From mboxrd@z Thu Jan 1 00:00:00 1970 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AB577C8303C for ; Fri, 11 Jul 2025 07:45:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=uKzGV8OnV+hp4DpvDUPLtngn7PJUqAAJsVZSE9Zn1Es=; b=NVOVx5jiWnrJuGkndZYH5gzcAR wI7zuKkHwH+r1UHRzTc38Ph+3afnhj1pVbsDlODm7xWdXKjDz+rza3cKhYxA9ra/r1Q0JHk2Y59l8 FOJSOa4cXcRujk2uBHUbwjnukV88JYEkVEcoclsvQ4uBBg2mg1gWXHOp+LH938e23BuY9tVJ537dX VNcKZ74c566c0BuCESntjVGdrtdvS6QqtlIzhd5R0+yQBfVeMREs3NGpIuuEPCWDeAcyX/WFT1+Wm 0g7Rl4IUkKONEsP1RDbaeWKITBP2QfTA+D/QARAM3uUGik9EC/HgFXLs9VKTwxqizJBWn4ZKF+eVH iwUivGaw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ua8S2-0000000E1Gx-32I4; Fri, 11 Jul 2025 07:45:46 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1ua8Ao-0000000DyLe-2ou9 for linux-arm-kernel@lists.infradead.org; Fri, 11 Jul 2025 07:27:59 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id EF0C4444B3; Fri, 11 Jul 2025 07:27:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F0814C4CEED; Fri, 11 Jul 2025 07:27:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752218877; bh=1j6zpFS1DVxWS1hxIV2/OdRNBhbPf+kJqE3FRm4cKC4=; h=From:To:Cc:Subject:Date:From; b=d0OLdVU4WW5AyI7Qx0K6WV7vTsCe8RYod5bHaEglGd68ShyZuQBsiCZKJbvDq8fG5 /3rgIEMyKy/WVzx8LSE8c6JPNA9uwUr0p6mu7IKoGE7CalIEjtnquG9JmrjiXlGJde 4kGmdSSbclD4AHFyAjRqLLHVDZI35/MEDvivwPaDcZo16v1dqpKqcBLNYnuz+iU8Gz W1JiLAd+rki6nEXs4bOzc1J8ppdazvdGKhfan6USczkBV8AqEMm4ETus9uh1Uihc7n O4xSnlwpG6n9H64HA3voGAMTgvH1zLlPva4hY+BUuS/jcbsaT+Lkq0lUN2GlxzfQJg WigyTZS+XaRaQ== From: Arnd Bergmann To: Marc Zyngier , Oliver Upton , Catalin Marinas , Will Deacon Cc: Arnd Bergmann , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Mark Brown , James Morse , Sebastian Ott , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH] KVM: arm64: fix u64_replace_bits() usage Date: Fri, 11 Jul 2025 09:27:47 +0200 Message-Id: <20250711072752.2781647-1-arnd@kernel.org> X-Mailer: git-send-email 2.39.5 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250711_002758_736022_795886C9 X-CRM114-Status: GOOD ( 12.83 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann u64_replace_bits() returns a modified word but does not actually modify its argument, as pointed out by this new warning: arch/arm64/kvm/sys_regs.c: In function 'access_mdcr': arch/arm64/kvm/sys_regs.c:2654:17: error: ignoring return value of 'u64_replace_bits' declared with attribute 'warn_unused_result' [-Werror=unused-result] 2654 | u64_replace_bits(val, hpmn, MDCR_EL2_HPMN); The intention here must have been to update 'val', so do that instead. Fixes: efff9dd2fee7 ("KVM: arm64: Handle out-of-bound write to MDCR_EL2.HPMN") Signed-off-by: Arnd Bergmann --- 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 33aa4f5071b8..793fb19bebd6 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2651,7 +2651,7 @@ 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); + val = u64_replace_bits(val, hpmn, MDCR_EL2_HPMN); } __vcpu_assign_sys_reg(vcpu, MDCR_EL2, val); -- 2.39.5