Merge git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM bug fixes from Marcelo Tosatti:
 - Fix DS/ES segment register corruption on x86_32.
 - Fix kvmclock wallclock migration offset.
 - Fix PIT interrupt ACK vs system reset logic bug.

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: Fix ds/es corruption on i386 with preemption
  KVM: x86: apply kvmclock offset to guest wall clock time
  KVM: PIC: call ack notifiers for irqs that are dropped form irr

3 files changed, 34 insertions, 7 deletions

diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 1df8fb9e1d5d..e498b18f010c 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -316,6 +316,11 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val)
 	addr &= 1;
 	if (addr == 0) {
 		if (val & 0x10) {
+			u8 edge_irr = s->irr & ~s->elcr;
+			int i;
+			bool found;
+			struct kvm_vcpu *vcpu;
+
 			s->init4 = val & 1;
 			s->last_irr = 0;
 			s->irr &= s->elcr;
@@ -333,6 +338,18 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val)
 			if (val & 0x08)
 				pr_pic_unimpl(
 					"level sensitive irq not supported");
+
+			kvm_for_each_vcpu(i, vcpu, s->pics_state->kvm)
+				if (kvm_apic_accept_pic_intr(vcpu)) {
+					found = true;
+					break;
+				}
+
+
+			if (found)
+				for (irq = 0; irq < PIC_NUM_PINS/2; irq++)
+					if (edge_irr & (1 << irq))
+						pic_clear_isr(s, irq);
 		} else if (val & 0x08) {
 			if (val & 0x04)
 				s->poll = 1;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index c39b60707e02..c00f03de1b79 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1488,13 +1488,6 @@ static void __vmx_load_host_state(struct vcpu_vmx *vmx)
 		loadsegment(ds, vmx->host_state.ds_sel);
 		loadsegment(es, vmx->host_state.es_sel);
 	}
-#else
-	/*
-	 * The sysexit path does not restore ds/es, so we must set them to
-	 * a reasonable value ourselves.
-	 */
-	loadsegment(ds, __USER_DS);
-	loadsegment(es, __USER_DS);
 #endif
 	reload_tss();
 #ifdef CONFIG_X86_64
@@ -6370,6 +6363,19 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
 #endif
 	      );
 
+#ifndef CONFIG_X86_64
+	/*
+	 * The sysexit path does not restore ds/es, so we must set them to
+	 * a reasonable value ourselves.
+	 *
+	 * We can't defer this to vmx_load_host_state() since that function
+	 * may be executed in interrupt context, which saves and restore segments
+	 * around it, nullifying its effect.
+	 */
+	loadsegment(ds, __USER_DS);
+	loadsegment(es, __USER_DS);
+#endif
+
 	vcpu->arch.regs_avail = ~((1 << VCPU_REGS_RIP) | (1 << VCPU_REGS_RSP)
 				  | (1 << VCPU_EXREG_RFLAGS)
 				  | (1 << VCPU_EXREG_CPL)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 59b59508ff07..42bce48f6928 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -925,6 +925,10 @@ static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock)
 	 */
 	getboottime(&boot);
 
+	if (kvm->arch.kvmclock_offset) {
+		struct timespec ts = ns_to_timespec(kvm->arch.kvmclock_offset);
+		boot = timespec_sub(boot, ts);
+	}
 	wc.sec = boot.tv_sec;
 	wc.nsec = boot.tv_nsec;
 	wc.version = version;