KVM: PPC: Book3S PR: Fix software breakpoints

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@ilande.co.uk>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Mark Cave-Ayland 2019-06-14 19:57:45 +01:00 committed by Paul Mackerras
parent 0e84ec96b5
commit 3bda7f0ae0

View File

@ -282,6 +282,7 @@ 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;