+ if (!ret) {
+ ret = -EINVAL;
+ break;
+ }
+
+ cpuid_reg = get_ghcb_msr_bits(svm,
+ GHCB_MSR_CPUID_REG_MASK,
+ GHCB_MSR_CPUID_REG_POS);
+ if (cpuid_reg == 0)
+ cpuid_value = vcpu->arch.regs[VCPU_REGS_RAX];
+ else if (cpuid_reg == 1)
+ cpuid_value = vcpu->arch.regs[VCPU_REGS_RBX];
+ else if (cpuid_reg == 2)
+ cpuid_value = vcpu->arch.regs[VCPU_REGS_RCX];
+ else
+ cpuid_value = vcpu->arch.regs[VCPU_REGS_RDX];
+
+ set_ghcb_msr_bits(svm, cpuid_value,
+ GHCB_MSR_CPUID_VALUE_MASK,
+ GHCB_MSR_CPUID_VALUE_POS);
+
+ set_ghcb_msr_bits(svm, GHCB_MSR_CPUID_RESP,
+ GHCB_MSR_INFO_MASK,
+ GHCB_MSR_INFO_POS);
+ break;
+ }
+ case GHCB_MSR_TERM_REQ: {
+ u64 reason_set, reason_code;
+
+ reason_set = get_ghcb_msr_bits(svm,
+ GHCB_MSR_TERM_REASON_SET_MASK,
+ GHCB_MSR_TERM_REASON_SET_POS);
+ reason_code = get_ghcb_msr_bits(svm,
+ GHCB_MSR_TERM_REASON_MASK,
+ GHCB_MSR_TERM_REASON_POS);
+ pr_info("SEV-ES guest requested termination: %#llx:%#llx\n",
+ reason_set, reason_code);
+ fallthrough;
+ }
+ default:
+ ret = -EINVAL;
+ }
+
+ trace_kvm_vmgexit_msr_protocol_exit(svm->vcpu.vcpu_id,
+ control->ghcb_gpa, ret);
+
+ return ret;
+}
+
+int sev_handle_vmgexit(struct vcpu_svm *svm)
+{
+ struct vmcb_control_area *control = &svm->vmcb->control;
+ u64 ghcb_gpa, exit_code;
+ struct ghcb *ghcb;
+ int ret;
+
+ /* Validate the GHCB */
+ ghcb_gpa = control->ghcb_gpa;
+ if (ghcb_gpa & GHCB_MSR_INFO_MASK)
+ return sev_handle_vmgexit_msr_protocol(svm);
+
+ if (!ghcb_gpa) {
+ vcpu_unimpl(&svm->vcpu, "vmgexit: GHCB gpa is not set\n");
+ return -EINVAL;
+ }
+
+ if (kvm_vcpu_map(&svm->vcpu, ghcb_gpa >> PAGE_SHIFT, &svm->ghcb_map)) {
+ /* Unable to map GHCB from guest */
+ vcpu_unimpl(&svm->vcpu, "vmgexit: error mapping GHCB [%#llx] from guest\n",
+ ghcb_gpa);
+ return -EINVAL;
+ }
+
+ svm->ghcb = svm->ghcb_map.hva;
+ ghcb = svm->ghcb_map.hva;
+
+ trace_kvm_vmgexit_enter(svm->vcpu.vcpu_id, ghcb);
+
+ exit_code = ghcb_get_sw_exit_code(ghcb);
+
+ ret = sev_es_validate_vmgexit(svm);
+ if (ret)
+ return ret;
+
+ sev_es_sync_from_ghcb(svm);
+ ghcb_set_sw_exit_info_1(ghcb, 0);
+ ghcb_set_sw_exit_info_2(ghcb, 0);
+
+ ret = -EINVAL;
+ switch (exit_code) {
+ case SVM_VMGEXIT_MMIO_READ:
+ if (!setup_vmgexit_scratch(svm, true, control->exit_info_2))
+ break;
+
+ ret = kvm_sev_es_mmio_read(&svm->vcpu,
+ control->exit_info_1,
+ control->exit_info_2,
+ svm->ghcb_sa);
+ break;
+ case SVM_VMGEXIT_MMIO_WRITE:
+ if (!setup_vmgexit_scratch(svm, false, control->exit_info_2))
+ break;
+
+ ret = kvm_sev_es_mmio_write(&svm->vcpu,
+ control->exit_info_1,
+ control->exit_info_2,
+ svm->ghcb_sa);
+ break;
+ case SVM_VMGEXIT_NMI_COMPLETE:
+ ret = svm_invoke_exit_handler(svm, SVM_EXIT_IRET);
+ break;
+ case SVM_VMGEXIT_AP_JUMP_TABLE: {
+ struct kvm_sev_info *sev = &to_kvm_svm(svm->vcpu.kvm)->sev_info;
+
+ switch (control->exit_info_1) {
+ case 0:
+ /* Set AP jump table address */
+ sev->ap_jump_table = control->exit_info_2;
+ break;
+ case 1:
+ /* Get AP jump table address */
+ ghcb_set_sw_exit_info_2(ghcb, sev->ap_jump_table);
+ break;
+ default:
+ pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n",
+ control->exit_info_1);
+ ghcb_set_sw_exit_info_1(ghcb, 1);
+ ghcb_set_sw_exit_info_2(ghcb,
+ X86_TRAP_UD |
+ SVM_EVTINJ_TYPE_EXEPT |
+ SVM_EVTINJ_VALID);
+ }
+
+ ret = 1;
+ break;
+ }
+ case SVM_VMGEXIT_UNSUPPORTED_EVENT:
+ vcpu_unimpl(&svm->vcpu,
+ "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n",
+ control->exit_info_1, control->exit_info_2);
+ break;
+ default:
+ ret = svm_invoke_exit_handler(svm, exit_code);
+ }
+
+ return ret;
+}
+
+int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in)
+{
+ if (!setup_vmgexit_scratch(svm, in, svm->vmcb->control.exit_info_2))
+ return -EINVAL;
+
+ return kvm_sev_es_string_io(&svm->vcpu, size, port,
+ svm->ghcb_sa, svm->ghcb_sa_len, in);
+}
+
+void sev_es_init_vmcb(struct vcpu_svm *svm)
+{
+ struct kvm_vcpu *vcpu = &svm->vcpu;
+
+ svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE;
+ svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK;
+
+ /*
+ * An SEV-ES guest requires a VMSA area that is a separate from the
+ * VMCB page. Do not include the encryption mask on the VMSA physical
+ * address since hardware will access it using the guest key.
+ */
+ svm->vmcb->control.vmsa_pa = __pa(svm->vmsa);
+
+ /* Can't intercept CR register access, HV can't modify CR registers */
+ svm_clr_intercept(svm, INTERCEPT_CR0_READ);
+ svm_clr_intercept(svm, INTERCEPT_CR4_READ);
+ svm_clr_intercept(svm, INTERCEPT_CR8_READ);
+ svm_clr_intercept(svm, INTERCEPT_CR0_WRITE);
+ svm_clr_intercept(svm, INTERCEPT_CR4_WRITE);
+ svm_clr_intercept(svm, INTERCEPT_CR8_WRITE);
+
+ svm_clr_intercept(svm, INTERCEPT_SELECTIVE_CR0);
+
+ /* Track EFER/CR register changes */
+ svm_set_intercept(svm, TRAP_EFER_WRITE);
+ svm_set_intercept(svm, TRAP_CR0_WRITE);
+ svm_set_intercept(svm, TRAP_CR4_WRITE);
+ svm_set_intercept(svm, TRAP_CR8_WRITE);
+
+ /* No support for enable_vmware_backdoor */
+ clr_exception_intercept(svm, GP_VECTOR);
+
+ /* Can't intercept XSETBV, HV can't modify XCR0 directly */
+ svm_clr_intercept(svm, INTERCEPT_XSETBV);
+
+ /* Clear intercepts on selected MSRs */
+ set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1);
+ set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1);
+ set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1);
+ set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1);
+ set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1);
+ set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1);
+}
+
+void sev_es_create_vcpu(struct vcpu_svm *svm)
+{
+ /*
+ * Set the GHCB MSR value as per the GHCB specification when creating
+ * a vCPU for an SEV-ES guest.
+ */
+ set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX,
+ GHCB_VERSION_MIN,
+ sev_enc_bit));
+}
+
+void sev_es_vcpu_load(struct vcpu_svm *svm, int cpu)
+{
+ struct svm_cpu_data *sd = per_cpu(svm_data, cpu);
+ struct vmcb_save_area *hostsa;
+ unsigned int i;
+
+ /*
+ * As an SEV-ES guest, hardware will restore the host state on VMEXIT,
+ * of which one step is to perform a VMLOAD. Since hardware does not
+ * perform a VMSAVE on VMRUN, the host savearea must be updated.
+ */
+ asm volatile(__ex("vmsave") : : "a" (__sme_page_pa(sd->save_area)) : "memory");
+
+ /*
+ * Certain MSRs are restored on VMEXIT, only save ones that aren't
+ * restored.
+ */
+ for (i = 0; i < NR_HOST_SAVE_USER_MSRS; i++) {
+ if (host_save_user_msrs[i].sev_es_restored)
+ continue;
+
+ rdmsrl(host_save_user_msrs[i].index, svm->host_user_msrs[i]);
+ }
+
+ /* XCR0 is restored on VMEXIT, save the current host value */
+ hostsa = (struct vmcb_save_area *)(page_address(sd->save_area) + 0x400);
+ hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
+
+ /* PKRU is restored on VMEXIT, save the curent host value */
+ hostsa->pkru = read_pkru();
+
+ /* MSR_IA32_XSS is restored on VMEXIT, save the currnet host value */
+ hostsa->xss = host_xss;
+}
+
+void sev_es_vcpu_put(struct vcpu_svm *svm)
+{
+ unsigned int i;
+
+ /*
+ * Certain MSRs are restored on VMEXIT and were saved with vmsave in
+ * sev_es_vcpu_load() above. Only restore ones that weren't.
+ */
+ for (i = 0; i < NR_HOST_SAVE_USER_MSRS; i++) {
+ if (host_save_user_msrs[i].sev_es_restored)
+ continue;
+
+ wrmsrl(host_save_user_msrs[i].index, svm->host_user_msrs[i]);
+ }
+}