| Message ID | 1389338467-26303-1-git-send-email-aik@ozlabs.ru |
|---|---|
| State | New, archived |
| Headers | show |
On 10.01.2014, at 08:21, Alexey Kardashevskiy <aik@ozlabs.ru> wrote: > When write to MMIO happens and there is an ioeventfd for that and > is handled successfully, ioeventfd_write() returns 0 (success) and > kvmppc_handle_store() returns EMULATE_DONE. Then kvmppc_emulate_mmio() > converts EMULATE_DONE to RESUME_GUEST_NV and this broke from the loop. > > This adds handling of RESUME_GUEST_NV in kvmppc_vcpu_run_hv(). > > Cc: Michael S. Tsirkin <mst@redhat.com> > Suggested-by: Paul Mackerras <paulus@samba.org> > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> > --- > > This definitely needs a better commit message. Please, help. > ps. it seems like ioeventfd never worked on ppc64. hm. > > --- > arch/powerpc/kvm/book3s_hv.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c > index 072287f..24f363f 100644 > --- a/arch/powerpc/kvm/book3s_hv.c > +++ b/arch/powerpc/kvm/book3s_hv.c > @@ -1569,7 +1569,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) > vcpu->arch.fault_dar, vcpu->arch.fault_dsisr); > srcu_read_unlock(&vcpu->kvm->srcu, srcu_idx); > } > - } while (r == RESUME_GUEST); > + } while ((r == RESUME_GUEST_NV) || (r == RESUME_GUEST)); How about while(!(r & RESUME_FLAG_HOST)); That should cover all RESUME_GUEST_XXX cases just fine. Apart from that I agree that we should check for ! FLAG_HOST bit rather than the actual RESUME_GUEST value in all case where we check for it (read: please update all places). Alex -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 01/13/2014 02:44 AM, Alexander Graf wrote: > > On 10.01.2014, at 08:21, Alexey Kardashevskiy <aik@ozlabs.ru> wrote: > >> When write to MMIO happens and there is an ioeventfd for that and >> is handled successfully, ioeventfd_write() returns 0 (success) and >> kvmppc_handle_store() returns EMULATE_DONE. Then kvmppc_emulate_mmio() >> converts EMULATE_DONE to RESUME_GUEST_NV and this broke from the loop. >> >> This adds handling of RESUME_GUEST_NV in kvmppc_vcpu_run_hv(). >> >> Cc: Michael S. Tsirkin <mst@redhat.com> >> Suggested-by: Paul Mackerras <paulus@samba.org> >> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> >> --- >> >> This definitely needs a better commit message. Please, help. >> ps. it seems like ioeventfd never worked on ppc64. hm. >> >> --- >> arch/powerpc/kvm/book3s_hv.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c >> index 072287f..24f363f 100644 >> --- a/arch/powerpc/kvm/book3s_hv.c >> +++ b/arch/powerpc/kvm/book3s_hv.c >> @@ -1569,7 +1569,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) >> vcpu->arch.fault_dar, vcpu->arch.fault_dsisr); >> srcu_read_unlock(&vcpu->kvm->srcu, srcu_idx); >> } >> - } while (r == RESUME_GUEST); >> + } while ((r == RESUME_GUEST_NV) || (r == RESUME_GUEST)); > > How about > > while(!(r & RESUME_FLAG_HOST)); Rather "while(!(r & RESUME_FLAG_HOST) && (r > 0));" and still not obvious that this is really better. Paul agrees with the original patch (and made a better commit message for our internal tree) but I just cannot make him reply in this thread, keep constantly asking him but to no avail :) > That should cover all RESUME_GUEST_XXX cases just fine. Apart from that > I agree that we should check for ! FLAG_HOST bit rather than the actual > RESUME_GUEST value in all case where we check for it (read: please > update all places). There are 3 places remotely similar to this and none of them requires a fix like above.
On 04.02.2014, at 09:03, Alexey Kardashevskiy <aik@ozlabs.ru> wrote: > On 01/13/2014 02:44 AM, Alexander Graf wrote: >> >> On 10.01.2014, at 08:21, Alexey Kardashevskiy <aik@ozlabs.ru> wrote: >> >>> When write to MMIO happens and there is an ioeventfd for that and >>> is handled successfully, ioeventfd_write() returns 0 (success) and >>> kvmppc_handle_store() returns EMULATE_DONE. Then kvmppc_emulate_mmio() >>> converts EMULATE_DONE to RESUME_GUEST_NV and this broke from the loop. >>> >>> This adds handling of RESUME_GUEST_NV in kvmppc_vcpu_run_hv(). >>> >>> Cc: Michael S. Tsirkin <mst@redhat.com> >>> Suggested-by: Paul Mackerras <paulus@samba.org> >>> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> >>> --- >>> >>> This definitely needs a better commit message. Please, help. >>> ps. it seems like ioeventfd never worked on ppc64. hm. >>> >>> --- >>> arch/powerpc/kvm/book3s_hv.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c >>> index 072287f..24f363f 100644 >>> --- a/arch/powerpc/kvm/book3s_hv.c >>> +++ b/arch/powerpc/kvm/book3s_hv.c >>> @@ -1569,7 +1569,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) >>> vcpu->arch.fault_dar, vcpu->arch.fault_dsisr); >>> srcu_read_unlock(&vcpu->kvm->srcu, srcu_idx); >>> } >>> - } while (r == RESUME_GUEST); >>> + } while ((r == RESUME_GUEST_NV) || (r == RESUME_GUEST)); >> >> How about >> >> while(!(r & RESUME_FLAG_HOST)); > > > Rather "while(!(r & RESUME_FLAG_HOST) && (r > 0));" and still not obvious > that this is really better. > > Paul agrees with the original patch (and made a better commit message for > our internal tree) but I just cannot make him reply in this thread, keep > constantly asking him but to no avail :) > > >> That should cover all RESUME_GUEST_XXX cases just fine. Apart from that >> I agree that we should check for ! FLAG_HOST bit rather than the actual >> RESUME_GUEST value in all case where we check for it (read: please >> update all places). > > There are 3 places remotely similar to this and none of them requires a fix > like above. Not today. Then someone goes in and realizes that CEDE advanced version 8 should clear r15 at which point you have to set RESUME_GUEST_NV and are in the same mess again. Let's just always treat RESUME_GUEST_NV and RESUME_GUEST as identical when checking for it. If you like, add a small helper like static inline bool is_resume_guest(int r) { return (r == RESUME_GUEST || r == RESUME_GUEST_NV); } in a header and use that one instead. That way we're guaranteed to be consistent. Alex -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 072287f..24f363f 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -1569,7 +1569,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) vcpu->arch.fault_dar, vcpu->arch.fault_dsisr); srcu_read_unlock(&vcpu->kvm->srcu, srcu_idx); } - } while (r == RESUME_GUEST); + } while ((r == RESUME_GUEST_NV) || (r == RESUME_GUEST)); out: vcpu->arch.state = KVMPPC_VCPU_NOTREADY;
When write to MMIO happens and there is an ioeventfd for that and is handled successfully, ioeventfd_write() returns 0 (success) and kvmppc_handle_store() returns EMULATE_DONE. Then kvmppc_emulate_mmio() converts EMULATE_DONE to RESUME_GUEST_NV and this broke from the loop. This adds handling of RESUME_GUEST_NV in kvmppc_vcpu_run_hv(). Cc: Michael S. Tsirkin <mst@redhat.com> Suggested-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> --- This definitely needs a better commit message. Please, help. ps. it seems like ioeventfd never worked on ppc64. hm. --- arch/powerpc/kvm/book3s_hv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)