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 D1DBE2550A4; Mon, 23 Jun 2025 13:28:15 +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=1750685295; cv=none; b=oeq/wkfy6TFRdFeeGp2C9fHYWO3Ehx61Nl2BijCmVMzf9LKYBezsKPbs9xZIz9LJlL9N0TOQ+rkv95yTjaFCgI3mgN2YAWL1mFvbuMctAnbo4siPImpJ/Ek2K3tAfg64ULMs+KZp9pT8z7sZKlsM/S+eTTJ3B0lP4ra+xPVtnNg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750685295; c=relaxed/simple; bh=5BAEjZyksUoWft7iFwVzBkp6F82fLJqW6KCtGZHx1m8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hrB3K7heGAf/kTbNHYeq9FlBWGgYKiJzGwrel2E2TvRGBUrSAjoWL9zviuof2SFyccvGEr+14p1iaMfCBCERSDdXYQHOXtmMJZIwh2HLP54rfKHj88e/wTzymz5yU4DgC2IKj+U5sXmM5swDMMhGh8+yCF7gFiq/tbVxoxK9kyY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=M+on9S0B; 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="M+on9S0B" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60AACC4CEF1; Mon, 23 Jun 2025 13:28:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750685295; bh=5BAEjZyksUoWft7iFwVzBkp6F82fLJqW6KCtGZHx1m8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M+on9S0BI58UJFRgG63ErDRgGp2m+joC3Tweqxv47u2PjNWC8pzrtC2t/I46nKxdn cD59N9c9S0SsLvGpQOLax4Op/v9CUQy0hHQulCJaTjIKDtUDLkPTMZJH4yFhgqDx/L 7hm9kI715HvCqeL+9dylFh7I48RdGXoufERoo3dQ= 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 5.15 024/411] x86/mtrr: Check if fixed-range MTRRs exist in mtrr_save_fixed_ranges() Date: Mon, 23 Jun 2025 15:02:48 +0200 Message-ID: <20250623130633.729541120@linuxfoundation.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250623130632.993849527@linuxfoundation.org> References: <20250623130632.993849527@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 5.15-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 558108296f3cf..31549e7f6b7c6 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -349,7 +349,7 @@ 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