Message ID | 20180111185538.GI15307@cbox (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Hi Christoffer On 11/01/18 19:55, Christoffer Dall wrote: > On Mon, Jan 08, 2018 at 10:52:54AM +0100, Eric Auger wrote: >> Commit 3d1ad640f8c94 ("KVM: arm/arm64: Fix GICv4 ITS initialization >> issues") moved the vgic_supports_direct_msis() check in vgic_v4_init(). >> However when vgic_v4_init is called from vgic_its_create(), the has_its >> field is not yet set. Hence vgic_supports_direct_msis returns false and >> vgic_v4_init does nothing. >> >> Let's move the check back to vgic_v4_init caller. >> >> Fixes: 3d1ad640f8c94 ("KVM: arm/arm64: Fix GICv4 ITS initialization issues") >> Signed-off-by: Eric Auger <eric.auger@redhat.com> >> >> --- >> >> v1 -> v2: >> - move the check to the caller > > Why this change, I slightly preferred the first version of this patch, > but I will admit that the "has_its = true; no_wait(); has_its = false;" > things is pretty ugly... I didn't find the 1st solution elegant either and reverted to how the code looked like before your patch. > >> - identify the right commit this patch fixes >> --- >> virt/kvm/arm/vgic/vgic-init.c | 8 +++++--- >> virt/kvm/arm/vgic/vgic-its.c | 2 +- >> virt/kvm/arm/vgic/vgic-v4.c | 3 --- >> 3 files changed, 6 insertions(+), 7 deletions(-) >> >> diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c >> index 6231012..40be908 100644 >> --- a/virt/kvm/arm/vgic/vgic-init.c >> +++ b/virt/kvm/arm/vgic/vgic-init.c >> @@ -285,9 +285,11 @@ int vgic_init(struct kvm *kvm) >> if (ret) >> goto out; >> >> - ret = vgic_v4_init(kvm); >> - if (ret) >> - goto out; >> + if (vgic_supports_direct_msis(kvm)) { >> + ret = vgic_v4_init(kvm); >> + if (ret) >> + goto out; >> + } >> >> kvm_for_each_vcpu(i, vcpu, kvm) >> kvm_vgic_vcpu_enable(vcpu); >> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c >> index 8e633bd..aebc88d 100644 >> --- a/virt/kvm/arm/vgic/vgic-its.c >> +++ b/virt/kvm/arm/vgic/vgic-its.c >> @@ -1687,7 +1687,7 @@ static int vgic_its_create(struct kvm_device *dev, u32 type) >> if (!its) >> return -ENOMEM; >> >> - if (vgic_initialized(dev->kvm)) { >> + if (kvm_vgic_global_state.has_gicv4 && vgic_initialized(dev->kvm)) { > > ... but now we're using vgic_supports_direct_msis() in one part of the > init path and a half-open coded version of that in another path, which > is not very pretty. > > So I actually would suggest doing the init stuff more open-coded, > because init of the gic/its/gicv4 is a mess anyway. > > Something like this: > > diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c > index 62310122ee78..743ca5cb05ef 100644 > --- a/virt/kvm/arm/vgic/vgic-init.c > +++ b/virt/kvm/arm/vgic/vgic-init.c > @@ -285,9 +285,11 @@ int vgic_init(struct kvm *kvm) > if (ret) > goto out; > > - ret = vgic_v4_init(kvm); > - if (ret) > - goto out; > + if (vgic_has_its(kvm)) { > + ret = vgic_v4_init(kvm); > + if (ret) > + goto out; > + } > > kvm_for_each_vcpu(i, vcpu, kvm) > kvm_vgic_vcpu_enable(vcpu); > diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c > index 4a37292855bc..bc4265154bac 100644 > --- a/virt/kvm/arm/vgic/vgic-v4.c > +++ b/virt/kvm/arm/vgic/vgic-v4.c > @@ -118,7 +118,7 @@ int vgic_v4_init(struct kvm *kvm) > struct kvm_vcpu *vcpu; > int i, nr_vcpus, ret; > > - if (!vgic_supports_direct_msis(kvm)) > + if (!kvm_vgic_global_state.has_gicv4) > return 0; /* Nothing to see here... move along. */ > > if (dist->its_vm.vpes) > > Does that work? Looks OK to me. Unfortunately I don't have access to this specific machine anymore at the moment so I can't test it right now. Thanks Eric > > Thanks, > -Christoffer >
On Fri, Jan 12, 2018 at 08:45:31AM +0100, Auger Eric wrote: > Hi Christoffer > > On 11/01/18 19:55, Christoffer Dall wrote: > > On Mon, Jan 08, 2018 at 10:52:54AM +0100, Eric Auger wrote: > >> Commit 3d1ad640f8c94 ("KVM: arm/arm64: Fix GICv4 ITS initialization > >> issues") moved the vgic_supports_direct_msis() check in vgic_v4_init(). > >> However when vgic_v4_init is called from vgic_its_create(), the has_its > >> field is not yet set. Hence vgic_supports_direct_msis returns false and > >> vgic_v4_init does nothing. > >> > >> Let's move the check back to vgic_v4_init caller. > >> > >> Fixes: 3d1ad640f8c94 ("KVM: arm/arm64: Fix GICv4 ITS initialization issues") > >> Signed-off-by: Eric Auger <eric.auger@redhat.com> > >> > >> --- > >> > >> v1 -> v2: > >> - move the check to the caller > > > > Why this change, I slightly preferred the first version of this patch, > > but I will admit that the "has_its = true; no_wait(); has_its = false;" > > things is pretty ugly... > > I didn't find the 1st solution elegant either and reverted to how the > code looked like before your patch. > > > >> - identify the right commit this patch fixes > >> --- > >> virt/kvm/arm/vgic/vgic-init.c | 8 +++++--- > >> virt/kvm/arm/vgic/vgic-its.c | 2 +- > >> virt/kvm/arm/vgic/vgic-v4.c | 3 --- > >> 3 files changed, 6 insertions(+), 7 deletions(-) > >> > >> diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c > >> index 6231012..40be908 100644 > >> --- a/virt/kvm/arm/vgic/vgic-init.c > >> +++ b/virt/kvm/arm/vgic/vgic-init.c > >> @@ -285,9 +285,11 @@ int vgic_init(struct kvm *kvm) > >> if (ret) > >> goto out; > >> > >> - ret = vgic_v4_init(kvm); > >> - if (ret) > >> - goto out; > >> + if (vgic_supports_direct_msis(kvm)) { > >> + ret = vgic_v4_init(kvm); > >> + if (ret) > >> + goto out; > >> + } > >> > >> kvm_for_each_vcpu(i, vcpu, kvm) > >> kvm_vgic_vcpu_enable(vcpu); > >> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > >> index 8e633bd..aebc88d 100644 > >> --- a/virt/kvm/arm/vgic/vgic-its.c > >> +++ b/virt/kvm/arm/vgic/vgic-its.c > >> @@ -1687,7 +1687,7 @@ static int vgic_its_create(struct kvm_device *dev, u32 type) > >> if (!its) > >> return -ENOMEM; > >> > >> - if (vgic_initialized(dev->kvm)) { > >> + if (kvm_vgic_global_state.has_gicv4 && vgic_initialized(dev->kvm)) { > > > > ... but now we're using vgic_supports_direct_msis() in one part of the > > init path and a half-open coded version of that in another path, which > > is not very pretty. > > > > So I actually would suggest doing the init stuff more open-coded, > > because init of the gic/its/gicv4 is a mess anyway. > > > > Something like this: > > > > diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c > > index 62310122ee78..743ca5cb05ef 100644 > > --- a/virt/kvm/arm/vgic/vgic-init.c > > +++ b/virt/kvm/arm/vgic/vgic-init.c > > @@ -285,9 +285,11 @@ int vgic_init(struct kvm *kvm) > > if (ret) > > goto out; > > > > - ret = vgic_v4_init(kvm); > > - if (ret) > > - goto out; > > + if (vgic_has_its(kvm)) { > > + ret = vgic_v4_init(kvm); > > + if (ret) > > + goto out; > > + } > > > > kvm_for_each_vcpu(i, vcpu, kvm) > > kvm_vgic_vcpu_enable(vcpu); > > diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c > > index 4a37292855bc..bc4265154bac 100644 > > --- a/virt/kvm/arm/vgic/vgic-v4.c > > +++ b/virt/kvm/arm/vgic/vgic-v4.c > > @@ -118,7 +118,7 @@ int vgic_v4_init(struct kvm *kvm) > > struct kvm_vcpu *vcpu; > > int i, nr_vcpus, ret; > > > > - if (!vgic_supports_direct_msis(kvm)) > > + if (!kvm_vgic_global_state.has_gicv4) > > return 0; /* Nothing to see here... move along. */ > > > > if (dist->its_vm.vpes) > > > > Does that work? > Looks OK to me. Unfortunately I don't have access to this specific > machine anymore at the moment so I can't test it right now. > ok, I've queued my version with your reported-by. Thanks, -Christoffer
diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c index 62310122ee78..743ca5cb05ef 100644 --- a/virt/kvm/arm/vgic/vgic-init.c +++ b/virt/kvm/arm/vgic/vgic-init.c @@ -285,9 +285,11 @@ int vgic_init(struct kvm *kvm) if (ret) goto out; - ret = vgic_v4_init(kvm); - if (ret) - goto out; + if (vgic_has_its(kvm)) { + ret = vgic_v4_init(kvm); + if (ret) + goto out; + } kvm_for_each_vcpu(i, vcpu, kvm) kvm_vgic_vcpu_enable(vcpu); diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c index 4a37292855bc..bc4265154bac 100644 --- a/virt/kvm/arm/vgic/vgic-v4.c +++ b/virt/kvm/arm/vgic/vgic-v4.c @@ -118,7 +118,7 @@ int vgic_v4_init(struct kvm *kvm) struct kvm_vcpu *vcpu; int i, nr_vcpus, ret; - if (!vgic_supports_direct_msis(kvm)) + if (!kvm_vgic_global_state.has_gicv4) return 0; /* Nothing to see here... move along. */ if (dist->its_vm.vpes)