[PULL 12/19] kvm: arm64: handle single-step of userspace mmio instructions

Christoffer Dall cdall at kernel.org
Mon Dec 4 06:03:41 PST 2017


From: Alex Bennée <alex.bennee at linaro.org>

The system state of KVM when using userspace emulation is not complete
until we return into KVM_RUN. To handle mmio related updates we wait
until they have been committed and then schedule our KVM_EXIT_DEBUG.

The kvm_arm_handle_step_debug() helper tells us if we need to return
and sets up the exit_reason for us.

Signed-off-by: Alex Bennée <alex.bennee at linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall at linaro.org>
---
 virt/kvm/arm/arm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index a6524ff27de4..322c570d211e 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -628,6 +628,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		ret = kvm_handle_mmio_return(vcpu, vcpu->run);
 		if (ret)
 			return ret;
+		if (kvm_arm_handle_step_debug(vcpu, vcpu->run))
+			return 0;
+
 	}
 
 	if (run->immediate_exit)
-- 
2.14.2




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