diff options
| author | Andrew Jones <drjones@redhat.com> | 2017-06-04 14:43:59 +0200 |
|---|---|---|
| committer | Christoffer Dall <cdall@linaro.org> | 2017-06-04 16:53:56 +0200 |
| commit | 325f9c649c8a4e447e4d3babacc7a60b75012d5d (patch) | |
| tree | 193beeeb76fd967f942f97e02c358af571c3144b /virt | |
| parent | KVM: arm/arm64: change exit request to sleep request (diff) | |
| download | linux-325f9c649c8a4e447e4d3babacc7a60b75012d5d.tar.xz linux-325f9c649c8a4e447e4d3babacc7a60b75012d5d.zip | |
KVM: arm/arm64: use vcpu requests for irq injection
Don't use request-less VCPU kicks when injecting IRQs, as a VCPU
kick meant to trigger the interrupt injection could be sent while
the VCPU is outside guest mode, which means no IPI is sent, and
after it has called kvm_vgic_flush_hwstate(), meaning it won't see
the updated GIC state until its next exit some time later for some
other reason. The receiving VCPU only needs to check this request
in VCPU RUN to handle it. By checking it, if it's pending, a
memory barrier will be issued that ensures all state is visible.
See "Ensuring Requests Are Seen" of
Documentation/virtual/kvm/vcpu-requests.rst
Signed-off-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/arm/arm.c | 7 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic/vgic.c | 9 |
2 files changed, 14 insertions, 2 deletions
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c index ddc833987dfb..cac5c2f2ddba 100644 --- a/virt/kvm/arm/arm.c +++ b/virt/kvm/arm/arm.c @@ -580,6 +580,12 @@ static void check_vcpu_requests(struct kvm_vcpu *vcpu) if (kvm_request_pending(vcpu)) { if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) vcpu_req_sleep(vcpu); + + /* + * Clear IRQ_PENDING requests that were made to guarantee + * that a VCPU sees new virtual interrupts. + */ + kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); } } @@ -771,6 +777,7 @@ static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) * trigger a world-switch round on the running physical CPU to set the * virtual IRQ/FIQ fields in the HCR appropriately. */ + kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); kvm_vcpu_kick(vcpu); return 0; diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c index aea080a2c443..c66feaca2a5d 100644 --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -286,8 +286,10 @@ retry: * won't see this one until it exits for some other * reason. */ - if (vcpu) + if (vcpu) { + kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); kvm_vcpu_kick(vcpu); + } return false; } @@ -333,6 +335,7 @@ retry: spin_unlock(&irq->irq_lock); spin_unlock(&vcpu->arch.vgic_cpu.ap_list_lock); + kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); kvm_vcpu_kick(vcpu); return true; @@ -722,8 +725,10 @@ void vgic_kick_vcpus(struct kvm *kvm) * a good kick... */ kvm_for_each_vcpu(c, vcpu, kvm) { - if (kvm_vgic_vcpu_pending_irq(vcpu)) + if (kvm_vgic_vcpu_pending_irq(vcpu)) { + kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); kvm_vcpu_kick(vcpu); + } } } |