[PATCH v2 1/2] KVM: arm64: Fix enforcement of upper bound on MDCR_EL2.HPMN
From: Ben Horgan <ben.horgan@arm.com>
Date: 2025-07-09 09:38:24
Also in:
kvmarm, lkml, stable
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
Previously, u64_replace_bits() was used to no effect as the return value
was ignored. Convert to u64p_replace_bits() so the value is updated in
place.
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Ben Horgan <ben.horgan@arm.com>
Fixes: efff9dd2fee7 ("KVM: arm64: Handle out-of-bound write to MDCR_EL2.HPMN")
Cc: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
---
arch/arm64/kvm/sys_regs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 76c2f0da821f..c20bd6f21e60 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c@@ -2624,7 +2624,7 @@ static bool access_mdcr(struct kvm_vcpu *vcpu, */ if (hpmn > vcpu->kvm->arch.nr_pmu_counters) { hpmn = vcpu->kvm->arch.nr_pmu_counters; - u64_replace_bits(val, hpmn, MDCR_EL2_HPMN); + u64p_replace_bits(&val, hpmn, MDCR_EL2_HPMN); } __vcpu_assign_sys_reg(vcpu, MDCR_EL2, val);
--
2.43.0