From patchwork Tue Mar 1 08:11:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ammar Faizi X-Patchwork-Id: 547507 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 BEDE0C433FE for ; Tue, 1 Mar 2022 08:11:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230282AbiCAIMf (ORCPT ); Tue, 1 Mar 2022 03:12:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56758 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233166AbiCAIMe (ORCPT ); Tue, 1 Mar 2022 03:12:34 -0500 Received: from gnuweeb.org (gnuweeb.org [51.81.211.47]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39E3883003; Tue, 1 Mar 2022 00:11:54 -0800 (PST) Received: from integral2.. (unknown [182.2.70.248]) by gnuweeb.org (Postfix) with ESMTPSA id B483F7EC80; Tue, 1 Mar 2022 08:11:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gnuweeb.org; s=default; t=1646122313; bh=zdjHxjV5WVf3cpuRmNxzzSq7B8CXjRT0mG4Lpjuog2o=; h=From:To:Cc:Subject:Date:From; b=MfhrwLxxD6kbQ0SCSfBIQCUUYcBnNglFhXQXnhx/zNIuKqnZ8rpvS9rEsrnnw+FY3 2+63aUj+4tLVqiBi/2dVnNroml53rrruClzZjOQq8C3sgSvFd78yqmU3jNm/4t7Ksy dyi4+DiYLpgTO0D+lxna9FaZiWY3HRdpu9MKni9Na1lN3Vy6kSmckbp9ztBihmrgAc NuYlJR243Pg6pdV9TQEW62Lr1qPmT4ROCcaR1JEldcAM8CzanzU3emU2jkd51JE8Dr A+/gLVNsuNmxLnZyNcUkhHc3K45rVnugcvoa8bEomUH95jN+a0TLq18y9RVyAar8Y7 lv15MZzmpjdkA== From: Ammar Faizi To: Borislav Petkov Cc: Dave Hansen , "H. Peter Anvin" , Ingo Molnar , Thomas Gleixner , Tony Luck , linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org, gwml@vger.gnuweeb.org, x86@kernel.org, stable@vger.kernel.org, Alviro Iskandar Setiawan , Ammar Faizi Subject: [PATCH v3 0/2] Two x86 fixes Date: Tue, 1 Mar 2022 15:11:31 +0700 Message-Id: <20220301081133.106875-1-ammarfaizi2@gnuweeb.org> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Hi, Two fixes for x86 arch. ## Changelog v3: - Fold in changes from Alviro, the previous version is still leaking @bank[n]. v2: - Fix wrong copy/paste. ## Summary [PATCH v3 1/2] x86/delay: Fix the wrong asm constraint in `delay_loop()` The asm constraint does not reflect that the asm statement can modify the value of @loops. But the asm statement in delay_loop() does change the @loops. If by any chance the compiler inlines this function, it may clobber random stuff (e.g. local variable, important temporary value in reg, etc.). Fortunately, delay_loop() is only called indirectly (so it can't inline), and then the register it clobbers is %rax (which is by the nature of the calling convention, it's a caller saved register), so it didn't yield any bug. ^ That shouldn't be an excuse for using the wrong constraint anyway. This changes "a" (as an input) to "+a" (as an input and output). [PATCH v3 2/2] x86/mce/amd: Fix memory leak when `threshold_create_bank()` fails. @bp is a local variable, calling mce_threshold_remove_device() when threshold_create_bank() fails will not free the @bp. Note that mce_threshold_remove_device() frees the @bp only if it's already stored in the @threshold_banks per-CPU variable. At that point, the @threshold_banks per-CPU variable is still NULL, so the mce_threshold_remove_device() will just be a no-op and the @bp is leaked. Fix this by storing @bp to @threshold_banks before the loop, so in case we fail, mce_threshold_remove_device() will free the @bp. This bug is introduced by commit 6458de97fc15530b544 ("x86/mce/amd: Straighten CPU hotplug path") [1]. Cc: Borislav Petkov Cc: Dave Hansen Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Tony Luck Signed-off-by: Alviro Iskandar Setiawan Signed-off-by: Ammar Faizi --- Ammar Faizi (2): x86/delay: Fix the wrong asm constraint in `delay_loop()` x86/mce/amd: Fix memory leak when `threshold_create_bank()` fails arch/x86/kernel/cpu/mce/amd.c | 16 ++++++++++------ arch/x86/lib/delay.c | 4 ++-- 2 files changed, 12 insertions(+), 8 deletions(-) base-commit: 7e57714cd0ad2d5bb90e50b5096a0e671dec1ef3