From b6ac069532218027f2991cba01d7a72a200688b0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Date: Fri, 5 Jun 2015 20:57:41 +0200 Subject: [PATCH] KVM: x86: fix lapic.timer_mode on restore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit lapic.timer_mode was not properly initialized after migration, which broke few useful things, like login, by making every sleep eternal. Fix this by calling apic_update_lvtt in kvm_apic_post_state_restore. There are other slowpaths that update lvtt, so this patch makes sure something similar doesn't happen again by calling apic_update_lvtt after every modification. Cc: stable@vger.kernel.org Fixes: f30ebc312ca9 ("KVM: x86: optimize some accesses to LVTT and SPIV") Signed-off-by: Radim Krčmář Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/lapic.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 629af0f1c5c4..4c7deb4f78a1 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1090,6 +1090,17 @@ static void update_divide_count(struct kvm_lapic *apic) apic->divide_count); } +static void apic_update_lvtt(struct kvm_lapic *apic) +{ + u32 timer_mode = kvm_apic_get_reg(apic, APIC_LVTT) & + apic->lapic_timer.timer_mode_mask; + + if (apic->lapic_timer.timer_mode != timer_mode) { + apic->lapic_timer.timer_mode = timer_mode; + hrtimer_cancel(&apic->lapic_timer.timer); + } +} + static void apic_timer_expired(struct kvm_lapic *apic) { struct kvm_vcpu *vcpu = apic->vcpu; @@ -1298,6 +1309,7 @@ static int apic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val) apic_set_reg(apic, APIC_LVTT + 0x10 * i, lvt_val | APIC_LVT_MASKED); } + apic_update_lvtt(apic); atomic_set(&apic->lapic_timer.pending, 0); } @@ -1330,20 +1342,13 @@ static int apic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val) break; - case APIC_LVTT: { - u32 timer_mode = val & apic->lapic_timer.timer_mode_mask; - - if (apic->lapic_timer.timer_mode != timer_mode) { - apic->lapic_timer.timer_mode = timer_mode; - hrtimer_cancel(&apic->lapic_timer.timer); - } - + case APIC_LVTT: if (!kvm_apic_sw_enabled(apic)) val |= APIC_LVT_MASKED; val &= (apic_lvt_mask[0] | apic->lapic_timer.timer_mode_mask); apic_set_reg(apic, APIC_LVTT, val); + apic_update_lvtt(apic); break; - } case APIC_TMICT: if (apic_lvtt_tscdeadline(apic)) @@ -1576,7 +1581,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu) for (i = 0; i < APIC_LVT_NUM; i++) apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED); - apic->lapic_timer.timer_mode = 0; + apic_update_lvtt(apic); apic_set_reg(apic, APIC_LVT0, SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT)); @@ -1802,6 +1807,7 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu, apic_update_ppr(apic); hrtimer_cancel(&apic->lapic_timer.timer); + apic_update_lvtt(apic); update_divide_count(apic); start_apic_timer(apic); apic->irr_pending = true;