[PATCH 1/1] KVM: inject data abort if instruction cannot be decoded

From: Heinrich Schuchardt
Date: Wed Sep 04 2019 - 14:20:26 EST


If an application tries to access memory that is not mapped, an error
ENOSYS, "load/store instruction decoding not implemented" may occur.
QEMU will hang with a register dump.

Instead create a data abort that can be handled gracefully by the
application running in the virtual environment.

Now the virtual machine can react to the event in the most appropriate
way - by recovering, by writing an informative log, or by rebooting.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@xxxxxx>
---
virt/kvm/arm/mmio.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/arm/mmio.c b/virt/kvm/arm/mmio.c
index a8a6a0c883f1..0cbed7d6a0f4 100644
--- a/virt/kvm/arm/mmio.c
+++ b/virt/kvm/arm/mmio.c
@@ -161,8 +161,8 @@ int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run,
if (ret)
return ret;
} else {
- kvm_err("load/store instruction decoding not implemented\n");
- return -ENOSYS;
+ kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu));
+ return 1;
}

rt = vcpu->arch.mmio_decode.rt;
--
2.23.0.rc1