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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 143F5C433FE for ; Fri, 19 Nov 2021 10:23:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F00A561B6F for ; Fri, 19 Nov 2021 10:23:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234163AbhKSK03 (ORCPT ); Fri, 19 Nov 2021 05:26:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59572 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231321AbhKSK02 (ORCPT ); Fri, 19 Nov 2021 05:26:28 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C47ABC061574; Fri, 19 Nov 2021 02:23:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=gvdXTg/W2n3kKbuv3dIGKinzbO87/pI65V1In1bjrsM=; b=KdaE+z6SbZ935E8lO4NM5utHGv UsEYEvPWBYYvqGkj+Q3LxJTAfoxrH5w4Rxn0XwaQhkxKtLVlFh8ptyxG+ZflDJTyHjGf/1pRhEdUL BrN0uwUEI5YUsVjHSN7ZtWWF/hMTfnLclgMXlTKZLH63iefadLKm4eZbnU3DgM+sV7rFfZOWXnX4V W6IAFdffjS+ffsXJpbiid/jpm78LVb+2facCvmTn9rHX3SjuDlo/elkNFLp6mu5dymTv5Zjs0yRNc iuoXWyrcpnycu1wiUDa7RvgM1lG36MQ+eReEgJZy3MfzwQaPgduLtM68jsoq1BliaKr/XBtXRqmNw dpvBf58g==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mo12h-00GsQM-4O; Fri, 19 Nov 2021 10:22:52 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 2415930001B; Fri, 19 Nov 2021 11:22:49 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id D724C30AF36F8; Fri, 19 Nov 2021 11:22:49 +0100 (CET) Date: Fri, 19 Nov 2021 11:22:49 +0100 From: Peter Zijlstra To: Qi Zheng Cc: Josh Poimboeuf , Linus Torvalds , Holger Hoffst??tte , Kees Cook , Thomas Gleixner , Justin Forbes , Greg Kroah-Hartman , Linux Kernel Mailing List , Andrew Morton , Guenter Roeck , Shuah Khan , patches@kernelci.org, lkft-triage@lists.linaro.org, Pavel Machek , Jon Hunter , Florian Fainelli , stable Subject: Re: [PATCH] x86: Pin task-stack in __get_wchan() Message-ID: References: <55c7b316-e03d-9e91-d74c-fea63c469b3b@applied-asynchrony.com> <20211118080627.GH174703@worktop.programming.kicks-ass.net> <20211118081852.GM174730@worktop.programming.kicks-ass.net> <20211119020427.2y5esq2czquwmvwc@treble> <759cd319-990f-af23-2f1c-aba55d0768b8@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <759cd319-990f-af23-2f1c-aba55d0768b8@bytedance.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 19, 2021 at 06:02:50PM +0800, Qi Zheng wrote: > This implementation is very similar to stack_trace_save_tsk(), maybe we > can just move stack_trace_save_tsk() out of CONFIG_STACKTRACE and reuse > it. No, we want to move away from the stack_trace_*() API because it has very unclear semantics and various arch implementations differ in details. There's a patch that untangles arch_stack_walk*() from CONFIG_STACKTRACE and we can eventually use that.