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KVM: mips, x86: do not rely on KVM_REQ_UNHALT

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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>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220921003201.1441511-12-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2022-09-21 00:32:00 +00:00
parent 26844fee6a
commit 599275c060
2 changed files with 11 additions and 5 deletions
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7
arch/mips/kvm/emulate.c
View File

@ -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;

9
arch/x86/kvm/x86.c
View File

@ -10813,7 +10813,14 @@ 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;
}