diff options
author | David S. Miller <davem@davemloft.net> | 2017-03-15 11:59:10 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2017-03-15 11:59:10 -0700 |
commit | 101c431492d297dd0d111b461d8d324895676bee (patch) | |
tree | 06d8a02a4fd91acdd6c31340452e85feaac4ecb7 /virt/kvm/arm/vgic/vgic-mmio.c | |
parent | 9c79ddaa0f962d1f26537a670b0652ff509a6fe0 (diff) | |
parent | 95422dec6bd4a7c57444743f7b1bb375335a6298 (diff) | |
download | linux-101c431492d297dd0d111b461d8d324895676bee.tar.gz linux-101c431492d297dd0d111b461d8d324895676bee.tar.xz |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
drivers/net/ethernet/broadcom/genet/bcmgenet.c
net/core/sock.c
Conflicts were overlapping changes in bcmgenet and the
lockdep handling of sockets.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'virt/kvm/arm/vgic/vgic-mmio.c')
-rw-r--r-- | virt/kvm/arm/vgic/vgic-mmio.c | 32 |
1 files changed, 24 insertions, 8 deletions
diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c index 3654b4c835ef..2a5db1352722 100644 --- a/virt/kvm/arm/vgic/vgic-mmio.c +++ b/virt/kvm/arm/vgic/vgic-mmio.c @@ -180,21 +180,37 @@ unsigned long vgic_mmio_read_active(struct kvm_vcpu *vcpu, static void vgic_mmio_change_active(struct kvm_vcpu *vcpu, struct vgic_irq *irq, bool new_active_state) { + struct kvm_vcpu *requester_vcpu; spin_lock(&irq->irq_lock); + + /* + * The vcpu parameter here can mean multiple things depending on how + * this function is called; when handling a trap from the kernel it + * depends on the GIC version, and these functions are also called as + * part of save/restore from userspace. + * + * Therefore, we have to figure out the requester in a reliable way. + * + * When accessing VGIC state from user space, the requester_vcpu is + * NULL, which is fine, because we guarantee that no VCPUs are running + * when accessing VGIC state from user space so irq->vcpu->cpu is + * always -1. + */ + requester_vcpu = kvm_arm_get_running_vcpu(); + /* * If this virtual IRQ was written into a list register, we * have to make sure the CPU that runs the VCPU thread has - * synced back LR state to the struct vgic_irq. We can only - * know this for sure, when either this irq is not assigned to - * anyone's AP list anymore, or the VCPU thread is not - * running on any CPUs. + * synced back the LR state to the struct vgic_irq. * - * In the opposite case, we know the VCPU thread may be on its - * way back from the guest and still has to sync back this - * IRQ, so we release and re-acquire the spin_lock to let the - * other thread sync back the IRQ. + * As long as the conditions below are true, we know the VCPU thread + * may be on its way back from the guest (we kicked the VCPU thread in + * vgic_change_active_prepare) and still has to sync back this IRQ, + * so we release and re-acquire the spin_lock to let the other thread + * sync back the IRQ. */ while (irq->vcpu && /* IRQ may have state in an LR somewhere */ + irq->vcpu != requester_vcpu && /* Current thread is not the VCPU thread */ irq->vcpu->cpu != -1) /* VCPU thread is running */ cond_resched_lock(&irq->irq_lock); |