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 E32CD2248B5; Mon, 23 Jun 2025 22:10:17 +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=1750716618; cv=none; b=Xg3AKe4KeGu1pzGeXOHj/v6gi3pCDRumPdfbpWRj9JuPDkDXZx9Ubajf/u6FX5dhK3i1Y+/e8P/cRc7e+XXu8zPgxJyOx2ot52wEeT0+HdpOdftxgn5bYtSbZxlTvfMkPi42Q//5LxRDNfCfrth4VIacZsLXk2iP43QtHmTIrb4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750716618; c=relaxed/simple; bh=DaMm2dNahzbWe8RjJo3yg5MY6qwHl77uROC0G1BAqJY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LQwXpRuWl5q4SvXPUSKOYxWzbEkc2nMZP3zhrp+/deI/Fjp/kzs3FCUfUIBg363QSOvheS3Z5JRf8g1OBNGW7wCYrf5Q1ipjbEhQAfBHHW9GFka5dCKgVD8IoTGJOzFpNv6EGHDxKqzML/KfDHgjzFNF6fsTr/6ksCwn/HTYijo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oVNCeclN; 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="oVNCeclN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7E368C4CEEA; Mon, 23 Jun 2025 22:10:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750716617; bh=DaMm2dNahzbWe8RjJo3yg5MY6qwHl77uROC0G1BAqJY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oVNCeclNnoQ3cekMCFP23r/FzJX28AcZ0fOYCXaV0l/Mai+TJuHzZwPQSZsLTpYwZ HwT9L9u/ZL+e2CziiYQ3zvsgJ38R9FkkQio4Dyio1VWDshu1RCsfa8JpPldLynuzK0 M5VN7kfs2/6M5hVeXCcpTPFi0ZSVAlsKHoSdbaNs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, David.Kaplan@amd.com, peterz@infradead.org, pawan.kumar.gupta@linux.intel.com, mingo@kernel.org, brad.spengler@opensrcsec.com, Salvatore Bonaccorso , Breno Leitao Subject: [PATCH 5.15 345/411] Revert "x86/bugs: Make spectre user default depend on MITIGATION_SPECTRE_V2" on v6.6 and older Date: Mon, 23 Jun 2025 15:08:09 +0200 Message-ID: <20250623130642.332564164@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: Breno Leitao This reverts commit 4fc2d289b3cc4cf23ccabe59cf936d1dc49aeda8 which is commit 98fdaeb296f51ef08e727a7cc72e5b5c864c4f4d upstream. commit 7adb96687ce8 ("x86/bugs: Make spectre user default depend on MITIGATION_SPECTRE_V2") depends on commit 72c70f480a70 ("x86/bugs: Add a separate config for Spectre V2"), which introduced MITIGATION_SPECTRE_V2. commit 72c70f480a70 ("x86/bugs: Add a separate config for Spectre V2") never landed in stable tree, thus, stable tree doesn't have MITIGATION_SPECTRE_V2, that said, commit 7adb96687ce8 ("x86/bugs: Make spectre user default depend on MITIGATION_SPECTRE_V2") has no value if the dependecy was not applied. Revert commit 7adb96687ce8 ("x86/bugs: Make spectre user default depend on MITIGATION_SPECTRE_V2") in stable kernel which landed in in 5.4.294, 5.10.238, 5.15.185, 6.1.141 and 6.6.93 stable versions. Cc: David.Kaplan@amd.com Cc: peterz@infradead.org Cc: pawan.kumar.gupta@linux.intel.com Cc: mingo@kernel.org Cc: brad.spengler@opensrcsec.com Cc: stable@vger.kernel.org # 6.6 6.1 5.15 5.10 5.4 Reported-by: Brad Spengler Reported-by: Salvatore Bonaccorso Signed-off-by: Breno Leitao Signed-off-by: Greg Kroah-Hartman --- Documentation/admin-guide/kernel-parameters.txt | 2 -- arch/x86/kernel/cpu/bugs.c | 10 +++------- 2 files changed, 3 insertions(+), 9 deletions(-) --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5445,8 +5445,6 @@ Selecting 'on' will also enable the mitigation against user space to user space task attacks. - Selecting specific mitigation does not force enable - user mitigations. Selecting 'off' will disable both the kernel and the user space protections. --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1382,13 +1382,9 @@ static __ro_after_init enum spectre_v2_m static enum spectre_v2_user_cmd __init spectre_v2_parse_user_cmdline(void) { - enum spectre_v2_user_cmd mode; char arg[20]; int ret, i; - mode = IS_ENABLED(CONFIG_MITIGATION_SPECTRE_V2) ? - SPECTRE_V2_USER_CMD_AUTO : SPECTRE_V2_USER_CMD_NONE; - switch (spectre_v2_cmd) { case SPECTRE_V2_CMD_NONE: return SPECTRE_V2_USER_CMD_NONE; @@ -1401,7 +1397,7 @@ spectre_v2_parse_user_cmdline(void) ret = cmdline_find_option(boot_command_line, "spectre_v2_user", arg, sizeof(arg)); if (ret < 0) - return mode; + return SPECTRE_V2_USER_CMD_AUTO; for (i = 0; i < ARRAY_SIZE(v2_user_options); i++) { if (match_option(arg, ret, v2_user_options[i].option)) { @@ -1411,8 +1407,8 @@ spectre_v2_parse_user_cmdline(void) } } - pr_err("Unknown user space protection option (%s). Switching to default\n", arg); - return mode; + pr_err("Unknown user space protection option (%s). Switching to AUTO select\n", arg); + return SPECTRE_V2_USER_CMD_AUTO; } static inline bool spectre_v2_in_eibrs_mode(enum spectre_v2_mitigation mode)