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 D1166219E0; Mon, 23 Jun 2025 13:18:45 +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=1750684725; cv=none; b=QiHEruheS23dZpnN+nQTazY0ABtzBCwrVjslb14Vh5WuIBmpuqRWac7EwQ/0Pu2a+kK4yfIuZJsmdU5DlL52ZPQsQWnsCSXJAnhayh9F6RxHdcrKo/c2Bjvqgg17rgEXh4a3onoK6m21P7EAogfDui8oy+faca8zHeV4hgjVKxI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750684725; c=relaxed/simple; bh=IgW28ZByBE1hX0H6jVIs7eA+vQ81JXfS6Tmhlz8DR4E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kYe30kCoU5rcD524UFQxEYVdN8JfFp9+HwNwB0fD51EUuG5tyi6bT51LKT3lp9aIuvoHUWU5xA7hktQC9kLPG7ygs5d9twyAe1AaM0XAc6GFk8q3s5+MYn40FyxkwmWl7CrPhxyN/pBiPADisGxgzlL5oBFoJ5uucEESELRAv3U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jFcXMIGW; 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="jFcXMIGW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0D2A1C4CEEA; Mon, 23 Jun 2025 13:18:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750684725; bh=IgW28ZByBE1hX0H6jVIs7eA+vQ81JXfS6Tmhlz8DR4E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jFcXMIGWsmlIsAg8nsjplPLgJtrjNAORRygbc6hGU6ME38VEXc3qHec6AHJFZ3DGt J5mX7QO+cuYRWmX1WhwypFl1OKG75TmBHM6c+PxXWZUwnRylhv5hNN9jDLJWjlyvHR K/z9jes0gmSvLXF6Y3LrztEkERqomYIcots75yfo= 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 5.4 016/222] x86/mtrr: Check if fixed-range MTRRs exist in mtrr_save_fixed_ranges() Date: Mon, 23 Jun 2025 15:05:51 +0200 Message-ID: <20250623130612.390964915@linuxfoundation.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250623130611.896514667@linuxfoundation.org> References: <20250623130611.896514667@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-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 4ea906fe1c351..d15152126877b 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -350,7 +350,7 @@ 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