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Diffstat (limited to 'arch/x86/kvm/svm/sev.c')
-rw-r--r--arch/x86/kvm/svm/sev.c121
1 files changed, 71 insertions, 50 deletions
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 17b53457d866..75fa6dd268f0 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -258,6 +258,7 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
goto e_free;
INIT_LIST_HEAD(&sev->regions_list);
+ INIT_LIST_HEAD(&sev->mirror_vms);
return 0;
@@ -1623,9 +1624,12 @@ static void sev_unlock_vcpus_for_migration(struct kvm *kvm)
}
}
-static void sev_migrate_from(struct kvm_sev_info *dst,
- struct kvm_sev_info *src)
+static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm)
{
+ struct kvm_sev_info *dst = &to_kvm_svm(dst_kvm)->sev_info;
+ struct kvm_sev_info *src = &to_kvm_svm(src_kvm)->sev_info;
+ struct kvm_sev_info *mirror;
+
dst->active = true;
dst->asid = src->asid;
dst->handle = src->handle;
@@ -1639,6 +1643,30 @@ static void sev_migrate_from(struct kvm_sev_info *dst,
src->enc_context_owner = NULL;
list_cut_before(&dst->regions_list, &src->regions_list, &src->regions_list);
+
+ /*
+ * If this VM has mirrors, "transfer" each mirror's refcount of the
+ * source to the destination (this KVM). The caller holds a reference
+ * to the source, so there's no danger of use-after-free.
+ */
+ list_cut_before(&dst->mirror_vms, &src->mirror_vms, &src->mirror_vms);
+ list_for_each_entry(mirror, &dst->mirror_vms, mirror_entry) {
+ kvm_get_kvm(dst_kvm);
+ kvm_put_kvm(src_kvm);
+ mirror->enc_context_owner = dst_kvm;
+ }
+
+ /*
+ * If this VM is a mirror, remove the old mirror from the owners list
+ * and add the new mirror to the list.
+ */
+ if (is_mirroring_enc_context(dst_kvm)) {
+ struct kvm_sev_info *owner_sev_info =
+ &to_kvm_svm(dst->enc_context_owner)->sev_info;
+
+ list_del(&src->mirror_entry);
+ list_add_tail(&dst->mirror_entry, &owner_sev_info->mirror_vms);
+ }
}
static int sev_es_migrate_from(struct kvm *dst, struct kvm *src)
@@ -1681,7 +1709,7 @@ static int sev_es_migrate_from(struct kvm *dst, struct kvm *src)
return 0;
}
-int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd)
+int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd)
{
struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info;
struct kvm_sev_info *src_sev, *cg_cleanup_sev;
@@ -1708,15 +1736,6 @@ int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd)
src_sev = &to_kvm_svm(source_kvm)->sev_info;
- /*
- * VMs mirroring src's encryption context rely on it to keep the
- * ASID allocated, but below we are clearing src_sev->asid.
- */
- if (src_sev->num_mirrored_vms) {
- ret = -EBUSY;
- goto out_unlock;
- }
-
dst_sev->misc_cg = get_current_misc_cg();
cg_cleanup_sev = dst_sev;
if (dst_sev->misc_cg != src_sev->misc_cg) {
@@ -1738,7 +1757,8 @@ int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd)
if (ret)
goto out_source_vcpu;
}
- sev_migrate_from(dst_sev, src_sev);
+
+ sev_migrate_from(kvm, source_kvm);
kvm_vm_dead(source_kvm);
cg_cleanup_sev = src_sev;
ret = 0;
@@ -1761,7 +1781,7 @@ out_fput:
return ret;
}
-int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
+int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
struct kvm_sev_cmd sev_cmd;
int r;
@@ -1858,8 +1878,8 @@ out:
return r;
}
-int svm_register_enc_region(struct kvm *kvm,
- struct kvm_enc_region *range)
+int sev_mem_enc_register_region(struct kvm *kvm,
+ struct kvm_enc_region *range)
{
struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
struct enc_region *region;
@@ -1932,8 +1952,8 @@ static void __unregister_enc_region_locked(struct kvm *kvm,
kfree(region);
}
-int svm_unregister_enc_region(struct kvm *kvm,
- struct kvm_enc_region *range)
+int sev_mem_enc_unregister_region(struct kvm *kvm,
+ struct kvm_enc_region *range)
{
struct enc_region *region;
int ret;
@@ -1972,7 +1992,7 @@ failed:
return ret;
}
-int svm_vm_copy_asid_from(struct kvm *kvm, unsigned int source_fd)
+int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd)
{
struct file *source_kvm_file;
struct kvm *source_kvm;
@@ -2008,10 +2028,10 @@ int svm_vm_copy_asid_from(struct kvm *kvm, unsigned int source_fd)
*/
source_sev = &to_kvm_svm(source_kvm)->sev_info;
kvm_get_kvm(source_kvm);
- source_sev->num_mirrored_vms++;
+ mirror_sev = &to_kvm_svm(kvm)->sev_info;
+ list_add_tail(&mirror_sev->mirror_entry, &source_sev->mirror_vms);
/* Set enc_context_owner and copy its encryption context over */
- mirror_sev = &to_kvm_svm(kvm)->sev_info;
mirror_sev->enc_context_owner = source_kvm;
mirror_sev->active = true;
mirror_sev->asid = source_sev->asid;
@@ -2019,6 +2039,7 @@ int svm_vm_copy_asid_from(struct kvm *kvm, unsigned int source_fd)
mirror_sev->es_active = source_sev->es_active;
mirror_sev->handle = source_sev->handle;
INIT_LIST_HEAD(&mirror_sev->regions_list);
+ INIT_LIST_HEAD(&mirror_sev->mirror_vms);
ret = 0;
/*
@@ -2041,19 +2062,17 @@ void sev_vm_destroy(struct kvm *kvm)
struct list_head *head = &sev->regions_list;
struct list_head *pos, *q;
- WARN_ON(sev->num_mirrored_vms);
-
if (!sev_guest(kvm))
return;
+ WARN_ON(!list_empty(&sev->mirror_vms));
+
/* If this is a mirror_kvm release the enc_context_owner and skip sev cleanup */
if (is_mirroring_enc_context(kvm)) {
struct kvm *owner_kvm = sev->enc_context_owner;
- struct kvm_sev_info *owner_sev = &to_kvm_svm(owner_kvm)->sev_info;
mutex_lock(&owner_kvm->lock);
- if (!WARN_ON(!owner_sev->num_mirrored_vms))
- owner_sev->num_mirrored_vms--;
+ list_del(&sev->mirror_entry);
mutex_unlock(&owner_kvm->lock);
kvm_put_kvm(owner_kvm);
return;
@@ -2173,7 +2192,7 @@ out:
#endif
}
-void sev_hardware_teardown(void)
+void sev_hardware_unsetup(void)
{
if (!sev_enabled)
return;
@@ -2358,7 +2377,7 @@ static void sev_es_sync_from_ghcb(struct vcpu_svm *svm)
memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap));
}
-static bool sev_es_validate_vmgexit(struct vcpu_svm *svm)
+static int sev_es_validate_vmgexit(struct vcpu_svm *svm)
{
struct kvm_vcpu *vcpu;
struct ghcb *ghcb;
@@ -2463,7 +2482,7 @@ static bool sev_es_validate_vmgexit(struct vcpu_svm *svm)
goto vmgexit_err;
}
- return true;
+ return 0;
vmgexit_err:
vcpu = &svm->vcpu;
@@ -2486,7 +2505,8 @@ vmgexit_err:
ghcb_set_sw_exit_info_1(ghcb, 2);
ghcb_set_sw_exit_info_2(ghcb, reason);
- return false;
+ /* Resume the guest to "return" the error code. */
+ return 1;
}
void sev_es_unmap_ghcb(struct vcpu_svm *svm)
@@ -2545,7 +2565,7 @@ void pre_sev_run(struct vcpu_svm *svm, int cpu)
}
#define GHCB_SCRATCH_AREA_LIMIT (16ULL * PAGE_SIZE)
-static bool setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len)
+static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len)
{
struct vmcb_control_area *control = &svm->vmcb->control;
struct ghcb *ghcb = svm->sev_es.ghcb;
@@ -2598,14 +2618,14 @@ static bool setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len)
}
scratch_va = kvzalloc(len, GFP_KERNEL_ACCOUNT);
if (!scratch_va)
- goto e_scratch;
+ return -ENOMEM;
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");
kvfree(scratch_va);
- goto e_scratch;
+ return -EFAULT;
}
/*
@@ -2621,13 +2641,13 @@ static bool setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len)
svm->sev_es.ghcb_sa = scratch_va;
svm->sev_es.ghcb_sa_len = len;
- return true;
+ return 0;
e_scratch:
ghcb_set_sw_exit_info_1(ghcb, 2);
ghcb_set_sw_exit_info_2(ghcb, GHCB_ERR_INVALID_SCRATCH_AREA);
- return false;
+ return 1;
}
static void set_ghcb_msr_bits(struct vcpu_svm *svm, u64 value, u64 mask,
@@ -2765,17 +2785,18 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu)
exit_code = ghcb_get_sw_exit_code(ghcb);
- if (!sev_es_validate_vmgexit(svm))
- return 1;
+ 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 = 1;
switch (exit_code) {
case SVM_VMGEXIT_MMIO_READ:
- if (!setup_vmgexit_scratch(svm, true, control->exit_info_2))
+ ret = setup_vmgexit_scratch(svm, true, control->exit_info_2);
+ if (ret)
break;
ret = kvm_sev_es_mmio_read(vcpu,
@@ -2784,7 +2805,8 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu)
svm->sev_es.ghcb_sa);
break;
case SVM_VMGEXIT_MMIO_WRITE:
- if (!setup_vmgexit_scratch(svm, false, control->exit_info_2))
+ ret = setup_vmgexit_scratch(svm, false, control->exit_info_2);
+ if (ret)
break;
ret = kvm_sev_es_mmio_write(vcpu,
@@ -2817,6 +2839,7 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu)
ghcb_set_sw_exit_info_2(ghcb, GHCB_ERR_INVALID_INPUT);
}
+ ret = 1;
break;
}
case SVM_VMGEXIT_UNSUPPORTED_EVENT:
@@ -2836,6 +2859,7 @@ int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in)
{
int count;
int bytes;
+ int r;
if (svm->vmcb->control.exit_info_2 > INT_MAX)
return -EINVAL;
@@ -2844,8 +2868,9 @@ int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in)
if (unlikely(check_mul_overflow(count, size, &bytes)))
return -EINVAL;
- if (!setup_vmgexit_scratch(svm, in, bytes))
- return 1;
+ r = setup_vmgexit_scratch(svm, in, bytes);
+ if (r)
+ return r;
return kvm_sev_es_string_io(&svm->vcpu, size, port, svm->sev_es.ghcb_sa,
count, in);
@@ -2907,20 +2932,16 @@ void sev_es_vcpu_reset(struct vcpu_svm *svm)
sev_enc_bit));
}
-void sev_es_prepare_guest_switch(struct vcpu_svm *svm, unsigned int cpu)
+void sev_es_prepare_switch_to_guest(struct vmcb_save_area *hostsa)
{
- struct svm_cpu_data *sd = per_cpu(svm_data, cpu);
- struct vmcb_save_area *hostsa;
-
/*
* 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.
+ * of which one step is to perform a VMLOAD. KVM performs the
+ * corresponding VMSAVE in svm_prepare_guest_switch for both
+ * traditional and SEV-ES guests.
*/
- vmsave(__sme_page_pa(sd->save_area));
/* 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 current host value */