From: Wanpeng Li <wanpeng.li@hotmail.com>
Date: Thu, 24 Aug 2017 03:35:11 -0700
Subject: KVM: nVMX: Fix trying to cancel vmlauch/vmresume
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Content-Type: text/plain; charset=UTF-8
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Patch-mainline: v4.14-rc1
Git-commit: bfcf83b1444d90f6e680a0dde0916f3b289b5066
References: bsc#1077761
------------[ cut here ]------------
WARNING: CPU: 7 PID: 3861 at /home/kernel/ssd/kvm/arch/x86/kvm//vmx.c:11299 nested_vmx_vmexit+0x176e/0x1980 [kvm_intel]
CPU: 7 PID: 3861 Comm: qemu-system-x86 Tainted: G W OE 4.13.0-rc4+ #11
RIP: 0010:nested_vmx_vmexit+0x176e/0x1980 [kvm_intel]
Call Trace:
? kvm_multiple_exception+0x149/0x170 [kvm]
? handle_emulation_failure+0x79/0x230 [kvm]
? load_vmcs12_host_state+0xa80/0xa80 [kvm_intel]
? check_chain_key+0x137/0x1e0
? reexecute_instruction.part.168+0x130/0x130 [kvm]
nested_vmx_inject_exception_vmexit+0xb7/0x100 [kvm_intel]
? nested_vmx_inject_exception_vmexit+0xb7/0x100 [kvm_intel]
vmx_queue_exception+0x197/0x300 [kvm_intel]
kvm_arch_vcpu_ioctl_run+0x1b0c/0x2c90 [kvm]
? kvm_arch_vcpu_runnable+0x220/0x220 [kvm]
? preempt_count_sub+0x18/0xc0
? restart_apic_timer+0x17d/0x300 [kvm]
? kvm_lapic_restart_hv_timer+0x37/0x50 [kvm]
? kvm_arch_vcpu_load+0x1d8/0x350 [kvm]
kvm_vcpu_ioctl+0x4e4/0x910 [kvm]
? kvm_vcpu_ioctl+0x4e4/0x910 [kvm]
? kvm_dev_ioctl+0xbe0/0xbe0 [kvm]
The flag "nested_run_pending", which can override the decision of which should run
next, L1 or L2. nested_run_pending=1 means that we *must* run L2 next, not L1. This
is necessary in particular when L1 did a VMLAUNCH of L2 and therefore expects L2 to
be run (and perhaps be injected with an event it specified, etc.). Nested_run_pending
is especially intended to avoid switching to L1 in the injection decision-point.
This can be handled just like the other cases in vmx_check_nested_events, instead of
having a special case in vmx_queue_exception.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
arch/x86/kvm/vmx.c | 31 +++++++++++++++++--------------
1 file changed, 17 insertions(+), 14 deletions(-)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2462,15 +2462,14 @@
* KVM wants to inject page-faults which it got to the guest. This function
* checks whether in a nested guest, we need to inject them to L1 or L2.
*/
-static int nested_vmx_check_exception(struct kvm_vcpu *vcpu)
+static int nested_vmx_check_exception(struct kvm_vcpu *vcpu, unsigned long *exit_qual)
{
struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
unsigned int nr = vcpu->arch.exception.nr;
if (nr == PF_VECTOR) {
if (vcpu->arch.exception.nested_apf) {
- nested_vmx_inject_exception_vmexit(vcpu,
- vcpu->arch.apf.nested_apf_token);
+ *exit_qual = vcpu->arch.apf.nested_apf_token;
return 1;
}
/*
@@ -2484,16 +2483,15 @@
*/
if (nested_vmx_is_page_fault_vmexit(vmcs12,
vcpu->arch.exception.error_code)) {
- nested_vmx_inject_exception_vmexit(vcpu, vcpu->arch.cr2);
+ *exit_qual = vcpu->arch.cr2;
return 1;
}
} else {
- unsigned long exit_qual = 0;
- if (nr == DB_VECTOR)
- exit_qual = vcpu->arch.dr6;
-
if (vmcs12->exception_bitmap & (1u << nr)) {
- nested_vmx_inject_exception_vmexit(vcpu, exit_qual);
+ if (nr == DB_VECTOR)
+ *exit_qual = vcpu->arch.dr6;
+ else
+ *exit_qual = 0;
return 1;
}
}
@@ -2506,14 +2504,9 @@
struct vcpu_vmx *vmx = to_vmx(vcpu);
unsigned nr = vcpu->arch.exception.nr;
bool has_error_code = vcpu->arch.exception.has_error_code;
- bool reinject = vcpu->arch.exception.injected;
u32 error_code = vcpu->arch.exception.error_code;
u32 intr_info = nr | INTR_INFO_VALID_MASK;
- if (!reinject && is_guest_mode(vcpu) &&
- nested_vmx_check_exception(vcpu))
- return;
-
if (has_error_code) {
vmcs_write32(VM_ENTRY_EXCEPTION_ERROR_CODE, error_code);
intr_info |= INTR_INFO_DELIVER_CODE_MASK;
@@ -10986,10 +10979,20 @@
static int vmx_check_nested_events(struct kvm_vcpu *vcpu, bool external_intr)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
+ unsigned long exit_qual;
if (kvm_event_needs_reinjection(vcpu))
return -EBUSY;
+ if (vcpu->arch.exception.pending &&
+ nested_vmx_check_exception(vcpu, &exit_qual)) {
+ if (vmx->nested.nested_run_pending)
+ return -EBUSY;
+ nested_vmx_inject_exception_vmexit(vcpu, exit_qual);
+ vcpu->arch.exception.pending = false;
+ return 0;
+ }
+
if (nested_cpu_has_preemption_timer(get_vmcs12(vcpu)) &&
vmx->nested.preemption_timer_expired) {
if (vmx->nested.nested_run_pending)