| Message ID | 20220121222626.972495-5-farosas@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | KVM: PPC: MMIO fixes | expand |
Excerpts from Fabiano Rosas's message of January 22, 2022 8:26 am: > If MMIO emulation fails we don't want to crash the whole guest by > returning to userspace. > > The original commit bbf45ba57eae ("KVM: ppc: PowerPC 440 KVM > implementation") added a todo: > > /* XXX Deliver Program interrupt to guest. */ > > and later the commit d69614a295ae ("KVM: PPC: Separate loadstore > emulation from priv emulation") added the Program interrupt injection > but in another file, so I'm assuming it was missed that this block > needed to be altered. > > Also change the message to a ratelimited one since we're letting the > guest run and it could flood the host logs. > > Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> One small thing... > --- > arch/powerpc/kvm/powerpc.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c > index 27fb2b70f631..214602c58f13 100644 > --- a/arch/powerpc/kvm/powerpc.c > +++ b/arch/powerpc/kvm/powerpc.c > @@ -307,9 +307,9 @@ int kvmppc_emulate_mmio(struct kvm_vcpu *vcpu) > u32 last_inst; > > kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst); > - /* XXX Deliver Program interrupt to guest. */ > - pr_emerg("%s: emulation failed (%08x)\n", __func__, last_inst); > - r = RESUME_HOST; > + pr_info_ratelimited("KVM: guest access to device memory using unsupported instruction (PID: %d opcode: %#08x)\n", > + current->pid, last_inst); Minor thing but KVM now has some particular printing helpers so I wonder if we should start moving to them in general with our messages. vcpu_debug_ratelimited() maybe? Thanks, Nick
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 27fb2b70f631..214602c58f13 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -307,9 +307,9 @@ int kvmppc_emulate_mmio(struct kvm_vcpu *vcpu) u32 last_inst; kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst); - /* XXX Deliver Program interrupt to guest. */ - pr_emerg("%s: emulation failed (%08x)\n", __func__, last_inst); - r = RESUME_HOST; + pr_info_ratelimited("KVM: guest access to device memory using unsupported instruction (PID: %d opcode: %#08x)\n", + current->pid, last_inst); + r = RESUME_GUEST; break; } default:
If MMIO emulation fails we don't want to crash the whole guest by returning to userspace. The original commit bbf45ba57eae ("KVM: ppc: PowerPC 440 KVM implementation") added a todo: /* XXX Deliver Program interrupt to guest. */ and later the commit d69614a295ae ("KVM: PPC: Separate loadstore emulation from priv emulation") added the Program interrupt injection but in another file, so I'm assuming it was missed that this block needed to be altered. Also change the message to a ratelimited one since we're letting the guest run and it could flood the host logs. Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> --- arch/powerpc/kvm/powerpc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)