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authorLinus Torvalds <torvalds@linux-foundation.org>2021-03-19 14:10:07 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-03-19 14:10:07 -0700
commitecd8ee7f9c1af253738ca4321509ddee727d468d (patch)
treeb683a542f68c52000db681b4886c87c14fea7580
parent3149860dc717e8dd339d89d17ebe615cb09e158b (diff)
parent9ce3746d64132a561bceab6421715e7c04e85074 (diff)
downloadlinux-stericsson-ecd8ee7f9c1af253738ca4321509ddee727d468d.tar.gz
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini: "Fixes for kvm on x86: - new selftests - fixes for migration with HyperV re-enlightenment enabled - fix RCU/SRCU usage - fixes for local_irq_restore misuse false positive" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: documentation/kvm: additional explanations on KVM_SET_BOOT_CPU_ID x86/kvm: Fix broken irq restoration in kvm_wait KVM: X86: Fix missing local pCPU when executing wbinvd on all dirty pCPUs KVM: x86: Protect userspace MSR filter with SRCU, and set atomically-ish selftests: kvm: add set_boot_cpu_id test selftests: kvm: add _vm_ioctl selftests: kvm: add get_msr_index_features selftests: kvm: Add basic Hyper-V clocksources tests KVM: x86: hyper-v: Don't touch TSC page values when guest opted for re-enlightenment KVM: x86: hyper-v: Track Hyper-V TSC page status KVM: x86: hyper-v: Prevent using not-yet-updated TSC page by secondary CPUs KVM: x86: hyper-v: Limit guest to writing zero to HV_X64_MSR_TSC_EMULATION_STATUS KVM: x86/mmu: Store the address space ID in the TDP iterator KVM: x86/mmu: Factor out tdp_iter_return_to_root KVM: x86/mmu: Fix RCU usage when atomically zapping SPTEs KVM: x86/mmu: Fix RCU usage in handle_removed_tdp_mmu_page
-rw-r--r--Documentation/virt/kvm/api.rst9
-rw-r--r--arch/x86/include/asm/kvm_host.h34
-rw-r--r--arch/x86/kernel/kvm.c23
-rw-r--r--arch/x86/kvm/hyperv.c91
-rw-r--r--arch/x86/kvm/hyperv.h1
-rw-r--r--arch/x86/kvm/mmu/mmu_internal.h5
-rw-r--r--arch/x86/kvm/mmu/tdp_iter.c30
-rw-r--r--arch/x86/kvm/mmu/tdp_iter.h4
-rw-r--r--arch/x86/kvm/mmu/tdp_mmu.c40
-rw-r--r--arch/x86/kvm/x86.c113
-rw-r--r--tools/testing/selftests/kvm/.gitignore3
-rw-r--r--tools/testing/selftests/kvm/Makefile3
-rw-r--r--tools/testing/selftests/kvm/include/kvm_util.h2
-rw-r--r--tools/testing/selftests/kvm/lib/kvm_util.c7
-rw-r--r--tools/testing/selftests/kvm/lib/kvm_util_internal.h2
-rw-r--r--tools/testing/selftests/kvm/x86_64/get_msr_index_features.c134
-rw-r--r--tools/testing/selftests/kvm/x86_64/hyperv_clock.c260
-rw-r--r--tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c166
18 files changed, 807 insertions, 120 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index 38e327d4b479..307f2fcf1b02 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -1495,7 +1495,8 @@ Fails if any VCPU has already been created.
Define which vcpu is the Bootstrap Processor (BSP). Values are the same
as the vcpu id in KVM_CREATE_VCPU. If this ioctl is not called, the default
-is vcpu 0.
+is vcpu 0. This ioctl has to be called before vcpu creation,
+otherwise it will return EBUSY error.
4.42 KVM_GET_XSAVE
@@ -4806,8 +4807,10 @@ If an MSR access is not permitted through the filtering, it generates a
allows user space to deflect and potentially handle various MSR accesses
into user space.
-If a vCPU is in running state while this ioctl is invoked, the vCPU may
-experience inconsistent filtering behavior on MSR accesses.
+Note, invoking this ioctl with a vCPU is running is inherently racy. However,
+KVM does guarantee that vCPUs will see either the previous filter or the new
+filter, e.g. MSRs with identical settings in both the old and new filter will
+have deterministic behavior.
4.127 KVM_XEN_HVM_SET_ATTR
--------------------------
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 9bc091ecaaeb..3768819693e5 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -884,12 +884,29 @@ struct kvm_hv_syndbg {
u64 options;
};
+/* Current state of Hyper-V TSC page clocksource */
+enum hv_tsc_page_status {
+ /* TSC page was not set up or disabled */
+ HV_TSC_PAGE_UNSET = 0,
+ /* TSC page MSR was written by the guest, update pending */
+ HV_TSC_PAGE_GUEST_CHANGED,
+ /* TSC page MSR was written by KVM userspace, update pending */
+ HV_TSC_PAGE_HOST_CHANGED,
+ /* TSC page was properly set up and is currently active */
+ HV_TSC_PAGE_SET,
+ /* TSC page is currently being updated and therefore is inactive */
+ HV_TSC_PAGE_UPDATING,
+ /* TSC page was set up with an inaccessible GPA */
+ HV_TSC_PAGE_BROKEN,
+};
+
/* Hyper-V emulation context */
struct kvm_hv {
struct mutex hv_lock;
u64 hv_guest_os_id;
u64 hv_hypercall;
u64 hv_tsc_page;
+ enum hv_tsc_page_status hv_tsc_page_status;
/* Hyper-v based guest crash (NT kernel bugcheck) parameters */
u64 hv_crash_param[HV_X64_MSR_CRASH_PARAMS];
@@ -931,6 +948,12 @@ enum kvm_irqchip_mode {
KVM_IRQCHIP_SPLIT, /* created with KVM_CAP_SPLIT_IRQCHIP */
};
+struct kvm_x86_msr_filter {
+ u8 count;
+ bool default_allow:1;
+ struct msr_bitmap_range ranges[16];
+};
+
#define APICV_INHIBIT_REASON_DISABLE 0
#define APICV_INHIBIT_REASON_HYPERV 1
#define APICV_INHIBIT_REASON_NESTED 2
@@ -1025,16 +1048,11 @@ struct kvm_arch {
bool guest_can_read_msr_platform_info;
bool exception_payload_enabled;
+ bool bus_lock_detection_enabled;
+
/* Deflect RDMSR and WRMSR to user space when they trigger a #GP */
u32 user_space_msr_mask;
-
- struct {
- u8 count;
- bool default_allow:1;
- struct msr_bitmap_range ranges[16];
- } msr_filter;
-
- bool bus_lock_detection_enabled;
+ struct kvm_x86_msr_filter __rcu *msr_filter;
struct kvm_pmu_event_filter __rcu *pmu_event_filter;
struct task_struct *nx_lpage_recovery_thread;
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 5e78e01ca3b4..78bb0fae3982 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -836,28 +836,25 @@ static void kvm_kick_cpu(int cpu)
static void kvm_wait(u8 *ptr, u8 val)
{
- unsigned long flags;
-
if (in_nmi())
return;
- local_irq_save(flags);
-
- if (READ_ONCE(*ptr) != val)
- goto out;
-
/*
* halt until it's our turn and kicked. Note that we do safe halt
* for irq enabled case to avoid hang when lock info is overwritten
* in irq spinlock slowpath and no spurious interrupt occur to save us.
*/
- if (arch_irqs_disabled_flags(flags))
- halt();
- else
- safe_halt();
+ if (irqs_disabled()) {
+ if (READ_ONCE(*ptr) == val)
+ halt();
+ } else {
+ local_irq_disable();
-out:
- local_irq_restore(flags);
+ if (READ_ONCE(*ptr) == val)
+ safe_halt();
+
+ local_irq_enable();
+ }
}
#ifdef CONFIG_X86_32
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 58fa8c029867..f98370a39936 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -520,10 +520,10 @@ static u64 get_time_ref_counter(struct kvm *kvm)
u64 tsc;
/*
- * The guest has not set up the TSC page or the clock isn't
- * stable, fall back to get_kvmclock_ns.
+ * Fall back to get_kvmclock_ns() when TSC page hasn't been set up,
+ * is broken, disabled or being updated.
*/
- if (!hv->tsc_ref.tsc_sequence)
+ if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET)
return div_u64(get_kvmclock_ns(kvm), 100);
vcpu = kvm_get_vcpu(kvm, 0);
@@ -1077,6 +1077,21 @@ static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
return true;
}
+/*
+ * Don't touch TSC page values if the guest has opted for TSC emulation after
+ * migration. KVM doesn't fully support reenlightenment notifications and TSC
+ * access emulation and Hyper-V is known to expect the values in TSC page to
+ * stay constant before TSC access emulation is disabled from guest side
+ * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC
+ * frequency and guest visible TSC value across migration (and prevent it when
+ * TSC scaling is unsupported).
+ */
+static inline bool tsc_page_update_unsafe(struct kvm_hv *hv)
+{
+ return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) &&
+ hv->hv_tsc_emulation_control;
+}
+
void kvm_hv_setup_tsc_page(struct kvm *kvm,
struct pvclock_vcpu_time_info *hv_clock)
{
@@ -1087,7 +1102,8 @@ void kvm_hv_setup_tsc_page(struct kvm *kvm,
BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
- if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
+ if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
+ hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET)
return;
mutex_lock(&hv->hv_lock);
@@ -1101,7 +1117,15 @@ void kvm_hv_setup_tsc_page(struct kvm *kvm,
*/
if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
&tsc_seq, sizeof(tsc_seq))))
+ goto out_err;
+
+ if (tsc_seq && tsc_page_update_unsafe(hv)) {
+ if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
+ goto out_err;
+
+ hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
goto out_unlock;
+ }
/*
* While we're computing and writing the parameters, force the
@@ -1110,15 +1134,15 @@ void kvm_hv_setup_tsc_page(struct kvm *kvm,
hv->tsc_ref.tsc_sequence = 0;
if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
&hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
- goto out_unlock;
+ goto out_err;
if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
- goto out_unlock;
+ goto out_err;
/* Ensure sequence is zero before writing the rest of the struct. */
smp_wmb();
if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
- goto out_unlock;
+ goto out_err;
/*
* Now switch to the TSC page mechanism by writing the sequence.
@@ -1131,8 +1155,45 @@ void kvm_hv_setup_tsc_page(struct kvm *kvm,
smp_wmb();
hv->tsc_ref.tsc_sequence = tsc_seq;
- kvm_write_guest(kvm, gfn_to_gpa(gfn),
- &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence));
+ if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
+ &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
+ goto out_err;
+
+ hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
+ goto out_unlock;
+
+out_err:
+ hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
+out_unlock:
+ mutex_unlock(&hv->hv_lock);
+}
+
+void kvm_hv_invalidate_tsc_page(struct kvm *kvm)
+{
+ struct kvm_hv *hv = to_kvm_hv(kvm);
+ u64 gfn;
+
+ if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
+ hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET ||
+ tsc_page_update_unsafe(hv))
+ return;
+
+ mutex_lock(&hv->hv_lock);
+
+ if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
+ goto out_unlock;
+
+ /* Preserve HV_TSC_PAGE_GUEST_CHANGED/HV_TSC_PAGE_HOST_CHANGED states */
+ if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET)
+ hv->hv_tsc_page_status = HV_TSC_PAGE_UPDATING;
+
+ gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
+
+ hv->tsc_ref.tsc_sequence = 0;
+ if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
+ &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
+ hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
+
out_unlock:
mutex_unlock(&hv->hv_lock);
}
@@ -1193,8 +1254,15 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
}
case HV_X64_MSR_REFERENCE_TSC:
hv->hv_tsc_page = data;
- if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE)
+ if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) {
+ if (!host)
+ hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED;
+ else
+ hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
+ } else {
+ hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET;
+ }
break;
case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
return kvm_hv_msr_set_crash_data(kvm,
@@ -1229,6 +1297,9 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
hv->hv_tsc_emulation_control = data;
break;
case HV_X64_MSR_TSC_EMULATION_STATUS:
+ if (data && !host)
+ return 1;
+
hv->hv_tsc_emulation_status = data;
break;
case HV_X64_MSR_TIME_REF_COUNT:
diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index e951af1fcb2c..60547d5cb6d7 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -133,6 +133,7 @@ void kvm_hv_process_stimers(struct kvm_vcpu *vcpu);
void kvm_hv_setup_tsc_page(struct kvm *kvm,
struct pvclock_vcpu_time_info *hv_clock);
+void kvm_hv_invalidate_tsc_page(struct kvm *kvm);
void kvm_hv_init_vm(struct kvm *kvm);
void kvm_hv_destroy_vm(struct kvm *kvm);
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index ec4fc28b325a..1f6f98c76bdf 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -78,6 +78,11 @@ static inline struct kvm_mmu_page *sptep_to_sp(u64 *sptep)
return to_shadow_page(__pa(sptep));
}
+static inline int kvm_mmu_page_as_id(struct kvm_mmu_page *sp)
+{
+ return sp->role.smm ? 1 : 0;
+}
+
static inline bool kvm_vcpu_ad_need_write_protect(struct kvm_vcpu *vcpu)
{
/*
diff --git a/arch/x86/kvm/mmu/tdp_iter.c b/arch/x86/kvm/mmu/tdp_iter.c
index e5f148106e20..b3ed302c1a35 100644
--- a/arch/x86/kvm/mmu/tdp_iter.c
+++ b/arch/x86/kvm/mmu/tdp_iter.c
@@ -21,6 +21,21 @@ static gfn_t round_gfn_for_level(gfn_t gfn, int level)
}
/*
+ * Return the TDP iterator to the root PT and allow it to continue its
+ * traversal over the paging structure from there.
+ */
+void tdp_iter_restart(struct tdp_iter *iter)
+{
+ iter->yielded_gfn = iter->next_last_level_gfn;
+ iter->level = iter->root_level;
+
+ iter->gfn = round_gfn_for_level(iter->next_last_level_gfn, iter->level);
+ tdp_iter_refresh_sptep(iter);
+
+ iter->valid = true;
+}
+
+/*
* Sets a TDP iterator to walk a pre-order traversal of the paging structure
* rooted at root_pt, starting with the walk to translate next_last_level_gfn.
*/
@@ -31,16 +46,12 @@ void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level,
WARN_ON(root_level > PT64_ROOT_MAX_LEVEL);
iter->next_last_level_gfn = next_last_level_gfn;
- iter->yielded_gfn = iter->next_last_level_gfn;
iter->root_level = root_level;
iter->min_level = min_level;
- iter->level = root_level;
- iter->pt_path[iter->level - 1] = (tdp_ptep_t)root_pt;
-
- iter->gfn = round_gfn_for_level(iter->next_last_level_gfn, iter->level);
- tdp_iter_refresh_sptep(iter);
+ iter->pt_path[iter->root_level - 1] = (tdp_ptep_t)root_pt;
+ iter->as_id = kvm_mmu_page_as_id(sptep_to_sp(root_pt));
- iter->valid = true;
+ tdp_iter_restart(iter);
}
/*
@@ -159,8 +170,3 @@ void tdp_iter_next(struct tdp_iter *iter)
iter->valid = false;
}
-tdp_ptep_t tdp_iter_root_pt(struct tdp_iter *iter)
-{
- return iter->pt_path[iter->root_level - 1];
-}
-
diff --git a/arch/x86/kvm/mmu/tdp_iter.h b/arch/x86/kvm/mmu/tdp_iter.h
index 4cc177d75c4a..b1748b988d3a 100644
--- a/arch/x86/kvm/mmu/tdp_iter.h
+++ b/arch/x86/kvm/mmu/tdp_iter.h
@@ -36,6 +36,8 @@ struct tdp_iter {
int min_level;
/* The iterator's current level within the paging structure */
int level;
+ /* The address space ID, i.e. SMM vs. regular. */
+ int as_id;
/* A snapshot of the value at sptep */
u64 old_spte;
/*
@@ -62,6 +64,6 @@ tdp_ptep_t spte_to_child_pt(u64 pte, int level);
void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level,
int min_level, gfn_t next_last_level_gfn);
void tdp_iter_next(struct tdp_iter *iter);
-tdp_ptep_t tdp_iter_root_pt(struct tdp_iter *iter);
+void tdp_iter_restart(struct tdp_iter *iter);
#endif /* __KVM_X86_MMU_TDP_ITER_H */
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index d78915019b08..462b1f71c77f 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -203,11 +203,6 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
u64 old_spte, u64 new_spte, int level,
bool shared);
-static int kvm_mmu_page_as_id(struct kvm_mmu_page *sp)
-{
- return sp->role.smm ? 1 : 0;
-}
-
static void handle_changed_spte_acc_track(u64 old_spte, u64 new_spte, int level)
{
bool pfn_changed = spte_to_pfn(old_spte) != spte_to_pfn(new_spte);
@@ -301,11 +296,16 @@ static void tdp_mmu_unlink_page(struct kvm *kvm, struct kvm_mmu_page *sp,
*
* Given a page table that has been removed from the TDP paging structure,
* iterates through the page table to clear SPTEs and free child page tables.
+ *
+ * Note that pt is passed in as a tdp_ptep_t, but it does not need RCU
+ * protection. Since this thread removed it from the paging structure,
+ * this thread will be responsible for ensuring the page is freed. Hence the
+ * early rcu_dereferences in the function.
*/
-static void handle_removed_tdp_mmu_page(struct kvm *kvm, u64 *pt,
+static void handle_removed_tdp_mmu_page(struct kvm *kvm, tdp_ptep_t pt,
bool shared)
{
- struct kvm_mmu_page *sp = sptep_to_sp(pt);
+ struct kvm_mmu_page *sp = sptep_to_sp(rcu_dereference(pt));
int level = sp->role.level;
gfn_t base_gfn = sp->gfn;
u64 old_child_spte;
@@ -318,7 +318,7 @@ static void handle_removed_tdp_mmu_page(struct kvm *kvm, u64 *pt,
tdp_mmu_unlink_page(kvm, sp, shared);
for (i = 0; i < PT64_ENT_PER_PAGE; i++) {
- sptep = pt + i;
+ sptep = rcu_dereference(pt) + i;
gfn = base_gfn + (i * KVM_PAGES_PER_HPAGE(level - 1));
if (shared) {
@@ -492,10 +492,6 @@ static inline bool tdp_mmu_set_spte_atomic(struct kvm *kvm,
struct tdp_iter *iter,
u64 new_spte)
{
- u64 *root_pt = tdp_iter_root_pt(iter);
- struct kvm_mmu_page *root = sptep_to_sp(root_pt);
- int as_id = kvm_mmu_page_as_id(root);
-
lockdep_assert_held_read(&kvm->mmu_lock);
/*
@@ -509,8 +505,8 @@ static inline bool tdp_mmu_set_spte_atomic(struct kvm *kvm,
new_spte) != iter->old_spte)
return false;
- handle_changed_spte(kvm, as_id, iter->gfn, iter->old_spte, new_spte,
- iter->level, true);
+ handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte,
+ new_spte, iter->level, true);
return true;
}
@@ -538,7 +534,7 @@ static inline bool tdp_mmu_zap_spte_atomic(struct kvm *kvm,
* here since the SPTE is going from non-present
* to non-present.
*/
- WRITE_ONCE(*iter->sptep, 0);
+ WRITE_ONCE(*rcu_dereference(iter->sptep), 0);
return true;
}
@@ -564,10 +560,6 @@ static inline void __tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter,
u64 new_spte, bool record_acc_track,
bool record_dirty_log)
{
- tdp_ptep_t root_pt = tdp_iter_root_pt(iter);
- struct kvm_mmu_page *root = sptep_to_sp(root_pt);
- int as_id = kvm_mmu_page_as_id(root);
-
lockdep_assert_held_write(&kvm->mmu_lock);
/*
@@ -581,13 +573,13 @@ static inline void __tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter,
WRITE_ONCE(*rcu_dereference(iter->sptep), new_spte);
- __handle_changed_spte(kvm, as_id, iter->gfn, iter->old_spte, new_spte,
- iter->level, false);
+ __handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte,
+ new_spte, iter->level, false);
if (record_acc_track)
handle_changed_spte_acc_track(iter->old_spte, new_spte,
iter->level);
if (record_dirty_log)
- handle_changed_spte_dirty_log(kvm, as_id, iter->gfn,
+ handle_changed_spte_dirty_log(kvm, iter->as_id, iter->gfn,
iter->old_spte, new_spte,
iter->level);
}
@@ -659,9 +651,7 @@ static inline bool tdp_mmu_iter_cond_resched(struct kvm *kvm,
WARN_ON(iter->gfn > iter->next_last_level_gfn);
- tdp_iter_start(iter, iter->pt_path[iter->root_level - 1],
- iter->root_level, iter->min_level,
- iter->next_last_level_gfn);
+ tdp_iter_restart(iter);
return true;
}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 47e021bdcc94..fe806e894212 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1526,35 +1526,44 @@ EXPORT_SYMBOL_GPL(kvm_enable_efer_bits);
bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type)
{
+ struct kvm_x86_msr_filter *msr_filter;
+ struct msr_bitmap_range *ranges;
struct kvm *kvm = vcpu->kvm;
- struct msr_bitmap_range *ranges = kvm->arch.msr_filter.ranges;
- u32 count = kvm->arch.msr_filter.count;
- u32 i;
- bool r = kvm->arch.msr_filter.default_allow;
+ bool allowed;
int idx;
+ u32 i;
- /* MSR filtering not set up or x2APIC enabled, allow everything */
- if (!count || (index >= 0x800 && index <= 0x8ff))
+ /* x2APIC MSRs do not support filtering. */
+ if (index >= 0x800 && index <= 0x8ff)
return true;
- /* Prevent collision with set_msr_filter */
idx = srcu_read_lock(&kvm->srcu);
- for (i = 0; i < count; i++) {
+ msr_filter = srcu_dereference(kvm->arch.msr_filter, &kvm->srcu);
+ if (!msr_filter) {
+ allowed = true;
+ goto out;
+ }
+
+ allowed = msr_filter->default_allow;
+ ranges = msr_filter->ranges;
+
+ for (i = 0; i < msr_filter->count; i++) {
u32 start = ranges[i].base;
u32 end = start + ranges[i].nmsrs;
u32 flags = ranges[i].flags;
unsigned long *bitmap = ranges[i].bitmap;
if ((index >= start) && (index < end) && (flags & type)) {
- r = !!test_bit(index - start, bitmap);
+ allowed = !!test_bit(index - start, bitmap);
break;
}
}
+out:
srcu_read_unlock(&kvm->srcu, idx);
- return r;
+ return allowed;
}
EXPORT_SYMBOL_GPL(kvm_msr_allowed);
@@ -2551,6 +2560,8 @@ static void kvm_gen_update_masterclock(struct kvm *kvm)
struct kvm_vcpu *vcpu;
struct kvm_arch *ka = &kvm->arch;
+ kvm_hv_invalidate_tsc_page(kvm);
+
spin_lock(&ka->pvclock_gtod_sync_lock);
kvm_make_mclock_inprogress_request(kvm);
/* no guest entries from this point */
@@ -5352,25 +5363,34 @@ split_irqchip_unlock:
return r;
}
-static void kvm_clear_msr_filter(struct kvm *kvm)
+static struct kvm_x86_msr_filter *kvm_alloc_msr_filter(bool default_allow)
+{
+ struct kvm_x86_msr_filter *msr_filter;
+
+ msr_filter = kzalloc(sizeof(*msr_filter), GFP_KERNEL_ACCOUNT);
+ if (!msr_filter)
+ return NULL;
+
+ msr_filter->default_allow = default_allow;
+ return msr_filter;
+}
+
+static void kvm_free_msr_filter(struct kvm_x86_msr_filter *msr_filter)
{
u32 i;
- u32 count = kvm->arch.msr_filter.count;
- struct msr_bitmap_range ranges[16];
- mutex_lock(&kvm->lock);
- kvm->arch.msr_filter.count = 0;
- memcpy(ranges, kvm->arch.msr_filter.ranges, count * sizeof(ranges[0]));
- mutex_unlock(&kvm->lock);
- synchronize_srcu(&kvm->srcu);
+ if (!msr_filter)
+ return;
- for (i = 0; i < count; i++)
- kfree(ranges[i].bitmap);
+ for (i = 0; i < msr_filter->count; i++)
+ kfree(msr_filter->ranges[i].bitmap);
+
+ kfree(msr_filter);
}
-static int kvm_add_msr_filter(struct kvm *kvm, struct kvm_msr_filter_range *user_range)
+static int kvm_add_msr_filter(struct kvm_x86_msr_filter *msr_filter,
+ struct kvm_msr_filter_range *user_range)
{
- struct msr_bitmap_range *ranges = kvm->arch.msr_filter.ranges;
struct msr_bitmap_range range;
unsigned long *bitmap = NULL;
size_t bitmap_size;
@@ -5404,11 +5424,9 @@ static int kvm_add_msr_filter(struct kvm *kvm, struct kvm_msr_filter_range *user
goto err;
}
- /* Everything ok, add this range identifier to our global pool */
- ranges[kvm->arch.msr_filter.count] = range;
- /* Make sure we filled the array before we tell anyone to walk it */
- smp_wmb();
- kvm->arch.msr_filter.count++;
+ /* Everything ok, add this range identifier. */
+ msr_filter->ranges[msr_filter->count] = range;
+ msr_filter->count++;
return 0;
err:
@@ -5419,10 +5437,11 @@ err:
static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm, void __user *argp)
{
struct kvm_msr_filter __user *user_msr_filter = argp;
+ struct kvm_x86_msr_filter *new_filter, *old_filter;
struct kvm_msr_filter filter;
bool default_allow;
- int r = 0;
bool empty = true;
+ int r = 0;
u32 i;
if (copy_from_user(&filter, user_msr_filter, sizeof(filter)))
@@ -5435,25 +5454,32 @@ static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm, void __user *argp)
if (empty && !default_allow)
return -EINVAL;
- kvm_clear_msr_filter(kvm);
-
- kvm->arch.msr_filter.default_allow = default_allow;
+ new_filter = kvm_alloc_msr_filter(default_allow);
+ if (!new_filter)
+ return -ENOMEM;
- /*
- * Protect from concurrent calls to this function that could trigger
- * a TOCTOU violation on kvm->arch.msr_filter.count.
- */
- mutex_lock(&kvm->lock);
for (i = 0; i < ARRAY_SIZE(filter.ranges); i++) {
- r = kvm_add_msr_filter(kvm, &filter.ranges[i]);
- if (r)
- break;
+ r = kvm_add_msr_filter(new_filter, &filter.ranges[i]);
+ if (r) {
+ kvm_free_msr_filter(new_filter);
+ return r;
+ }
}
+ mutex_lock(&kvm->lock);
+
+ /* The per-VM filter is protected by kvm->lock... */
+ old_filter = srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1);
+
+ rcu_assign_pointer(kvm->arch.msr_filter, new_filter);
+ synchronize_srcu(&kvm->srcu);
+
+ kvm_free_msr_filter(old_filter);
+
kvm_make_all_cpus_request(kvm, KVM_REQ_MSR_FILTER_CHANGED);
mutex_unlock(&kvm->lock);
- return r;
+ return 0;
}
long kvm_arch_vm_ioctl(struct file *filp,
@@ -6603,7 +6629,7 @@ static int kvm_emulate_wbinvd_noskip(struct kvm_vcpu *vcpu)
int cpu = get_cpu();
cpumask_set_cpu(cpu, vcpu->arch.wbinvd_dirty_mask);
- smp_call_function_many(vcpu->arch.wbinvd_dirty_mask,
+ on_each_cpu_mask(vcpu->arch.wbinvd_dirty_mask,
wbinvd_ipi, NULL, 1);
put_cpu();
cpumask_clear(vcpu->arch.wbinvd_dirty_mask);
@@ -10634,8 +10660,6 @@ void kvm_arch_pre_destroy_vm(struct kvm *kvm)
void kvm_arch_destroy_vm(struct kvm *kvm)
{
- u32 i;
-
if (current->mm == kvm->mm) {
/*
* Free memory regions allocated on behalf of userspace,
@@ -10651,8 +10675,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
mutex_unlock(&kvm->slots_lock);
}
static_call_cond(kvm_x86_vm_destroy)(kvm);
- for (i = 0; i < kvm->arch.msr_filter.count; i++)
- kfree(kvm->arch.msr_filter.ranges[i].bitmap);
+ kvm_free_msr_filter(srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1));
kvm_pic_destroy(kvm);
kvm_ioapic_destroy(kvm);
kvm_free_vcpus(kvm);
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 32b87cc77c8e..7bd7e776c266 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -8,10 +8,13 @@
/x86_64/debug_regs
/x86_64/evmcs_test
/x86_64/get_cpuid_test
+/x86_64/get_msr_index_features
/x86_64/kvm_pv_test
+/x86_64/hyperv_clock
/x86_64/hyperv_cpuid
/x86_64/mmio_warning_test
/x86_64/platform_info_test
+/x86_64/set_boot_cpu_id
/x86_64/set_sregs_test
/x86_64/smm_test
/x86_64/state_test
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index a6d61f451f88..67eebb53235f 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -39,12 +39,15 @@ LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c
LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test
+TEST_GEN_PROGS_x86_64 += x86_64/get_msr_index_features
TEST_GEN_PROGS_x86_64 += x86_64/evmcs_test
TEST_GEN_PROGS_x86_64 += x86_64/get_cpuid_test
+TEST_GEN_PROGS_x86_64 += x86_64/hyperv_clock
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid
TEST_GEN_PROGS_x86_64 += x86_64/kvm_pv_test
TEST_GEN_PROGS_x86_64 += x86_64/mmio_warning_test
TEST_GEN_PROGS_x86_64 += x86_64/platform_info_test
+TEST_GEN_PROGS_x86_64 += x86_64/set_boot_cpu_id
TEST_GEN_PROGS_x86_64 += x86_64/set_sregs_test
TEST_GEN_PROGS_x86_64 += x86_64/smm_test
TEST_GEN_PROGS_x86_64 += x86_64/state_test
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 2d7eb6989e83..0f4258eaa629 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -16,6 +16,7 @@
#include "sparsebit.h"
+#define KVM_DEV_PATH "/dev/kvm"
#define KVM_MAX_VCPUS 512
/*
@@ -133,6 +134,7 @@ void vcpu_ioctl(struct kvm_vm *vm, uint32_t vcpuid, unsigned long ioctl,
int _vcpu_ioctl(struct kvm_vm *vm, uint32_t vcpuid, unsigned long ioctl,
void *arg);
void vm_ioctl(struct kvm_vm *vm, unsigned long ioctl, void *arg);
+int _vm_ioctl(struct kvm_vm *vm, unsigned long cmd, void *arg);
void kvm_ioctl(struct kvm_vm *vm, unsigned long ioctl, void *arg);
int _kvm_ioctl(struct kvm_vm *vm, unsigned long ioctl, void *arg);
void vm_mem_region_set_flags(struct kvm_vm *vm, uint32_t slot, uint32_t flags);
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index e5fbf16f725b..b8849a1aca79 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1697,11 +1697,16 @@ void vm_ioctl(struct kvm_vm *vm, unsigned long cmd, void *arg)
{
int ret;
- ret = ioctl(vm->fd, cmd, arg);
+ ret = _vm_ioctl(vm, cmd, arg);
TEST_ASSERT(ret == 0, "vm ioctl %lu failed, rc: %i errno: %i (%s)",
cmd, ret, errno, strerror(errno));
}
+int _vm_ioctl(struct kvm_vm *vm, unsigned long cmd, void *arg)
+{
+ return ioctl(vm->fd, cmd, arg);
+}
+
/*
* KVM system ioctl
*
diff --git a/tools/testing/selftests/kvm/lib/kvm_util_internal.h b/tools/testing/selftests/kvm/lib/kvm_util_internal.h
index 34465dc562d8..91ce1b5d480b 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util_internal.h
+++ b/tools/testing/selftests/kvm/lib/kvm_util_internal.h
@@ -10,8 +10,6 @@
#include "sparsebit.h"
-#define KVM_DEV_PATH "/dev/kvm"
-
struct userspace_mem_region {
struct kvm_userspace_memory_region region;
struct sparsebit *unused_phy_pages;
diff --git a/tools/testing/selftests/kvm/x86_64/get_msr_index_features.c b/tools/testing/selftests/kvm/x86_64/get_msr_index_features.c
new file mode 100644
index 000000000000..cb953df4d7d0
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/get_msr_index_features.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Test that KVM_GET_MSR_INDEX_LIST and
+ * KVM_GET_MSR_FEATURE_INDEX_LIST work as intended
+ *
+ * Copyright (C) 2020, Red Hat, Inc.
+ */
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+
+static int kvm_num_index_msrs(int kvm_fd, int nmsrs)
+{
+ struct kvm_msr_list *list;
+ int r;
+
+ list = malloc(sizeof(*list) + nmsrs * sizeof(list->indices[0]));
+ list->nmsrs = nmsrs;
+ r = ioctl(kvm_fd, KVM_GET_MSR_INDEX_LIST, list);
+ TEST_ASSERT(r == -1 && errno == E2BIG,
+ "Unexpected result from KVM_GET_MSR_INDEX_LIST probe, r: %i",
+ r);
+
+ r = list->nmsrs;
+ free(list);
+ return r;
+}
+
+static void test_get_msr_index(void)
+{
+ int old_res, res, kvm_fd, r;
+ struct kvm_msr_list *list;
+
+ kvm_fd = open(KVM_DEV_PATH, O_RDONLY);
+ if (kvm_fd < 0)
+ exit(KSFT_SKIP);
+
+ old_res = kvm_num_index_msrs(kvm_fd, 0);
+ TEST_ASSERT(old_res != 0, "Expecting nmsrs to be > 0");
+
+ if (old_res != 1) {
+ res = kvm_num_index_msrs(kvm_fd, 1);
+ TEST_ASSERT(res > 1, "Expecting nmsrs to be > 1");
+ TEST_ASSERT(res == old_res, "Expecting nmsrs to be identical");
+ }
+
+ list = malloc(sizeof(*list) + old_res * sizeof(list->indices[0]));
+ list->nmsrs = old_res;
+ r = ioctl(kvm_fd, KVM_GET_MSR_INDEX_LIST, list);
+
+ TEST_ASSERT(r == 0,
+ "Unexpected result from KVM_GET_MSR_FEATURE_INDEX_LIST, r: %i",
+ r);
+ TEST_ASSERT(list->nmsrs == old_res, "Expecting nmsrs to be identical");
+ free(list);
+
+ close(kvm_fd);
+}
+
+static int kvm_num_feature_msrs(int kvm_fd, int nmsrs)
+{
+ struct kvm_msr_list *list;
+ int r;
+
+ list = malloc(sizeof(*list) + nmsrs * sizeof(list->indices[0]));
+ list->nmsrs = nmsrs;
+ r = ioctl(kvm_fd, KVM_GET_MSR_FEATURE_INDEX_LIST, list);
+ TEST_ASSERT(r == -1 && errno == E2BIG,
+ "Unexpected result from KVM_GET_MSR_FEATURE_INDEX_LIST probe, r: %i",
+ r);
+
+ r = list->nmsrs;
+ free(list);
+ return r;
+}
+
+struct kvm_msr_list *kvm_get_msr_feature_list(int kvm_fd, int nmsrs)
+{
+ struct kvm_msr_list *list;
+ int r;
+
+ list = malloc(sizeof(*list) + nmsrs * sizeof(list->indices[0]));
+ list->nmsrs = nmsrs;
+ r = ioctl(kvm_fd, KVM_GET_MSR_FEATURE_INDEX_LIST, list);
+
+ TEST_ASSERT(r == 0,
+ "Unexpected result from KVM_GET_MSR_FEATURE_INDEX_LIST, r: %i",
+ r);
+
+ return list;
+}
+
+static void test_get_msr_feature(void)
+{
+ int res, old_res, i, kvm_fd;
+ struct kvm_msr_list *feature_list;
+
+ kvm_fd = open(KVM_DEV_PATH, O_RDONLY);
+ if (kvm_fd < 0)
+ exit(KSFT_SKIP);
+
+ old_res = kvm_num_feature_msrs(kvm_fd, 0);
+ TEST_ASSERT(old_res != 0, "Expecting nmsrs to be > 0");
+
+ if (old_res != 1) {
+ res = kvm_num_feature_msrs(kvm_fd, 1);
+ TEST_ASSERT(res > 1, "Expecting nmsrs to be > 1");
+ TEST_ASSERT(res == old_res, "Expecting nmsrs to be identical");
+ }
+
+ feature_list = kvm_get_msr_feature_list(kvm_fd, old_res);
+ TEST_ASSERT(old_res == feature_list->nmsrs,
+ "Unmatching number of msr indexes");
+
+ for (i = 0; i < feature_list->nmsrs; i++)
+ kvm_get_feature_msr(feature_list->indices[i]);
+
+ free(feature_list);
+ close(kvm_fd);
+}
+
+int main(int argc, char *argv[])
+{
+ if (kvm_check_cap(KVM_CAP_GET_MSR_FEATURES))
+ test_get_msr_feature();
+
+ test_get_msr_index();
+}
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_clock.c b/tools/testing/selftests/kvm/x86_64/hyperv_clock.c
new file mode 100644
index 000000000000..ffbc4555c6e2
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_clock.c
@@ -0,0 +1,260 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2021, Red Hat, Inc.
+ *
+ * Tests for Hyper-V clocksources
+ */
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+
+struct ms_hyperv_tsc_page {
+ volatile u32 tsc_sequence;
+ u32 reserved1;
+ volatile u64 tsc_scale;
+ volatile s64 tsc_offset;
+} __packed;
+
+#define HV_X64_MSR_GUEST_OS_ID 0x40000000
+#define HV_X64_MSR_TIME_REF_COUNT 0x40000020
+#define HV_X64_MSR_REFERENCE_TSC 0x40000021
+#define HV_X64_MSR_TSC_FREQUENCY 0x40000022
+#define HV_X64_MSR_REENLIGHTENMENT_CONTROL 0x40000106
+#define HV_X64_MSR_TSC_EMULATION_CONTROL 0x40000107
+
+/* Simplified mul_u64_u64_shr() */
+static inline u64 mul_u64_u64_shr64(u64 a, u64 b)
+{
+ union {
+ u64 ll;
+ struct {
+ u32 low, high;
+ } l;
+ } rm, rn, rh, a0, b0;
+ u64 c;
+
+ a0.ll = a;
+ b0.ll = b;
+
+ rm.ll = (u64)a0.l.low * b0.l.high;
+ rn.ll = (u64)a0.l.high * b0.l.low;
+ rh.ll = (u64)a0.l.high * b0.l.high;
+
+ rh.l.low = c = rm.l.high + rn.l.high + rh.l.low;
+ rh.l.high = (c >> 32) + rh.l.high;
+
+ return rh.ll;
+}
+
+static inline void nop_loop(void)
+{
+ int i;
+
+ for (i = 0; i < 1000000; i++)
+ asm volatile("nop");
+}
+
+static inline void check_tsc_msr_rdtsc(void)
+{
+ u64 tsc_freq, r1, r2, t1, t2;
+ s64 delta_ns;
+
+ tsc_freq = rdmsr(HV_X64_MSR_TSC_FREQUENCY);
+ GUEST_ASSERT(tsc_freq > 0);
+
+ /* First, check MSR-based clocksource */
+ r1 = rdtsc();
+ t1 = rdmsr(HV_X64_MSR_TIME_REF_COUNT);
+ nop_loop();
+ r2 = rdtsc();
+ t2 = rdmsr(HV_X64_MSR_TIME_REF_COUNT);
+
+ GUEST_ASSERT(r2 > r1 && t2 > t1);
+
+ /* HV_X64_MSR_TIME_REF_COUNT is in 100ns */
+ delta_ns = ((t2 - t1) * 100) - ((r2 - r1) * 1000000000 / tsc_freq);
+ if (delta_ns < 0)
+ delta_ns = -delta_ns;
+
+ /* 1% tolerance */
+ GUEST_ASSERT(delta_ns * 100 < (t2 - t1) * 100);
+}
+
+static inline void check_tsc_msr_tsc_page(struct ms_hyperv_tsc_page *tsc_page)
+{
+ u64 r1, r2, t1, t2;
+
+ /* Compare TSC page clocksource with HV_X64_MSR_TIME_REF_COUNT */
+ t1 = mul_u64_u64_shr64(rdtsc(), tsc_page->tsc_scale) + tsc_page->tsc_offset;
+ r1 = rdmsr(HV_X64_MSR_TIME_REF_COUNT);
+
+ /* 10 ms tolerance */
+ GUEST_ASSERT(r1 >= t1 && r1 - t1 < 100000);
+ nop_loop();
+
+ t2 = mul_u64_u64_shr64(rdtsc(), tsc_page->tsc_scale) + tsc_page->tsc_offset;
+ r2 = rdmsr(HV_X64_MSR_TIME_REF_COUNT);
+ GUEST_ASSERT(r2 >= t1 && r2 - t2 < 100000);
+}
+
+static void guest_main(struct ms_hyperv_tsc_page *tsc_page, vm_paddr_t tsc_page_gpa)
+{
+ u64 tsc_scale, tsc_offset;
+
+ /* Set Guest OS id to enable Hyper-V emulation */
+ GUEST_SYNC(1);
+ wrmsr(HV_X64_MSR_GUEST_OS_ID, (u64)0x8100 << 48);
+ GUEST_SYNC(2);
+
+ check_tsc_msr_rdtsc();
+
+ GUEST_SYNC(3);
+
+ /* Set up TSC page is disabled state, check that it's clean */
+ wrmsr(HV_X64_MSR_REFERENCE_TSC, tsc_page_gpa);
+ GUEST_ASSERT(tsc_page->tsc_sequence == 0);
+ GUEST_ASSERT(tsc_page->tsc_scale == 0);
+ GUEST_ASSERT(tsc_page->tsc_offset == 0);
+
+ GUEST_SYNC(4);
+
+ /* Set up TSC page is enabled state */
+ wrmsr(HV_X64_MSR_REFERENCE_TSC, tsc_page_gpa | 0x1);
+ GUEST_ASSERT(tsc_page->tsc_sequence != 0);
+
+ GUEST_SYNC(5);
+
+ check_tsc_msr_tsc_page(tsc_page);
+
+ GUEST_SYNC(6);
+
+ tsc_offset = tsc_page->tsc_offset;
+ /* Call KVM_SET_CLOCK from userspace, check that TSC page was updated */
+ GUEST_SYNC(7);
+ GUEST_ASSERT(tsc_page->tsc_offset != tsc_offset);
+
+ nop_loop();
+
+ /*
+ * Enable Re-enlightenment and check that TSC page stays constant across
+ * KVM_SET_CLOCK.
+ */
+ wrmsr(HV_X64_MSR_REENLIGHTENMENT_CONTROL, 0x1 << 16 | 0xff);
+ wrmsr(HV_X64_MSR_TSC_EMULATION_CONTROL, 0x1);
+ tsc_offset = tsc_page->tsc_offset;
+ tsc_scale = tsc_page->tsc_scale;
+ GUEST_SYNC(8);
+ GUEST_ASSERT(tsc_page->tsc_offset == tsc_offset);
+ GUEST_ASSERT(tsc_page->tsc_scale == tsc_scale);
+
+ GUEST_SYNC(9);
+
+ check_tsc_msr_tsc_page(tsc_page);
+
+ /*
+ * Disable re-enlightenment and TSC page, check that KVM doesn't update
+ * it anymore.
+ */
+ wrmsr(HV_X64_MSR_REENLIGHTENMENT_CONTROL, 0);
+ wrmsr(HV_X64_MSR_TSC_EMULATION_CONTROL, 0);
+ wrmsr(HV_X64_MSR_REFERENCE_TSC, 0);
+ memset(tsc_page, 0, sizeof(*tsc_page));
+
+ GUEST_SYNC(10);
+ GUEST_ASSERT(tsc_page->tsc_sequence == 0);
+ GUEST_ASSERT(tsc_page->tsc_offset == 0);
+ GUEST_ASSERT(tsc_page->tsc_scale == 0);
+
+ GUEST_DONE();
+}
+
+#define VCPU_ID 0
+
+static void host_check_tsc_msr_rdtsc(struct kvm_vm *vm)
+{
+ u64 tsc_freq, r1, r2, t1, t2;
+ s64 delta_ns;
+
+ tsc_freq = vcpu_get_msr(vm, VCPU_ID, HV_X64_MSR_TSC_FREQUENCY);
+ TEST_ASSERT(tsc_freq > 0, "TSC frequency must be nonzero");
+
+ /* First, check MSR-based clocksource */
+ r1 = rdtsc();
+ t1 = vcpu_get_msr(vm, VCPU_ID, HV_X64_MSR_TIME_REF_COUNT);
+ nop_loop();
+ r2 = rdtsc();
+ t2 = vcpu_get_msr(vm, VCPU_ID, HV_X64_MSR_TIME_REF_COUNT);
+
+ TEST_ASSERT(t2 > t1, "Time reference MSR is not monotonic (%ld <= %ld)", t1, t2);
+
+ /* HV_X64_MSR_TIME_REF_COUNT is in 100ns */
+ delta_ns = ((t2 - t1) * 100) - ((r2 - r1) * 1000000000 / tsc_freq);
+ if (delta_ns < 0)
+ delta_ns = -delta_ns;
+
+ /* 1% tolerance */
+ TEST_ASSERT(delta_ns * 100 < (t2 - t1) * 100,
+ "Elapsed time does not match (MSR=%ld, TSC=%ld)",
+ (t2 - t1) * 100, (r2 - r1) * 1000000000 / tsc_freq);
+}
+
+int main(void)
+{
+ struct kvm_vm *vm;
+ struct kvm_run *run;
+ struct ucall uc;
+ vm_vaddr_t tsc_page_gva;
+ int stage;
+
+ vm = vm_create_default(VCPU_ID, 0, guest_main);
+ run = vcpu_state(vm, VCPU_ID);
+
+ vcpu_set_hv_cpuid(vm, VCPU_ID);
+
+ tsc_page_gva = vm_vaddr_alloc(vm, getpagesize(), 0x10000, 0, 0);
+ memset(addr_gpa2hva(vm, tsc_page_gva), 0x0, getpagesize());
+ TEST_ASSERT((addr_gva2gpa(vm, tsc_page_gva) & (getpagesize() - 1)) == 0,
+ "TSC page has to be page aligned\n");
+ vcpu_args_set(vm, VCPU_ID, 2, tsc_page_gva, addr_gva2gpa(vm, tsc_page_gva));
+
+ host_check_tsc_msr_rdtsc(vm);
+
+ for (stage = 1;; stage++) {
+ _vcpu_run(vm, VCPU_ID);
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+ "Stage %d: unexpected exit reason: %u (%s),\n",
+ stage, run->exit_reason,
+ exit_reason_str(run->exit_reason));
+
+ switch (get_ucall(vm, VCPU_ID, &uc)) {
+ case UCALL_ABORT:
+ TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0],
+ __FILE__, uc.args[1]);
+ /* NOT REACHED */
+ case UCALL_SYNC:
+ break;
+ case UCALL_DONE:
+ /* Keep in sync with guest_main() */
+ TEST_ASSERT(stage == 11, "Testing ended prematurely, stage %d\n",
+ stage);
+ goto out;
+ default:
+ TEST_FAIL("Unknown ucall %lu", uc.cmd);
+ }
+
+ TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
+ uc.args[1] == stage,
+ "Stage %d: Unexpected register values vmexit, got %lx",
+ stage, (ulong)uc.args[1]);
+
+ /* Reset kvmclock triggering TSC page update */
+ if (stage == 7 || stage == 8 || stage == 10) {
+ struct kvm_clock_data clock = {0};
+
+ vm_ioctl(vm, KVM_SET_CLOCK, &clock);
+ }
+ }
+
+out:
+ kvm_vm_free(vm);
+}
diff --git a/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c b/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c
new file mode 100644
index 000000000000..12c558fc8074
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Test that KVM_SET_BOOT_CPU_ID works as intended
+ *
+ * Copyright (C) 2020, Red Hat, Inc.
+ */
+#define _GNU_SOURCE /* for program_invocation_name */
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+
+#define N_VCPU 2
+#define VCPU_ID0 0
+#define VCPU_ID1 1
+
+static uint32_t get_bsp_flag(void)
+{
+ return rdmsr(MSR_IA32_APICBASE) & MSR_IA32_APICBASE_BSP;
+}
+
+static void guest_bsp_vcpu(void *arg)
+{
+ GUEST_SYNC(1);
+
+ GUEST_ASSERT(get_bsp_flag() != 0);
+
+ GUEST_DONE();
+}
+
+static void guest_not_bsp_vcpu(void *arg)
+{
+ GUEST_SYNC(1);
+
+ GUEST_ASSERT(get_bsp_flag() == 0);
+
+ GUEST_DONE();
+}
+
+static void test_set_boot_busy(struct kvm_vm *vm)
+{
+ int res;
+
+ res = _vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *) VCPU_ID0);
+ TEST_ASSERT(res == -1 && errno == EBUSY,
+ "KVM_SET_BOOT_CPU_ID set while running vm");
+}
+
+static void run_vcpu(struct kvm_vm *vm, uint32_t vcpuid)
+{
+ struct ucall uc;
+ int stage;
+
+ for (stage = 0; stage < 2; stage++) {
+
+ vcpu_run(vm, vcpuid);
+
+ switch (get_ucall(vm, vcpuid, &uc)) {
+ case UCALL_SYNC:
+ TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
+ uc.args[1] == stage + 1,
+ "Stage %d: Unexpected register values vmexit, got %lx",
+ stage + 1, (ulong)uc.args[1]);
+ test_set_boot_busy(vm);
+ break;
+ case UCALL_DONE:
+ TEST_ASSERT(stage == 1,
+ "Expected GUEST_DONE in stage 2, got stage %d",
+ stage);
+ break;
+ case UCALL_ABORT:
+ TEST_ASSERT(false, "%s at %s:%ld\n\tvalues: %#lx, %#lx",
+ (const char *)uc.args[0], __FILE__,
+ uc.args[1], uc.args[2], uc.args[3]);
+ default:
+ TEST_ASSERT(false, "Unexpected exit: %s",
+ exit_reason_str(vcpu_state(vm, vcpuid)->exit_reason));
+ }
+ }
+}
+
+static struct kvm_vm *create_vm(void)
+{
+ struct kvm_vm *vm;
+ uint64_t vcpu_pages = (DEFAULT_STACK_PGS) * 2;
+ uint64_t extra_pg_pages = vcpu_pages / PTES_PER_MIN_PAGE * N_VCPU;
+ uint64_t pages = DEFAULT_GUEST_PHY_PAGES + vcpu_pages + extra_pg_pages;
+
+ pages = vm_adjust_num_guest_pages(VM_MODE_DEFAULT, pages);
+ vm = vm_create(VM_MODE_DEFAULT, pages, O_RDWR);
+
+ kvm_vm_elf_load(vm, program_invocation_name, 0, 0);
+ vm_create_irqchip(vm);
+
+ return vm;
+}
+
+static void add_x86_vcpu(struct kvm_vm *vm, uint32_t vcpuid, bool bsp_code)
+{
+ if (bsp_code)
+ vm_vcpu_add_default(vm, vcpuid, guest_bsp_vcpu);
+ else
+ vm_vcpu_add_default(vm, vcpuid, guest_not_bsp_vcpu);
+
+ vcpu_set_cpuid(vm, vcpuid, kvm_get_supported_cpuid());
+}
+
+static void run_vm_bsp(uint32_t bsp_vcpu)
+{
+ struct kvm_vm *vm;
+ bool is_bsp_vcpu1 = bsp_vcpu == VCPU_ID1;
+
+ vm = create_vm();
+
+ if (is_bsp_vcpu1)
+ vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *) VCPU_ID1);
+
+ add_x86_vcpu(vm, VCPU_ID0, !is_bsp_vcpu1);
+ add_x86_vcpu(vm, VCPU_ID1, is_bsp_vcpu1);
+
+ run_vcpu(vm, VCPU_ID0);
+ run_vcpu(vm, VCPU_ID1);
+
+ kvm_vm_free(vm);
+}
+
+static void check_set_bsp_busy(void)
+{
+ struct kvm_vm *vm;
+ int res;
+
+ vm = create_vm();
+
+ add_x86_vcpu(vm, VCPU_ID0, true);
+ add_x86_vcpu(vm, VCPU_ID1, false);
+
+ res = _vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *) VCPU_ID1);
+ TEST_ASSERT(res == -1 && errno == EBUSY, "KVM_SET_BOOT_CPU_ID set after adding vcpu");
+
+ run_vcpu(vm, VCPU_ID0);
+ run_vcpu(vm, VCPU_ID1);
+
+ res = _vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *) VCPU_ID1);
+ TEST_ASSERT(res == -1 && errno == EBUSY, "KVM_SET_BOOT_CPU_ID set to a terminated vcpu");
+
+ kvm_vm_free(vm);
+}
+
+int main(int argc, char *argv[])
+{
+ if (!kvm_check_cap(KVM_CAP_SET_BOOT_CPU_ID)) {
+ print_skip("set_boot_cpu_id not available");
+ return 0;
+ }
+
+ run_vm_bsp(VCPU_ID0);
+ run_vm_bsp(VCPU_ID1);
+ run_vm_bsp(VCPU_ID0);
+
+ check_set_bsp_busy();
+}