From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 058D2C433EF for ; Mon, 25 Jul 2022 09:35:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233826AbiGYJfX (ORCPT ); Mon, 25 Jul 2022 05:35:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232235AbiGYJfV (ORCPT ); Mon, 25 Jul 2022 05:35:21 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB1299FED for ; Mon, 25 Jul 2022 02:35:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 89598B80E1B for ; Mon, 25 Jul 2022 09:35:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B3336C341CE; Mon, 25 Jul 2022 09:35:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658741716; bh=GSOjJiZXwZTkx1LpS0+LC8SqOhzW8WrKx65u/6LBXNc=; h=Subject:To:Cc:From:Date:From; b=mRULQRUiGMOtsaesK4lh1jTP0AYn9OKxqTiqdBDKfX0ygxcg64pGj5ZyfF6OmoTSK 0IcqbU09/s5BDVtE8aYEeNWVm87dmBRArxP3JXrwrMrnW9jKwJxLhRuwKFUY9kzEFE ZajglOFWkQqxjnnXGlTDk0G8SUvveo2qbtBZ7FJ0= Subject: FAILED: patch "[PATCH] x86/speculation: Make all RETbleed mitigations 64-bit only" failed to apply to 5.15-stable tree To: ben@decadent.org.uk, bp@suse.de, stable@vger.kernel.org Cc: From: Date: Mon, 25 Jul 2022 11:34:57 +0200 Message-ID: <1658741697107226@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b648ab487f31bc4c38941bc770ea97fe394304bb Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sat, 23 Jul 2022 17:22:47 +0200 Subject: [PATCH] x86/speculation: Make all RETbleed mitigations 64-bit only The mitigations for RETBleed are currently ineffective on x86_32 since entry_32.S does not use the required macros. However, for an x86_32 target, the kconfig symbols for them are still enabled by default and /sys/devices/system/cpu/vulnerabilities/retbleed will wrongly report that mitigations are in place. Make all of these symbols depend on X86_64, and only enable RETHUNK by default on X86_64. Fixes: f43b9876e857 ("x86/retbleed: Add fine grained Kconfig knobs") Signed-off-by: Ben Hutchings Signed-off-by: Borislav Petkov Cc: Link: https://lore.kernel.org/r/YtwSR3NNsWp1ohfV@decadent.org.uk diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index e58798f636d4..1670a3fed263 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2473,7 +2473,7 @@ config RETHUNK bool "Enable return-thunks" depends on RETPOLINE && CC_HAS_RETURN_THUNK select OBJTOOL if HAVE_OBJTOOL - default y + default y if X86_64 help Compile the kernel with the return-thunks compiler option to guard against kernel-to-user data leaks by avoiding return speculation. @@ -2482,21 +2482,21 @@ config RETHUNK config CPU_UNRET_ENTRY bool "Enable UNRET on kernel entry" - depends on CPU_SUP_AMD && RETHUNK + depends on CPU_SUP_AMD && RETHUNK && X86_64 default y help Compile the kernel with support for the retbleed=unret mitigation. config CPU_IBPB_ENTRY bool "Enable IBPB on kernel entry" - depends on CPU_SUP_AMD + depends on CPU_SUP_AMD && X86_64 default y help Compile the kernel with support for the retbleed=ibpb mitigation. config CPU_IBRS_ENTRY bool "Enable IBRS on kernel entry" - depends on CPU_SUP_INTEL + depends on CPU_SUP_INTEL && X86_64 default y help Compile the kernel with support for the spectre_v2=ibrs mitigation.