Hi Greg,
This is an adjustment of the original upstream patch aimed towards the
4.19.y stable branch.
Thank you.
Raghavendra
On Thu, Dec 12, 2024 at 12:27 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Tue, Dec 03, 2024 at 07:02:36PM +0000, Raghavendra Rao Ananta wrote:
> > commit 54bbee190d42166209185d89070c58a343bf514b upstream.
> >
> > DDI0487K.a D13.3.1 describes the PMU overflow condition, which evaluates
> > to true if any counter's global enable (PMCR_EL0.E), overflow flag
> > (PMOVSSET_EL0[n]), and interrupt enable (PMINTENSET_EL1[n]) are all 1.
> > Of note, this does not require a counter to be enabled
> > (i.e. PMCNTENSET_EL0[n] = 1) to generate an overflow.
> >
> > Align kvm_pmu_overflow_status() with the reality of the architecture
> > and stop using PMCNTENSET_EL0 as part of the overflow condition. The
> > bug was discovered while running an SBSA PMU test [*], which only sets
> > PMCR.E, PMOVSSET<0>, PMINTENSET<0>, and expects an overflow interrupt.
> >
> > Cc: stable@xxxxxxxxxxxxxxx
> > Fixes: 76d883c4e640 ("arm64: KVM: Add access handler for PMOVSSET and PMOVSCLR register")
> > Link: https://github.com/ARM-software/sbsa-acs/blob/master/test_pool/pmu/operating_system/test_pmu001.c
> > Signed-off-by: Raghavendra Rao Ananta <rananta@xxxxxxxxxx>
> > [ oliver: massaged changelog ]
> > Reviewed-by: Marc Zyngier <maz@xxxxxxxxxx>
> > Link: https://lore.kernel.org/r/20241120005230.2335682-2-oliver.upton@xxxxxxxxx
> > Signed-off-by: Oliver Upton <oliver.upton@xxxxxxxxx>
> > ---
> > virt/kvm/arm/pmu.c | 1 -
> > 1 file changed, 1 deletion(-)
>
> What kernel branch(es) is this backport for?
