Re: [Qemu-devel] [PATCH 0/3] target/arm: pmu fixes

[Peter Maydell]

On Fri, 22 Mar 2019 at 16:23, Andrew Jones <address@hidden> wrote:
>
> The first two patches fix a regression I found when running
> the arm (as opposed to arm64) pmu kvm-unit-tests test on tcg,
>
>   $ git clone git://git.kernel.org/pub/scm/virt/kvm/kvm-unit-tests.git
>   $ cd kvm-unit-tests
>   $ ./configure --arch=arm --cross-prefix=arm-linux-gnu-
>   $ make -j
>   $ export QEMU=/path/to/qemu-system-arm or qemu-system-aarch64
>   $ arm/run arm/pmu.flat
>
> After checking the QEMU code I found it's also reproducible with
> the arm64 test if the PMU is removed,
>
>   $ ./configure --arch=arm64 --cross-prefix=aarch64-linux-gnu-
>   $ make -j
>   $ export QEMU=/path/to/qemu-system-aarch64
>   $ arm/run arm/pmu.flat -cpu cortex-a57,pmu=off
>
> Those tests used to pass, but now QEMU was crashing. I've broken
> the fix into two patches because the second patch is a bit of
> an RFC since I don't know if it's safe to enable all
> ARM_FEATURE_PMU code for PMUv2. Maybe that feature is only for
> PMUv3? This patch also enables the pmu cpu property to work with
> those cpu types, i.e. we can now do '-cpu cortex-a15,pmu=off' to
> remove the pmu. Although it wasn't clear to me if the PMU is
> optional (permitted to be removed) on those cpu types from the
> manuals.
>
> The last patch is just a trivial cleanup.
>
> Andrew Jones (3):
>   target/arm: fix crash on pmu register access
>   target/arm: cortex-a7 and cortex-a15 have pmus
>   target/arm: make pmccntr_op_start/finish static
>



Applied to target-arm.next, thanks.

-- PMM