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 15706C433F5 for ; Mon, 24 Jan 2022 14:49:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238282AbiAXOtZ (ORCPT ); Mon, 24 Jan 2022 09:49:25 -0500 Received: from fanzine2.igalia.com ([213.97.179.56]:39768 "EHLO fanzine2.igalia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238288AbiAXOtW (ORCPT ); Mon, 24 Jan 2022 09:49:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=uqVI2/Ws/hkfMRXL2wXcv67mAYHEWv6EvXIqlX8je3w=; b=TYHxSTbJB1eaqzyxRRdVvUbh2s TFdCcwzmqxcgS5bRtO1I5FWMw5DN35sNUDb6r6+WI+8hr4Jcp6/YjhMkrrp/Q9rknQi0x2/Vh5fGG 0JRIK278kWepmL6bMs1bxf0sP4MeBKHLdldnehPLqCpPW/yeftviI+6QfACb/YWJFLkXxWYT3suIO zCmy38Uagm3RkcIVJTOeNlxWxRAQA/wWFfSxDLY7cz2nzi2Y/9bnveuo7cu3v7bkBtFlzxITF5yYS giB9T69DYJj1pPwKrWwig1tMrVbCKyAvVdkpc07r8avXCpKJO0jpGVz2mlu9sFa3ypuypea4Mt3sI OlAxEHgg==; Received: from 200-207-58-141.dsl.telesp.net.br ([200.207.58.141] helo=[192.168.1.60]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_128_GCM:128) (Exim) id 1nC0eW-0002Du-A5; Mon, 24 Jan 2022 15:49:04 +0100 Message-ID: Date: Mon, 24 Jan 2022 11:48:44 -0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH V4] notifier/panic: Introduce panic_notifier_filter Content-Language: en-US To: Baoquan He , Masami Hiramatsu , Petr Mladek Cc: HATAYAMA Daisuke , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, dyoung@redhat.com, linux-doc@vger.kernel.org, vgoyal@redhat.com, stern@rowland.harvard.edu, akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com, corbet@lwn.net, halves@canonical.com, kernel@gpiccoli.net, Will Deacon , Kees Cook , Steven Rostedt , Hidehiro Kawai , Vitaly Kuznetsov , John Ogness , "Paul E. McKenney" , Peter Zijlstra , Juergen Gross , mikelley@microsoft.com References: <20220108153451.195121-1-gpiccoli@igalia.com> <20220122105514.GA18258@MiWiFi-R3L-srv> <20220123220711.44f1484c9b510eea8cda9c47@kernel.org> <20220124135902.GB8305@MiWiFi-R3L-srv> From: "Guilherme G. Piccoli" In-Reply-To: <20220124135902.GB8305@MiWiFi-R3L-srv> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 24/01/2022 10:59, Baoquan He wrote: > [...] > About pre_dump, if the dump is crash dump, hope those pre_dump notifiers > will be executed under conditional check, e.g only if 'crash_kexec_post_notifiers' > is specified in kernel cmdline. Hi Baoquan, based on Petr's suggestion, I think pre_dump would be responsible for really *non-intrusive/non-risky* tasks and should be always executed in the panic path (before kdump), regardless of "crash_kexec_post_notifiers". The idea is that the majority of the notifiers would be executed in the post_dump portion, and for that, we have the "crash_kexec_post_notifiers" conditional. I also suggest we have blacklist options (based on function names) for both notifiers, in order to make kdump issues debug easier. Do you agree with that? Feel free to comment with suggestions! Cheers, Guilherme