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Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c139
1 files changed, 118 insertions, 21 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d21bce505315..668f19aee6ca 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -682,17 +682,6 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
*/
}
- /*
- * Does the new cr3 value map to physical memory? (Note, we
- * catch an invalid cr3 even in real-mode, because it would
- * cause trouble later on when we turn on paging anyway.)
- *
- * A real CPU would silently accept an invalid cr3 and would
- * attempt to use it - with largely undefined (and often hard
- * to debug) behavior on the guest side.
- */
- if (unlikely(!gfn_to_memslot(vcpu->kvm, cr3 >> PAGE_SHIFT)))
- return 1;
vcpu->arch.cr3 = cr3;
__set_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail);
vcpu->arch.mmu.new_cr3(vcpu);
@@ -850,7 +839,8 @@ static u32 msrs_to_save[] = {
#ifdef CONFIG_X86_64
MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR,
#endif
- MSR_IA32_TSC, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA
+ MSR_IA32_TSC, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA,
+ MSR_IA32_FEATURE_CONTROL
};
static unsigned num_msrs_to_save;
@@ -4955,6 +4945,97 @@ static bool retry_instruction(struct x86_emulate_ctxt *ctxt,
static int complete_emulated_mmio(struct kvm_vcpu *vcpu);
static int complete_emulated_pio(struct kvm_vcpu *vcpu);
+static int kvm_vcpu_check_hw_bp(unsigned long addr, u32 type, u32 dr7,
+ unsigned long *db)
+{
+ u32 dr6 = 0;
+ int i;
+ u32 enable, rwlen;
+
+ enable = dr7;
+ rwlen = dr7 >> 16;
+ for (i = 0; i < 4; i++, enable >>= 2, rwlen >>= 4)
+ if ((enable & 3) && (rwlen & 15) == type && db[i] == addr)
+ dr6 |= (1 << i);
+ return dr6;
+}
+
+static void kvm_vcpu_check_singlestep(struct kvm_vcpu *vcpu, int *r)
+{
+ struct kvm_run *kvm_run = vcpu->run;
+
+ /*
+ * Use the "raw" value to see if TF was passed to the processor.
+ * Note that the new value of the flags has not been saved yet.
+ *
+ * This is correct even for TF set by the guest, because "the
+ * processor will not generate this exception after the instruction
+ * that sets the TF flag".
+ */
+ unsigned long rflags = kvm_x86_ops->get_rflags(vcpu);
+
+ if (unlikely(rflags & X86_EFLAGS_TF)) {
+ if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
+ kvm_run->debug.arch.dr6 = DR6_BS | DR6_FIXED_1;
+ kvm_run->debug.arch.pc = vcpu->arch.singlestep_rip;
+ kvm_run->debug.arch.exception = DB_VECTOR;
+ kvm_run->exit_reason = KVM_EXIT_DEBUG;
+ *r = EMULATE_USER_EXIT;
+ } else {
+ vcpu->arch.emulate_ctxt.eflags &= ~X86_EFLAGS_TF;
+ /*
+ * "Certain debug exceptions may clear bit 0-3. The
+ * remaining contents of the DR6 register are never
+ * cleared by the processor".
+ */
+ vcpu->arch.dr6 &= ~15;
+ vcpu->arch.dr6 |= DR6_BS;
+ kvm_queue_exception(vcpu, DB_VECTOR);
+ }
+ }
+}
+
+static bool kvm_vcpu_check_breakpoint(struct kvm_vcpu *vcpu, int *r)
+{
+ struct kvm_run *kvm_run = vcpu->run;
+ unsigned long eip = vcpu->arch.emulate_ctxt.eip;
+ u32 dr6 = 0;
+
+ if (unlikely(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) &&
+ (vcpu->arch.guest_debug_dr7 & DR7_BP_EN_MASK)) {
+ dr6 = kvm_vcpu_check_hw_bp(eip, 0,
+ vcpu->arch.guest_debug_dr7,
+ vcpu->arch.eff_db);
+
+ if (dr6 != 0) {
+ kvm_run->debug.arch.dr6 = dr6 | DR6_FIXED_1;
+ kvm_run->debug.arch.pc = kvm_rip_read(vcpu) +
+ get_segment_base(vcpu, VCPU_SREG_CS);
+
+ kvm_run->debug.arch.exception = DB_VECTOR;
+ kvm_run->exit_reason = KVM_EXIT_DEBUG;
+ *r = EMULATE_USER_EXIT;
+ return true;
+ }
+ }
+
+ if (unlikely(vcpu->arch.dr7 & DR7_BP_EN_MASK)) {
+ dr6 = kvm_vcpu_check_hw_bp(eip, 0,
+ vcpu->arch.dr7,
+ vcpu->arch.db);
+
+ if (dr6 != 0) {
+ vcpu->arch.dr6 &= ~15;
+ vcpu->arch.dr6 |= dr6;
+ kvm_queue_exception(vcpu, DB_VECTOR);
+ *r = EMULATE_DONE;
+ return true;
+ }
+ }
+
+ return false;
+}
+
int x86_emulate_instruction(struct kvm_vcpu *vcpu,
unsigned long cr2,
int emulation_type,
@@ -4975,6 +5056,16 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu,
if (!(emulation_type & EMULTYPE_NO_DECODE)) {
init_emulate_ctxt(vcpu);
+
+ /*
+ * We will reenter on the same instruction since
+ * we do not set complete_userspace_io. This does not
+ * handle watchpoints yet, those would be handled in
+ * the emulate_ops.
+ */
+ if (kvm_vcpu_check_breakpoint(vcpu, &r))
+ return r;
+
ctxt->interruptibility = 0;
ctxt->have_exception = false;
ctxt->perm_ok = false;
@@ -5037,11 +5128,11 @@ restart:
writeback = false;
vcpu->arch.complete_userspace_io = complete_emulated_pio;
}
- r = EMULATE_DO_MMIO;
+ r = EMULATE_USER_EXIT;
} else if (vcpu->mmio_needed) {
if (!vcpu->mmio_is_write)
writeback = false;
- r = EMULATE_DO_MMIO;
+ r = EMULATE_USER_EXIT;
vcpu->arch.complete_userspace_io = complete_emulated_mmio;
} else if (r == EMULATION_RESTART)
goto restart;
@@ -5050,10 +5141,12 @@ restart:
if (writeback) {
toggle_interruptibility(vcpu, ctxt->interruptibility);
- kvm_set_rflags(vcpu, ctxt->eflags);
kvm_make_request(KVM_REQ_EVENT, vcpu);
vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
kvm_rip_write(vcpu, ctxt->eip);
+ if (r == EMULATE_DONE)
+ kvm_vcpu_check_singlestep(vcpu, &r);
+ kvm_set_rflags(vcpu, ctxt->eflags);
} else
vcpu->arch.emulate_regs_need_sync_to_vcpu = true;
@@ -5347,7 +5440,7 @@ static struct notifier_block pvclock_gtod_notifier = {
int kvm_arch_init(void *opaque)
{
int r;
- struct kvm_x86_ops *ops = (struct kvm_x86_ops *)opaque;
+ struct kvm_x86_ops *ops = opaque;
if (kvm_x86_ops) {
printk(KERN_ERR "kvm: already loaded the other module\n");
@@ -7019,6 +7112,15 @@ out_free:
return -ENOMEM;
}
+void kvm_arch_memslots_updated(struct kvm *kvm)
+{
+ /*
+ * memslots->generation has been incremented.
+ * mmio generation may have reached its maximum value.
+ */
+ kvm_mmu_invalidate_mmio_sptes(kvm);
+}
+
int kvm_arch_prepare_memory_region(struct kvm *kvm,
struct kvm_memory_slot *memslot,
struct kvm_userspace_memory_region *mem,
@@ -7079,11 +7181,6 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
*/
if ((change != KVM_MR_DELETE) && (mem->flags & KVM_MEM_LOG_DIRTY_PAGES))
kvm_mmu_slot_remove_write_access(kvm, mem->slot);
- /*
- * If memory slot is created, or moved, we need to clear all
- * mmio sptes.
- */
- kvm_mmu_invalidate_mmio_sptes(kvm);
}
void kvm_arch_flush_shadow_all(struct kvm *kvm)
generated by cgit v1.2.3 (git 2.39.0) at 2024-07-21 07:58:24 +0300