On Fri, Jun 14, 2019 at 07:57:45PM +0100, Mark Cave-Ayland wrote:
> QEMU's kvm_handle_debug() function identifies software breakpoints by checking
> for a value of 0 in kvm_debug_exit_arch's status field. Since this field isn't
> explicitly set to 0 when the software breakpoint instruction is detected, any
> previous non-zero value present causes a hang in QEMU as it tries to process
> the breakpoint instruction incorrectly as a hardware breakpoint.
>
> Ensure that the kvm_debug_exit_arch status field is set to 0 when the software
> breakpoint instruction is detected (similar to the existing logic in booke.c
> and e500_emulate.c) to restore software breakpoint functionality under Book3S
> PR.
>
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@xxxxxxxxxxxx>
> ---
> arch/powerpc/kvm/emulate.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c
> index bb4d09c1ad56..6fca38ca791f 100644
> --- a/arch/powerpc/kvm/emulate.c
> +++ b/arch/powerpc/kvm/emulate.c
> @@ -271,6 +271,7 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu)
> */
> if (inst == KVMPPC_INST_SW_BREAKPOINT) {
> run->exit_reason = KVM_EXIT_DEBUG;
> + run->debug.arch.status = 0;
> run->debug.arch.address = kvmppc_get_pc(vcpu);
> emulated = EMULATE_EXIT_USER;
> advance = 0;
Thanks, applied to my kvm-ppc-next branch.
Paul.
