From nobody Thu Sep 18 04:19:26 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F14CFC04FDE for ; Fri, 9 Dec 2022 16:45:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229722AbiLIQpS (ORCPT ); Fri, 9 Dec 2022 11:45:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39884 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229631AbiLIQpO (ORCPT ); Fri, 9 Dec 2022 11:45:14 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id D47102EF22 for ; Fri, 9 Dec 2022 08:45:13 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 68027D6E; Fri, 9 Dec 2022 08:45:20 -0800 (PST) Received: from e126815.warwick.arm.com (e126815.arm.com [10.32.32.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E3C1A3F73D; Fri, 9 Dec 2022 08:45:11 -0800 (PST) From: James Clark To: kvmarm@lists.linux.dev Cc: James Clark , Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , Oliver Upton , Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org Subject: [PATCH 1/1] KVM: arm64: PMU: Fix PMCR_EL0 reset value Date: Fri, 9 Dec 2022 16:44:46 +0000 Message-Id: <20221209164446.1972014-2-james.clark@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221209164446.1972014-1-james.clark@arm.com> References: <20221209164446.1972014-1-james.clark@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" ARMV8_PMU_PMCR_N_MASK is an unshifted value which results in the wrong reset value for PMCR_EL0, so shift it to fix it. This fixes the following error when running qemu: $ qemu-system-aarch64 -cpu host -machine type=3Dvirt,accel=3Dkvm -kernel = ... target/arm/helper.c:1813: pmevcntr_rawwrite: Assertion `counter < pmu_num= _counters(env)' failed. Fixes: 292e8f149476 ("KVM: arm64: PMU: Simplify PMCR_EL0 reset handling") Signed-off-by: James Clark Reviewed-by: Oliver Upton --- 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 d5ee52d6bf73..c6cbfe6b854b 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -646,7 +646,7 @@ static void reset_pmcr(struct kvm_vcpu *vcpu, const str= uct sys_reg_desc *r) return; =20 /* Only preserve PMCR_EL0.N, and reset the rest to 0 */ - pmcr =3D read_sysreg(pmcr_el0) & ARMV8_PMU_PMCR_N_MASK; + pmcr =3D read_sysreg(pmcr_el0) & (ARMV8_PMU_PMCR_N_MASK << ARMV8_PMU_PMCR= _N_SHIFT); if (!kvm_supports_32bit_el0()) pmcr |=3D ARMV8_PMU_PMCR_LC; =20 --=20 2.25.1