| Message ID | 1495123889-32301-1-git-send-email-wei@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 18 May 2017 at 17:11, Wei Huang <wei@redhat.com> wrote: > The PMUv3 driver of linux kernel (in arch/arm64/kernel/perf_event.c) > relies on the PMUVER field of id_aa64dfr0_el1 to decide if PMU support > is present or not. This patch clears the PMUVER field under TCG mode > when vPMU=off. Without it, PMUv3 will init insider guest VMs even > with vPMU=off. This patch also removes a redundant line inside the > if-statement. > > Signed-off-by: Wei Huang <wei@redhat.com> > --- > target/arm/cpu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/target/arm/cpu.c b/target/arm/cpu.c > index c185eb1..4e8fe1c 100644 > --- a/target/arm/cpu.c > +++ b/target/arm/cpu.c > @@ -750,8 +750,8 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp) > } > > if (!cpu->has_pmu) { > - cpu->has_pmu = false; > unset_feature(env, ARM_FEATURE_PMU); > + cpu->id_aa64dfr0 &= ~0xf00; > } > > if (!arm_feature(env, ARM_FEATURE_EL2)) { > -- > 1.8.3.1 Applied to target-arm.next, thanks. -- PMM
diff --git a/target/arm/cpu.c b/target/arm/cpu.c index c185eb1..4e8fe1c 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -750,8 +750,8 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp) } if (!cpu->has_pmu) { - cpu->has_pmu = false; unset_feature(env, ARM_FEATURE_PMU); + cpu->id_aa64dfr0 &= ~0xf00; } if (!arm_feature(env, ARM_FEATURE_EL2)) {
The PMUv3 driver of linux kernel (in arch/arm64/kernel/perf_event.c) relies on the PMUVER field of id_aa64dfr0_el1 to decide if PMU support is present or not. This patch clears the PMUVER field under TCG mode when vPMU=off. Without it, PMUv3 will init insider guest VMs even with vPMU=off. This patch also removes a redundant line inside the if-statement. Signed-off-by: Wei Huang <wei@redhat.com> --- target/arm/cpu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)