| Message ID | 1405573011-41330-2-git-send-email-wanpeng.li@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Wanpeng Li wrote on 2014-07-17: > WARNING: CPU: 9 PID: 7251 at arch/x86/kvm/vmx.c:8719 > nested_vmx_vmexit+0xa4/0x233 [kvm_intel]() Modules linked in: tun > nfsv3 nfs_acl auth_rpcgss oid_registry nfsv4 dns_resolver nfs fscache > lockd sunrpc pci_stub netconsole kvm_intel kvm bridge stp llc autofs4 > 8021q ipv6 uinput joydev microcode pcspkr igb i2c_algo_bit ehci_pci > ehci_hcd e1000e ixgbe ptp pps_core hwmon mdio i2c_i801 i2c_core > tpm_tis tpm ipmi_si ipmi_msghandler isci libsas scsi_transport_sas > button dm_mirror dm_region_hash dm_log dm_mod > CPU: 9 PID: 7251 Comm: qemu-system-x86 Tainted: G W > 3.16.0-rc1 #2 > Hardware name: Intel Corporation S2600CP/S2600CP, BIOS > RMLSDP.86I.00.29.D696.1311111329 11/11/2013 000000000000220f > ffff880ffd107bf8 ffffffff81493563 000000000000220f > 0000000000000000 ffff880ffd107c38 ffffffff8103f0eb ffff880ffd107c48 > ffffffffa059709a ffff881ffc9e0040 ffff8800b74b8000 00000000ffffffff > Call Trace: [<ffffffff81493563>] dump_stack+0x49/0x5e > [<ffffffff8103f0eb>] > warn_slowpath_common+0x7c/0x96 [<ffffffffa059709a>] ? > nested_vmx_vmexit+0xa4/0x233 [kvm_intel] [<ffffffff8103f11a>] > warn_slowpath_null+0x15/0x17 [<ffffffffa059709a>] > nested_vmx_vmexit+0xa4/0x233 [kvm_intel] [<ffffffffa0594295>] ? > nested_vmx_exit_handled+0x6a/0x39e [kvm_intel] [<ffffffffa0537931>] ? > kvm_apic_has_interrupt+0x80/0xd5 [kvm] [<ffffffffa05972ec>] > vmx_check_nested_events+0xc3/0xd3 [kvm_intel] [<ffffffffa051ebe9>] > inject_pending_event+0xd0/0x16e [kvm] [<ffffffffa051efa0>] > vcpu_enter_guest+0x319/0x704 [kvm] > > After commit 77b0f5d (KVM: nVMX: Ack and write vector info to > intr_info if L1 asks us to), "Acknowledge interrupt on exit" behavior > can be emulated. Current logic will ask for intr vector if it is > nested vmexit and VM_EXIT_ACK_INTR_ON_EXIT is set by L1. However, intr > vector for posted intr can't be got by generic read pending interrupt > vector and intack routine, there is a requirement to sync from pir to > irr. This patch fix it by ask the intr vector after sync pir to irr. > > Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Reviewed-by: Yang Zhang <yang.z.zhang@intel.com> > --- > arch/x86/kvm/lapic.c | 1 + > arch/x86/kvm/vmx.c | 3 +++ > 2 files changed, 4 insertions(+) > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index > 0069118..b7d45dc 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -1637,6 +1637,7 @@ int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu) > apic_clear_irr(vector, apic); > return vector; > } > +EXPORT_SYMBOL_GPL(kvm_get_apic_interrupt); > > void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu, > struct kvm_lapic_state *s) > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index > 4ae5ad8..31f1479 100644 --- a/arch/x86/kvm/vmx.c +++ > b/arch/x86/kvm/vmx.c @@ -8697,6 +8697,9 @@ static void > nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason, > if ((exit_reason == EXIT_REASON_EXTERNAL_INTERRUPT) > && nested_exit_intr_ack_set(vcpu)) { > int irq = kvm_cpu_get_interrupt(vcpu); > + > + if (irq < 0 && kvm_apic_vid_enabled(vcpu->kvm)) > + irq = kvm_get_apic_interrupt(vcpu); > WARN_ON(irq < 0); > vmcs12->vm_exit_intr_info = irq | > INTR_INFO_VALID_MASK | INTR_TYPE_EXT_INTR; Best regards, Yang -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Paolo Bonzini wrote on 2014-07-17: > Il 17/07/2014 06:56, Wanpeng Li ha scritto: >> && nested_exit_intr_ack_set(vcpu)) { >> int irq = kvm_cpu_get_interrupt(vcpu); >> + >> + if (irq < 0 && kvm_apic_vid_enabled(vcpu->kvm)) >> + irq = kvm_get_apic_interrupt(vcpu); > > There's something weird in this patch. If you "inline" > kvm_cpu_get_interrupt, what you get is this: > > int irq; > /* Beginning of kvm_cpu_get_interrupt... */ > if (!irqchip_in_kernel(v->kvm)) > irq = v->arch.interrupt.nr; > else { > irq = kvm_cpu_get_extint(v); /* PIC */ > if (!kvm_apic_vid_enabled(v->kvm) && irq == -1) > irq = kvm_get_apic_interrupt(v); /* APIC */ > } > > /* kvm_cpu_get_interrupt done. */ > if (irq < 0 && kvm_apic_vid_enabled(vcpu->kvm)) > irq = kvm_get_apic_interrupt(vcpu); > > There are just two callers of kvm_cpu_get_interrupt, and the other is > protected by kvm_cpu_has_injectable_intr so it won't be executed if > virtual interrupt delivery is enabled. So you patch is effectively the same as this: > > diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c index > bd0da43..a1ec6a5 100644 --- a/arch/x86/kvm/irq.c +++ > b/arch/x86/kvm/irq.c @@ -108,7 +108,7 @@ int > kvm_cpu_get_interrupt(struct kvm_vcpu *v) > > vector = kvm_cpu_get_extint(v); > - if (kvm_apic_vid_enabled(v->kvm) || vector != -1) > + if (vector != -1) > return vector; /* PIC */ > > return kvm_get_apic_interrupt(v); /* APIC */ > But in kvm_get_apic_interrupt I have just added this comment: > > /* Note that we never get here with APIC virtualization > * enabled. */ > > because kvm_get_apic_interrupt calls apic_set_isr, and apic_set_isr > must never be called with APIC virtualization enabled either. With > APIC virtualization enabled, isr_count is always 1, and > highest_isr_cache is always -1, and apic_set_isr breaks both of these invariants. > You are right. kvm_lapic_find_highest_irr should be the right one. > Paolo Best regards, Yang -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 0069118..b7d45dc 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1637,6 +1637,7 @@ int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu) apic_clear_irr(vector, apic); return vector; } +EXPORT_SYMBOL_GPL(kvm_get_apic_interrupt); void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 4ae5ad8..31f1479 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -8697,6 +8697,9 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason, if ((exit_reason == EXIT_REASON_EXTERNAL_INTERRUPT) && nested_exit_intr_ack_set(vcpu)) { int irq = kvm_cpu_get_interrupt(vcpu); + + if (irq < 0 && kvm_apic_vid_enabled(vcpu->kvm)) + irq = kvm_get_apic_interrupt(vcpu); WARN_ON(irq < 0); vmcs12->vm_exit_intr_info = irq | INTR_INFO_VALID_MASK | INTR_TYPE_EXT_INTR;
WARNING: CPU: 9 PID: 7251 at arch/x86/kvm/vmx.c:8719 nested_vmx_vmexit+0xa4/0x233 [kvm_intel]() Modules linked in: tun nfsv3 nfs_acl auth_rpcgss oid_registry nfsv4 dns_resolver nfs fscache lockd sunrpc pci_stub netconsole kvm_intel kvm bridge stp llc autofs4 8021q ipv6 uinput joydev microcode pcspkr igb i2c_algo_bit ehci_pci ehci_hcd e1000e ixgbe ptp pps_core hwmon mdio i2c_i801 i2c_core tpm_tis tpm ipmi_si ipmi_msghandler isci libsas scsi_transport_sas button dm_mirror dm_region_hash dm_log dm_mod CPU: 9 PID: 7251 Comm: qemu-system-x86 Tainted: G W 3.16.0-rc1 #2 Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013 000000000000220f ffff880ffd107bf8 ffffffff81493563 000000000000220f 0000000000000000 ffff880ffd107c38 ffffffff8103f0eb ffff880ffd107c48 ffffffffa059709a ffff881ffc9e0040 ffff8800b74b8000 00000000ffffffff Call Trace: [<ffffffff81493563>] dump_stack+0x49/0x5e [<ffffffff8103f0eb>] warn_slowpath_common+0x7c/0x96 [<ffffffffa059709a>] ? nested_vmx_vmexit+0xa4/0x233 [kvm_intel] [<ffffffff8103f11a>] warn_slowpath_null+0x15/0x17 [<ffffffffa059709a>] nested_vmx_vmexit+0xa4/0x233 [kvm_intel] [<ffffffffa0594295>] ? nested_vmx_exit_handled+0x6a/0x39e [kvm_intel] [<ffffffffa0537931>] ? kvm_apic_has_interrupt+0x80/0xd5 [kvm] [<ffffffffa05972ec>] vmx_check_nested_events+0xc3/0xd3 [kvm_intel] [<ffffffffa051ebe9>] inject_pending_event+0xd0/0x16e [kvm] [<ffffffffa051efa0>] vcpu_enter_guest+0x319/0x704 [kvm] After commit 77b0f5d (KVM: nVMX: Ack and write vector info to intr_info if L1 asks us to), "Acknowledge interrupt on exit" behavior can be emulated. Current logic will ask for intr vector if it is nested vmexit and VM_EXIT_ACK_INTR_ON_EXIT is set by L1. However, intr vector for posted intr can't be got by generic read pending interrupt vector and intack routine, there is a requirement to sync from pir to irr. This patch fix it by ask the intr vector after sync pir to irr. Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> --- arch/x86/kvm/lapic.c | 1 + arch/x86/kvm/vmx.c | 3 +++ 2 files changed, 4 insertions(+)