diff options
| author | Christoffer Dall <cdall@linaro.org> | 2017-03-21 22:05:22 +0100 |
|---|---|---|
| committer | Christoffer Dall <cdall@linaro.org> | 2017-04-04 14:33:59 +0200 |
| commit | 6d56111c92d247bb64301029fe88365aa4caf16e (patch) | |
| tree | 0ceec9bfeae39452c020baa35b99f91d9e4bae76 /virt/kvm/arm/vgic/vgic-v2.c | |
| parent | 5b0d2cc2805897c14257f6dbb949639c499c3c25 (diff) | |
| download | lwn-6d56111c92d247bb64301029fe88365aa4caf16e.tar.gz lwn-6d56111c92d247bb64301029fe88365aa4caf16e.zip | |
KVM: arm/arm64: vgic: Fix GICC_PMR uaccess on GICv3 and clarify ABI
As an oversight, for GICv2, we accidentally export the GICC_PMR register
in the format of the GICH_VMCR.VMPriMask field in the lower 5 bits of a
word, meaning that userspace must always use the lower 5 bits to
communicate with the KVM device and must shift the value left by 3
places to obtain the actual priority mask level.
Since GICv3 supports the full 8 bits of priority masking in the ICH_VMCR,
we have to fix the value we export when emulating a GICv2 on top of a
hardware GICv3 and exporting the emulated GICv2 state to userspace.
Take the chance to clarify this aspect of the ABI.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Diffstat (limited to 'virt/kvm/arm/vgic/vgic-v2.c')
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-v2.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c index 94cf4b9b6471..b637d9c7afe3 100644 --- a/virt/kvm/arm/vgic/vgic-v2.c +++ b/virt/kvm/arm/vgic/vgic-v2.c @@ -206,8 +206,8 @@ void vgic_v2_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp) GICH_VMCR_ALIAS_BINPOINT_MASK; vmcr |= (vmcrp->bpr << GICH_VMCR_BINPOINT_SHIFT) & GICH_VMCR_BINPOINT_MASK; - vmcr |= (vmcrp->pmr << GICH_VMCR_PRIMASK_SHIFT) & - GICH_VMCR_PRIMASK_MASK; + vmcr |= ((vmcrp->pmr >> GICV_PMR_PRIORITY_SHIFT) << + GICH_VMCR_PRIMASK_SHIFT) & GICH_VMCR_PRIMASK_MASK; vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = vmcr; } @@ -222,8 +222,8 @@ void vgic_v2_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp) GICH_VMCR_ALIAS_BINPOINT_SHIFT; vmcrp->bpr = (vmcr & GICH_VMCR_BINPOINT_MASK) >> GICH_VMCR_BINPOINT_SHIFT; - vmcrp->pmr = (vmcr & GICH_VMCR_PRIMASK_MASK) >> - GICH_VMCR_PRIMASK_SHIFT; + vmcrp->pmr = ((vmcr & GICH_VMCR_PRIMASK_MASK) >> + GICH_VMCR_PRIMASK_SHIFT) << GICV_PMR_PRIORITY_SHIFT; } void vgic_v2_enable(struct kvm_vcpu *vcpu) |