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 392DBC433FE for ; Wed, 19 Jan 2022 15:56:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355981AbiASP4B (ORCPT ); Wed, 19 Jan 2022 10:56:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37066 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237164AbiASPz7 (ORCPT ); Wed, 19 Jan 2022 10:55:59 -0500 Received: from mail-oo1-xc30.google.com (mail-oo1-xc30.google.com [IPv6:2607:f8b0:4864:20::c30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B36CEC061574; Wed, 19 Jan 2022 07:55:59 -0800 (PST) Received: by mail-oo1-xc30.google.com with SMTP id l7-20020a4a2707000000b002dde197c749so853806oof.10; Wed, 19 Jan 2022 07:55:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:to:cc:references:from:subject:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=aSGUAl3gocAm+DLJ0aQCnbcEeJnsi/wUpekX13IHCuo=; b=fOyNg4qcUt37pe7laWsmJ8fvNB0XmoDH2Mnynw/z/yiAIkeF9QGVcvVKHDh0CATJts zO5iGRvLbyoJTlKkDb0qC2HqFADSFpf2c9tngfm67w5NUC+9WHmTuDLyY9dIx8JI4wcj R6V/jy2GJKkgOyQEtcdR+lbPAtOh+jdCFpVnqTgid5j6cALrz+Fmd3raXSkpA5gqUmRi YFTuf9Cqd09aQyjvX8yccM1BLzP0Q1K+iBxPbBxNraBAlC09a+0+FFxIrVxaKWZ5mFWF X07qRou0GjQ94bld8IDC3F5eFMPKCi3qP3lXFhRlWhwfAAV2Y2/UaHJWBAnmFKo76Oij DpbQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:to:cc:references:from:subject:message-id :date:user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=aSGUAl3gocAm+DLJ0aQCnbcEeJnsi/wUpekX13IHCuo=; b=z3WYPaMZgMQLK7DLVDe7CybDbiqdIy7x7jDkRcDK+lc/KzXtUEsF1SGf8KzJ0batM3 aS43hAAz1BxiY2ZCdm3b3h1cxDNqfbPyCNDO6UG2ksKQFLy8HdXKkrPHstiCXbhgUw6a 5+SzxG8Sk8ugMzGJ/QR7Mnv5y7h1DQ4pqHhNOyUfhsoJztSRggPitpTRxWAtsLxrcbT0 33BGNI5jjRYNoORLBY2+H39C7uGKe3I1LMZUZDLTC6bj2kqx9vefxBV0889LGCnS1e6V rcr7QVnTRJkPPKtVk6bFfxlMDJoYF4J0ZNYyp+5d5LxnOH1Sa0ZFkrgptv2JB7Ks2uMv 43fA== X-Gm-Message-State: AOAM532nYg75ZgtyUZqEfOZ1h2fp0w7CmDjs9PQ/+tLsLAcqjnbC/t1B dG1ZA1RfqPIWPmTZ96dS1Xw= X-Google-Smtp-Source: ABdhPJwVX9iXytkWG/lvP0m/HVAdUHyAlz8jdPDfjrDOPS01ehS+jf00fWaTpgkNwzul7ep+I3Zeng== X-Received: by 2002:a4a:3851:: with SMTP id o17mr22448953oof.6.1642607759105; Wed, 19 Jan 2022 07:55:59 -0800 (PST) Received: from server.roeck-us.net ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id t14sm8853466oth.81.2022.01.19.07.55.56 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 19 Jan 2022 07:55:58 -0800 (PST) Sender: Guenter Roeck To: Linus Torvalds , Naresh Kamboju Cc: Greg Kroah-Hartman , Christian Brauner , NeilBrown , Linux Kernel Mailing List , Andrew Morton , Shuah Khan , patches@kernelci.org, lkft-triage@lists.linaro.org, Pavel Machek , Jon Hunter , Florian Fainelli , stable , Al Viro , Arnd Bergmann References: <20220118160452.384322748@linuxfoundation.org> From: Guenter Roeck Subject: Re: [PATCH 5.16 00/28] 5.16.2-rc1 review Message-ID: <45b72e1b-d98b-ba4e-fc08-ab7b122d69ef@roeck-us.net> Date: Wed, 19 Jan 2022 07:55:55 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/18/22 11:53 PM, Linus Torvalds wrote: > On Wed, Jan 19, 2022 at 9:30 AM Naresh Kamboju > wrote: >> >> Inconsistent kallsyms data > > This tends to be a "odd build environment" problem, and very very > random. Triggered by very particular compiler versions and just some > odd code modement details. > It happens once in a while depending on the compiler version and on how symbols are arranged, and new compiler specific symbols showing up. I had submitted a patch a while ago that kept retrying a few more times before giving up (that was rejected). We carry a patch in ChromeOS kernels which tells us what the offending symbols are in case we see the problem in our builds. > I'd suggest doing a completely clean build and disabling ccache, and > seeing if that makes it go away. > My experience is that once it starts, it will show up randomly and become more and more prevalent over time until almost all builds fail. powerpc seems to be affected a lot by this problem, but we have also seen it on x86. When that happens, someone has to go in and figure out the offending symbol(s) and add it or them to some exception list. Guenter