FAILED: patch "[PATCH] KVM: arm64: Ignore PMCNTENSET_EL0 while checking for overflow" failed to apply to 4.19-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 54bbee190d42166209185d89070c58a343bf514b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024120223-stunner-letter-9d09@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 54bbee190d42166209185d89070c58a343bf514b Mon Sep 17 00:00:00 2001
From: Raghavendra Rao Ananta <rananta@google.com>
Date: Tue, 19 Nov 2024 16:52:29 -0800
Subject: [PATCH] KVM: arm64: Ignore PMCNTENSET_EL0 while checking for overflow
 status

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@vger.kernel.org
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@google.com>
[ oliver: massaged changelog ]
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241120005230.2335682-2-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index 8ad62284fa23..3855cc9d0ca5 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c
@@ -381,7 +381,6 @@ static u64 kvm_pmu_overflow_status(struct kvm_vcpu *vcpu)
 
 	if ((kvm_vcpu_read_pmcr(vcpu) & ARMV8_PMU_PMCR_E)) {
 		reg = __vcpu_sys_reg(vcpu, PMOVSSET_EL0);
-		reg &= __vcpu_sys_reg(vcpu, PMCNTENSET_EL0);
 		reg &= __vcpu_sys_reg(vcpu, PMINTENSET_EL1);
 	}