From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E21C20F090; Tue, 17 Jun 2025 15:38:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750174704; cv=none; b=fPaQ2fufPKmE0FJnB1uuZHSpoCNmv/LkK/StaA8N23+t4wZtli00myUOuEoB7RJBaepboFuYGUIFWJBiNg1IVibnhj0+2n2tmHmVF/201qDylY7gH4/SA5iBlRBGBiAFC85gIyoGhesb9QB1e73udIEx1doHJf/ogqb5QgKy03o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750174704; c=relaxed/simple; bh=cxUsCSvQK5K4TuqAEArgS5Yqt4zFh1wR01mijHlAJps=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZMrIjRlFxDgAI/adL078OAePZEDSPvLH51wbT2quE/fTVHIKMnmSLetIEWGl6fwJ902tRIeB9laaDiS4OZqYO+qL2x806q7M1IDTKIwtt0+7FXq31VETym+Cd8utq+iiw4v3rE38PkvwWcO5taJFYJLhOQGpW+Dxq5c2jEoNLFE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=v9KzsEu8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="v9KzsEu8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E0CFC4CEE3; Tue, 17 Jun 2025 15:38:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750174704; bh=cxUsCSvQK5K4TuqAEArgS5Yqt4zFh1wR01mijHlAJps=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=v9KzsEu8M7HtcDK+RIZ0peNU+T3y19kBmL9mPhr0AZJr8m849fnP8HtbSzIc98yqS EZpEFW1w6F9lpOzJFtzprc/0LsKFSVcfQQKojxOOma25D/3KxAJ3j02trU09vdFPUq Pt90wG+6pFkC80XkcWRy5cSNxarqazbxAGSTspcA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jiaqing Zhao , "Borislav Petkov (AMD)" , Sasha Levin Subject: [PATCH 6.12 052/512] x86/mtrr: Check if fixed-range MTRRs exist in mtrr_save_fixed_ranges() Date: Tue, 17 Jun 2025 17:20:18 +0200 Message-ID: <20250617152421.643926260@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250617152419.512865572@linuxfoundation.org> References: <20250617152419.512865572@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiaqing Zhao [ Upstream commit 824c6384e8d9275d4ec7204f3f79a4ac6bc10379 ] When suspending, save_processor_state() calls mtrr_save_fixed_ranges() to save fixed-range MTRRs. On platforms without fixed-range MTRRs like the ACRN hypervisor which has removed fixed-range MTRR emulation, accessing these MSRs will trigger an unchecked MSR access error. Make sure fixed-range MTRRs are supported before access to prevent such error. Since mtrr_state.have_fixed is only set when MTRRs are present and enabled, checking the CPU feature flag in mtrr_save_fixed_ranges() is unnecessary. Fixes: 3ebad5905609 ("[PATCH] x86: Save and restore the fixed-range MTRRs of the BSP when suspending") Signed-off-by: Jiaqing Zhao Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/20250509170633.3411169-2-jiaqing.zhao@linux.intel.com Signed-off-by: Sasha Levin --- arch/x86/kernel/cpu/mtrr/generic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c index 7b29ebda024f4..1ececfce7a46a 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -591,7 +591,7 @@ static void get_fixed_ranges(mtrr_type *frs) void mtrr_save_fixed_ranges(void *info) { - if (boot_cpu_has(X86_FEATURE_MTRR)) + if (mtrr_state.have_fixed) get_fixed_ranges(mtrr_state.fixed_ranges); } -- 2.39.5