summaryrefslogtreecommitdiffstats
path: root/arch/x86/kvm/x86.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c82
1 files changed, 61 insertions, 21 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e8ba99c3418..d21bce50531 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -618,7 +618,7 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
if (!guest_cpuid_has_smep(vcpu) && (cr4 & X86_CR4_SMEP))
return 1;
- if (!guest_cpuid_has_fsgsbase(vcpu) && (cr4 & X86_CR4_RDWRGSFS))
+ if (!guest_cpuid_has_fsgsbase(vcpu) && (cr4 & X86_CR4_FSGSBASE))
return 1;
if (is_long_mode(vcpu)) {
@@ -1193,20 +1193,37 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr)
elapsed = ns - kvm->arch.last_tsc_nsec;
if (vcpu->arch.virtual_tsc_khz) {
+ int faulted = 0;
+
/* n.b - signed multiplication and division required */
usdiff = data - kvm->arch.last_tsc_write;
#ifdef CONFIG_X86_64
usdiff = (usdiff * 1000) / vcpu->arch.virtual_tsc_khz;
#else
/* do_div() only does unsigned */
- asm("idivl %2; xor %%edx, %%edx"
- : "=A"(usdiff)
- : "A"(usdiff * 1000), "rm"(vcpu->arch.virtual_tsc_khz));
+ asm("1: idivl %[divisor]\n"
+ "2: xor %%edx, %%edx\n"
+ " movl $0, %[faulted]\n"
+ "3:\n"
+ ".section .fixup,\"ax\"\n"
+ "4: movl $1, %[faulted]\n"
+ " jmp 3b\n"
+ ".previous\n"
+
+ _ASM_EXTABLE(1b, 4b)
+
+ : "=A"(usdiff), [faulted] "=r" (faulted)
+ : "A"(usdiff * 1000), [divisor] "rm"(vcpu->arch.virtual_tsc_khz));
+
#endif
do_div(elapsed, 1000);
usdiff -= elapsed;
if (usdiff < 0)
usdiff = -usdiff;
+
+ /* idivl overflow => difference is larger than USEC_PER_SEC */
+ if (faulted)
+ usdiff = USEC_PER_SEC;
} else
usdiff = USEC_PER_SEC; /* disable TSC match window below */
@@ -1587,6 +1604,30 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
return 0;
}
+/*
+ * kvmclock updates which are isolated to a given vcpu, such as
+ * vcpu->cpu migration, should not allow system_timestamp from
+ * the rest of the vcpus to remain static. Otherwise ntp frequency
+ * correction applies to one vcpu's system_timestamp but not
+ * the others.
+ *
+ * So in those cases, request a kvmclock update for all vcpus.
+ * The worst case for a remote vcpu to update its kvmclock
+ * is then bounded by maximum nohz sleep latency.
+ */
+
+static void kvm_gen_kvmclock_update(struct kvm_vcpu *v)
+{
+ int i;
+ struct kvm *kvm = v->kvm;
+ struct kvm_vcpu *vcpu;
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ set_bit(KVM_REQ_CLOCK_UPDATE, &vcpu->requests);
+ kvm_vcpu_kick(vcpu);
+ }
+}
+
static bool msr_mtrr_valid(unsigned msr)
{
switch (msr) {
@@ -1984,7 +2025,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
kvmclock_reset(vcpu);
vcpu->arch.time = data;
- kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
+ kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu);
/* we verify if the enable bit is set... */
if (!(data & 1))
@@ -2701,7 +2742,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
* kvmclock on vcpu->cpu migration
*/
if (!vcpu->kvm->arch.use_master_clock || vcpu->cpu == -1)
- kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
+ kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu);
if (vcpu->cpu != cpu)
kvm_migrate_timers(vcpu);
vcpu->cpu = cpu;
@@ -5238,7 +5279,13 @@ static void kvm_set_mmio_spte_mask(void)
* Set the reserved bits and the present bit of an paging-structure
* entry to generate page fault with PFER.RSV = 1.
*/
- mask = ((1ull << (62 - maxphyaddr + 1)) - 1) << maxphyaddr;
+ /* Mask the reserved physical address bits. */
+ mask = ((1ull << (51 - maxphyaddr + 1)) - 1) << maxphyaddr;
+
+ /* Bit 62 is always reserved for 32bit host. */
+ mask |= 0x3ull << 62;
+
+ /* Set the present bit. */
mask |= 1ull;
#ifdef CONFIG_X86_64
@@ -5498,13 +5545,6 @@ static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt)
char instruction[3];
unsigned long rip = kvm_rip_read(vcpu);
- /*
- * Blow out the MMU to ensure that no other VCPU has an active mapping
- * to ensure that the updated hypercall appears atomically across all
- * VCPUs.
- */
- kvm_mmu_zap_all(vcpu->kvm);
-
kvm_x86_ops->patch_hypercall(vcpu, instruction);
return emulator_write_emulated(ctxt, rip, instruction, 3, NULL);
@@ -5702,6 +5742,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
__kvm_migrate_timers(vcpu);
if (kvm_check_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu))
kvm_gen_update_masterclock(vcpu->kvm);
+ if (kvm_check_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu))
+ kvm_gen_kvmclock_update(vcpu);
if (kvm_check_request(KVM_REQ_CLOCK_UPDATE, vcpu)) {
r = kvm_guest_time_update(vcpu);
if (unlikely(r))
@@ -6812,6 +6854,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
return -EINVAL;
INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
+ INIT_LIST_HEAD(&kvm->arch.zapped_obsolete_pages);
INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
/* Reserve bit 0 of irq_sources_bitmap for userspace irq source */
@@ -7040,22 +7083,18 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
* If memory slot is created, or moved, we need to clear all
* mmio sptes.
*/
- if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
- kvm_mmu_zap_mmio_sptes(kvm);
- kvm_reload_remote_mmus(kvm);
- }
+ kvm_mmu_invalidate_mmio_sptes(kvm);
}
void kvm_arch_flush_shadow_all(struct kvm *kvm)
{
- kvm_mmu_zap_all(kvm);
- kvm_reload_remote_mmus(kvm);
+ kvm_mmu_invalidate_zap_all_pages(kvm);
}
void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
struct kvm_memory_slot *slot)
{
- kvm_arch_flush_shadow_all(kvm);
+ kvm_mmu_invalidate_zap_all_pages(kvm);
}
int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
@@ -7263,3 +7302,4 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intr_vmexit);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_invlpga);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_skinit);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intercepts);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_write_tsc_offset);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-28 18:20:21 +0000