#include <linux/psp-sev.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
+#include <linux/processor.h>
#include "x86.h"
#include "svm.h"
+#include "cpuid.h"
static int sev_flush_asids(void);
static DECLARE_RWSEM(sev_deactivate_lock);
struct kvm_sev_cmd sev_cmd;
int r;
- if (!svm_sev_enabled())
+ if (!svm_sev_enabled() || !sev)
return -ENOTTY;
if (!argp)
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);
/* 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)
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));
+}
+
+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_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_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;
+
+ 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:
svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID;
vmcb_mark_dirty(svm->vmcb, VMCB_ASID);
}
+
+static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm)
+{
+ return -EINVAL;
+}
+
+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;
+
+ 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_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;
+}