| Message ID | 20220921003201.1441511-12-seanjc@google.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | KVM: x86: never write to memory from kvm_vcpu_check_block | expand |
On Wed, Sep 21, 2022 at 2:34 AM Sean Christopherson <seanjc@google.com> wrote: > > From: Paolo Bonzini <pbonzini@redhat.com> > > KVM_REQ_UNHALT is a weird request that simply reports the value of > kvm_arch_vcpu_runnable() on exit from kvm_vcpu_halt(). Only > MIPS and x86 are looking at it, the others just clear it. Check > the state of the vCPU directly so that the request is handled > as a nop on all architectures. > > No functional change intended, except for corner cases where an > event arrive immediately after a signal become pending or after > another similar host-side event. > > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > arch/mips/kvm/emulate.c | 7 +++---- > arch/x86/kvm/x86.c | 9 ++++++++- > 2 files changed, 11 insertions(+), 5 deletions(-) Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c index b494d8d39290..1d7c56defe93 100644 --- a/arch/mips/kvm/emulate.c +++ b/arch/mips/kvm/emulate.c @@ -955,13 +955,12 @@ enum emulation_result kvm_mips_emul_wait(struct kvm_vcpu *vcpu) kvm_vcpu_halt(vcpu); /* - * We we are runnable, then definitely go off to user space to + * We are runnable, then definitely go off to user space to * check if any I/O interrupts are pending. */ - if (kvm_check_request(KVM_REQ_UNHALT, vcpu)) { - kvm_clear_request(KVM_REQ_UNHALT, vcpu); + kvm_clear_request(KVM_REQ_UNHALT, vcpu); + if (kvm_arch_vcpu_runnable(vcpu)) vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN; - } } return EMULATE_DONE; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8aeacbc2bff9..8b1ff7e91ecb 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -10811,7 +10811,14 @@ static inline int vcpu_block(struct kvm_vcpu *vcpu) if (hv_timer) kvm_lapic_switch_to_hv_timer(vcpu); - if (!kvm_check_request(KVM_REQ_UNHALT, vcpu)) + kvm_clear_request(KVM_REQ_UNHALT, vcpu); + + /* + * If the vCPU is not runnable, a signal or another host event + * of some kind is pending; service it without changing the + * vCPU's activity state. + */ + if (!kvm_arch_vcpu_runnable(vcpu)) return 1; }