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 09E1CC433FE for ; Wed, 5 Jan 2022 17:21:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242199AbiAERVx (ORCPT ); Wed, 5 Jan 2022 12:21:53 -0500 Received: from mengyan1223.wang ([89.208.246.23]:53730 "EHLO mengyan1223.wang" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230323AbiAERVw (ORCPT ); Wed, 5 Jan 2022 12:21:52 -0500 Received: from localhost.localdomain (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-384) server-digest SHA384) (Client did not present a certificate) (Authenticated sender: xry111@mengyan1223.wang) by mengyan1223.wang (Postfix) with ESMTPSA id E325B65A9A; Wed, 5 Jan 2022 12:21:47 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mengyan1223.wang; s=mail; t=1641403311; bh=lQqSduRsA0o4a6IM8NvLfUF17x9jJ4pL2pbwCbpBxGk=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=CD8a5zlaG4oMTVKQcjfPEvVw3OAsjNPOenLOzpJp4z7vHcJxn5sgd6xK/Bo85swjr NpvPed3l/CMmy6sdRN/f8SJ9Cs6fGOu1CaSkiJxnzkoQSWRORevjPfwDu776xw3Rti T8YRP2GWWHJoHth74vppw0ZMD+p+CKfWp9qz0PLBc3vKzum3Xqxr6dgK1811DLSBSs VYTneXQhGWcwQyQo7mvD54eOyzq0NwOJsO21UQKc3PFAzl3c+ZbuYR6RJh210V0zfI yPfRrzzpfwdi4YDkGOwsNCmawJsbZ0vZW6czapW3ULBgJhXXJnjuVC+mt365heLm+y +K8EgwolkMWKg== Message-ID: <211edcb700db30c4a6b37db87139e5fa47aeece0.camel@mengyan1223.wang> Subject: Re: [PATCH V5 00/22] arch: Add basic LoongArch support From: Xi Ruoyao To: Huacai Chen Cc: Huacai Chen , Arnd Bergmann , Andy Lutomirski , Thomas Gleixner , Peter Zijlstra , Andrew Morton , David Airlie , Jonathan Corbet , Linus Torvalds , linux-arch , "open list:DOCUMENTATION" , LKML , Xuefeng Li , Yanteng Si , Jiaxun Yang Date: Thu, 06 Jan 2022 01:21:46 +0800 In-Reply-To: <6d0169ca8c9e417308d3b9f96cd0ef446ee36fe7.camel@mengyan1223.wang> References: <20211013063656.3084555-1-chenhuacai@loongson.cn> <722477bcc461238f96c3b038b2e3379ee49efdac.camel@mengyan1223.wang> <587ab54d77af2fb4cdbe0530cdd5e550c3e968db.camel@mengyan1223.wang> <6d0169ca8c9e417308d3b9f96cd0ef446ee36fe7.camel@mengyan1223.wang> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2022-01-05 at 19:51 +0800, Xi Ruoyao wrote: > On Wed, 2022-01-05 at 17:40 +0800, Huacai Chen wrote: > > Hi, Ruoyao, > > > > The problem still exists in 5.16-rc8, can you try to change > > cpu_relax() definition to smp_mb()? It seems can fix the problem. > > Is there any workload which can triggers the panic?  I can't trigger it > by building and testing GCC, or building the kernel anymore. > > And is your "stable" issue the same one I'd encountered?  To me changing > barrier() to smp_mb() may fix some deadlock, but not a panic.  (I'm not > an expert on CPU architecture or kernel programming, so maybe I'm wrong > here.) > > I'll put my 3A5000 machine into a loop building kernel and see if I can > trigger the panic again... I can't reproduce the issue on 5.16-rc8. But I can reproduce it on 5.16-rc5 and the s/barrier/smp_mb/ change fixes the issue. I'm still puzzled: if there some workload which can reproduce the issue more deterministic? -- Xi Ruoyao School of Aerospace Science and Technology, Xidian University