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 674C72ECD33; Tue, 17 Jun 2025 15:49:37 +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=1750175377; cv=none; b=ovb5K5hXtMQT4FKmSXIZbflhDBJRro+QTPRO+rP0d6uWMn/gNDkVlGpIPx5uN5KUwbwLKC26oJ78a/2asw0XIoZiOdrKFWipTWjEUN1Sic4cTp6e/jUG+N7UwWszNX5lBAZi5/3dy2x8rXbZCNKPTGiV8M7YAY8C8H6kuAliEUc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750175377; c=relaxed/simple; bh=0rN6BOkuTqZ/eIWkjHtG6//Vgx6PbFPo1GNXOYA58LQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pqFr2h5hQNutLWPusNZkDpgPVLnuiyhubmqh0wkZYUdXXxjpKKPzGupBdEEoA37jqQ/w7YySOqja47Wq4sIr7pcgKblXzRaELg7xYciTtnefiqdFYKse3jCkXVIsbXryYIYHN2ej1bJX++pXNUVourr9cdf/K+dOn0MtBy8Hje8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hn2XQpUn; 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="hn2XQpUn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC017C4CEE3; Tue, 17 Jun 2025 15:49:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750175377; bh=0rN6BOkuTqZ/eIWkjHtG6//Vgx6PbFPo1GNXOYA58LQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hn2XQpUnaTkLGD4Aze3t+BspJmH05MC9fpnt0BE/kfzSMQsOjCLdNv7sWcUWgDwZe cYtiwFDYqm1HQj1iBpe8rKkxuc9LWKsG32hdt18rWAUykf4EdOL26c6AuplBhcIywl Eu8/7yuVSk8xhTmsOf0rEgmkYyooMY+D43XeyZio= 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 6.15 076/780] x86/mtrr: Check if fixed-range MTRRs exist in mtrr_save_fixed_ranges() Date: Tue, 17 Jun 2025 17:16:24 +0200 Message-ID: <20250617152454.605874811@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250617152451.485330293@linuxfoundation.org> References: <20250617152451.485330293@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 6.15-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 e2c6b471d2302..8c18327eb10bb 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -593,7 +593,7 @@ 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