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 X-Spam-Level: X-Spam-Status: No, score=-8.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 12CEEC47082 for ; Tue, 8 Jun 2021 21:16:11 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CFB2D6044F for ; Tue, 8 Jun 2021 21:16:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CFB2D6044F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Mime-Version:References:In-Reply-To: Message-Id:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=LBFKTugo71cQgq9PDPPAVCLtIfG0BL9UAE7KOQeGGFI=; b=RrcaAFTwL80ksC 4WhmXoUPlrTJECXtsZL1fIeGp1u3y9bP6x331F4Y2IyBGs7WFbGiW+21f1pzgFJzJUu/sDRXDgqoP uIBqU+wNdM2bvDsxZK2tFAvyi3sR31GrgzCybnt+cBD78e4rM/s221Sya0q6WNVkUL2l1UxsYcAGv rwTuoil/fnweTnNAFBEQVAs+dS2nANANHaEkZW0njPgmbS8I6XPVSU4vpPZNS/StCDjL44I7B+n6v 9fv9BhLCOrV8S+FIbEdHC6XjO1QdsxVgJW0aRpLHf2k8MsnL0qGx6UaPDEOA+5dTY7jJczKUEIxlG nyIg0FgvjPpun15k+yMw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lqj3G-00AWVw-2O; Tue, 08 Jun 2021 21:14:22 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1lqj37-00AWTw-WC; Tue, 08 Jun 2021 21:14:18 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 52E3660FD8; Tue, 8 Jun 2021 21:14:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1623186852; bh=G2smJxvAvuJyR2PVlfkCgvduPlzSv6hHhHX7NFNY20I=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=FSXWgxmd8Uuly+8F/DNMxKu28peM0aEDJWzKxZhCGVBW3OFtmBlFiFDRnIaxVwEjp U+bMQ8ZGcX8xc9CsXU0xGdx9cw1evm79PHu5nuqSh5775dEpcL/aIdLs0/8ZpVRs0n pieXRb46jjM8WiXkFPegtAY9/fQA7BshRhnEuDpc= Date: Tue, 8 Jun 2021 14:14:10 -0700 From: Andrew Morton To: Baoquan He Cc: Pingfan Liu , Bhupesh Sharma , Kazuhito Hagio , Dave Young , Boris Petkov , Ingo Molnar , Thomas Gleixner , James Morse , Mark Rutland , Will Deacon , Catalin Marinas , Michael Ellerman , Paul Mackerras , Benjamin Herrenschmidt , Dave Anderson , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] crash_core, vmcoreinfo: Append 'SECTION_SIZE_BITS' to vmcoreinfo Message-Id: <20210608141410.0026a925ba3a609b0dd4e560@linux-foundation.org> In-Reply-To: <20210608142432.GA587883@MiWiFi-R3L-srv> References: <20210608103359.84907-1-kernelfans@gmail.com> <20210608142432.GA587883@MiWiFi-R3L-srv> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210608_141414_089373_9342CC25 X-CRM114-Status: GOOD ( 16.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, 8 Jun 2021 22:24:32 +0800 Baoquan He wrote: > On 06/08/21 at 06:33am, Pingfan Liu wrote: > > As mentioned in kernel commit 1d50e5d0c505 ("crash_core, vmcoreinfo: > > Append 'MAX_PHYSMEM_BITS' to vmcoreinfo"), SECTION_SIZE_BITS in the > > formula: > > #define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS) > > > > Besides SECTIONS_SHIFT, SECTION_SIZE_BITS is also used to calculate > > PAGES_PER_SECTION in makedumpfile just like kernel. > > > > Unfortunately, this arch-dependent macro SECTION_SIZE_BITS changes, e.g. > > recently in kernel commit f0b13ee23241 ("arm64/sparsemem: reduce > > SECTION_SIZE_BITS"). But user space wants a stable interface to get this > > info. Such info is impossible to be deduced from a crashdump vmcore. > > Hence append SECTION_SIZE_BITS to vmcoreinfo. > > ... > > Add the discussion of the original thread in kexec ML for reference: > http://lists.infradead.org/pipermail/kexec/2021-June/022676.html I added a Link: for this. > This looks good to me. > > Acked-by: Baoquan He I'm thinking we should backport this at least to Fixes:f0b13ee23241. But perhaps it's simpler to just backport it as far as possible, so I added a bare cc:stable with no Fixes:. Thoughts? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel