diff options
| author | Laurent Vivier <lvivier@redhat.com> | 2016-04-08 18:05:00 +0200 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2016-05-11 13:19:10 +0200 |
| commit | 11dd6ac0254ed9a2b6994e22c903192edd0fa8fc (patch) | |
| tree | b2c1a13f033dc9b1dc54c510633c7333e7df8cfc /arch/powerpc/kvm/book3s_pr.c | |
| parent | Merge tag 'kvms390-20160420' of git://git.kernel.org/pub/scm/linux/kernel/git... (diff) | |
| download | linux-11dd6ac0254ed9a2b6994e22c903192edd0fa8fc.tar.xz linux-11dd6ac0254ed9a2b6994e22c903192edd0fa8fc.zip | |
KVM: PPC: Book3S PR: Manage single-step mode
Until now, when we connect gdb to the QEMU gdb-server, the
single-step mode is not managed.
This patch adds this, only for kvm-pr:
If KVM_GUESTDBG_SINGLESTEP is set, we enable single-step trace bit in the
MSR (MSR_SE) just before the __kvmppc_vcpu_run(), and disable it just after.
In kvmppc_handle_exit_pr, instead of routing the interrupt to
the guest, we return to host, with KVM_EXIT_DEBUG reason.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/kvm/book3s_pr.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_pr.c | 32 |
1 files changed, 31 insertions, 1 deletions
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 95bceca8f40e..8129b0db131e 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -882,6 +882,24 @@ void kvmppc_set_fscr(struct kvm_vcpu *vcpu, u64 fscr) } #endif +static void kvmppc_setup_debug(struct kvm_vcpu *vcpu) +{ + if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) { + u64 msr = kvmppc_get_msr(vcpu); + + kvmppc_set_msr(vcpu, msr | MSR_SE); + } +} + +static void kvmppc_clear_debug(struct kvm_vcpu *vcpu) +{ + if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) { + u64 msr = kvmppc_get_msr(vcpu); + + kvmppc_set_msr(vcpu, msr & ~MSR_SE); + } +} + int kvmppc_handle_exit_pr(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned int exit_nr) { @@ -1207,10 +1225,18 @@ program_interrupt: break; #endif case BOOK3S_INTERRUPT_MACHINE_CHECK: - case BOOK3S_INTERRUPT_TRACE: kvmppc_book3s_queue_irqprio(vcpu, exit_nr); r = RESUME_GUEST; break; + case BOOK3S_INTERRUPT_TRACE: + if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) { + run->exit_reason = KVM_EXIT_DEBUG; + r = RESUME_HOST; + } else { + kvmppc_book3s_queue_irqprio(vcpu, exit_nr); + r = RESUME_GUEST; + } + break; default: { ulong shadow_srr1 = vcpu->arch.shadow_srr1; @@ -1479,6 +1505,8 @@ static int kvmppc_vcpu_run_pr(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) goto out; } + kvmppc_setup_debug(vcpu); + /* * Interrupts could be timers for the guest which we have to inject * again, so let's postpone them until we're in the guest and if we @@ -1501,6 +1529,8 @@ static int kvmppc_vcpu_run_pr(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) ret = __kvmppc_vcpu_run(kvm_run, vcpu); + kvmppc_clear_debug(vcpu); + /* No need for kvm_guest_exit. It's done in handle_exit. We also get here with interrupts enabled. */ |