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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4FF4EC77B73 for ; Tue, 30 May 2023 19:41:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B36DA280002; Tue, 30 May 2023 15:41:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A96F0280001; Tue, 30 May 2023 15:41:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9380B280002; Tue, 30 May 2023 15:41:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 8158D280001 for ; Tue, 30 May 2023 15:41:58 -0400 (EDT) Received: from smtpin21.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 3C4C040354 for ; Tue, 30 May 2023 19:41:58 +0000 (UTC) X-FDA: 80847941916.21.6A0C0DF Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf23.hostedemail.com (Postfix) with ESMTP id 053D7140004 for ; Tue, 30 May 2023 19:41:55 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=h83GzI9G; dmarc=fail reason="No valid SPF, DKIM not aligned (relaxed)" header.from=kernel.org (policy=none); spf=none (imf23.hostedemail.com: domain of mcgrof@infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=mcgrof@infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1685475716; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=JADWF5FGfjqal0Tm4srMFuXcLVsdz79srAuWZWBhE0U=; b=X/eZDPFtGvcoPFDLlRytIcZTdN44xbm2VORNv6ol+WBijWQrOtbhnu7tK4v1C6beWJsZ7e 1S10QbiDtstzg4kdbaYjaR2EQ57HmJF7APz4t6W9Y1EGdEs04kePpi2FzHJRF+8S2ULO+J uOVqRYodQaCPz5wwhSVurKDU6ARHF8A= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=h83GzI9G; dmarc=fail reason="No valid SPF, DKIM not aligned (relaxed)" header.from=kernel.org (policy=none); spf=none (imf23.hostedemail.com: domain of mcgrof@infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=mcgrof@infradead.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1685475716; a=rsa-sha256; cv=none; b=CwlF5PHNrcV/LuEBrgU1uKawKAsAWORGbowXlGAJ1s1AspA1sATCuk/+Vbouh2B27LdV7Q k50TE3TGmEhvCgqavb1OUjklTv5pD0JRjrUdDG09MvivmOSRx7Zb1ms5OQcuvcSVJVAEU1 8VAL3pIA+K22XfzZ56y92i7nZWYaRSU= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=JADWF5FGfjqal0Tm4srMFuXcLVsdz79srAuWZWBhE0U=; b=h83GzI9GcktWKcxm3mM6r0dFZw gDFov6i/D/ln27TGWCDBsfM8Dp2YSXIPS/PadQ/vuOP1h3KfOXRt/Ai8fqtSLwMPPA12Cqi9fsxx1 busls/x8Bbmq5as1k5M4iPcu+jv5Y4OzfZeFCee+0guhE8+nmfE57I6/H7B7Ihh6piFFztXsoWYjP OYAhAjIj5Zrcp5vuE6HXHhK6/EWyS8a9n0RzpJbz+hN84xLsxNNYkNlVBLucSrghgbLJaaYT0asy9 fMykJWPxnNC1FQbewSoj16im5rO8ZVWciD6VuY92UqYF/2BExw7xImmCHnXCRQD1CvyE6kA4zoUJp 3FXLT1pw==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.96 #2 (Red Hat Linux)) id 1q45Dk-00F0Eb-2F; Tue, 30 May 2023 19:41:28 +0000 Date: Tue, 30 May 2023 12:41:28 -0700 From: Luis Chamberlain To: Lucas De Marchi Cc: Linus Torvalds , Johan Hovold , Petr Pavlu , gregkh@linuxfoundation.org, rafael@kernel.org, song@kernel.org, lucas.de.marchi@gmail.com, christophe.leroy@csgroup.eu, peterz@infradead.org, rppt@kernel.org, dave@stgolabs.net, willy@infradead.org, vbabka@suse.cz, mhocko@suse.com, dave.hansen@linux.intel.com, colin.i.king@gmail.com, jim.cromie@gmail.com, catalin.marinas@arm.com, jbaron@akamai.com, rick.p.edgecombe@intel.com, yujie.liu@intel.com, david@redhat.com, tglx@linutronix.de, hch@lst.de, patches@lists.linux.dev, linux-modules@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, pmladek@suse.com, prarit@redhat.com, lennart@poettering.net Subject: Re: [PATCH 2/2] module: add support to avoid duplicates early on load Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 053D7140004 X-Stat-Signature: 9r4h41k19n3ysykyy4mj1yu5ozobtgsw X-Rspam-User: X-HE-Tag: 1685475715-795232 X-HE-Meta: U2FsdGVkX1+UxwxmdbaremJ9RV2qniyIgoQJvJ16lgnTxGQwBJe6/P70WZBbgc7OeGQfILwN03DHQNo+Bgais7m73iT6LBRJGCfic6DeX38MKh5PgsQX0nNjsmQWWgwCGWDy0QgcdofJWV8D+/PgYeI8FLMTAFw900TD4qnVPZf1gMnj83sPyUKL7RK64Usk8Ji2+uk1TZ9tH26vaUcNZ2vKDEMgKkS+oU5t48gCaWP9fr3d7t3RqwRIGzFqtOhvRuD/psUxkzCOplmNnqraKxou8Zt5w10IP8Yxnf5iGJtE98L+jx2ChUlWSvaRMn12qpnFzGWXShLmyGFUWILwWNeFvTW4lgFIiHViXx0y3evFKPGl2D1vhW667ShggPGDTfo4yU75StPHgaJIFqGmsmluqOXWso4pKWNpLsRd5efuzXln7hmLxvBd7b7FSz4Hpk7jQXnqH/pv6KR2KlC7TKfCmOyEoHuzJlNZPXtf7qXMDS9OdTDnVLZARSORK8sQTz02MaTAiZdfgCleDBLhjon/mQ7YgkWJjHK731DDwkuIn+TPEVjYUTQjy2qrymPuPehVPjl+jeDAaIwp99d2Z1P03lzBblOYYi7KjAa31XuapcZznERCDTn6tGRV34EwdypLAy7HAJO4N2jsL2049Ovpdyjpv1BTWca7EccbxR8qeXVLCQLmQl/zyjAn96XTjSRYtpBos8R69+g+eE3tqkBywN1eoxkwll99Q4w2+UfsbXFvFD/T1YOtBpLSmgLBGWW96MaP842F+Lm3DlhMlEstSIZxn2tpcmW1EJfZ8nOHPJECA3jE1AeviUJy5963gJmJJYtN0RH/8nUhrlz+QCX2rOz8P6U8p7701k3/1Az2xOJp6fzp448NrNyLS9kQVwfhYfkxtEikDdbnMu1+RQPm40bzetHWg1jNnZn+OOSqFe5la7TiM1FxIYutIfkjsIoZPPCK5wr1Dnm1zqV oX3t3GFh MLYE7of/t48sHyMPYKHNtPFwB+VR8ovAuh8oy+u10zLWcMl+esbeHUujskf3spQfX7pw3PhBq7oOIP5BvrcENJY1VUahVgVa4ZC27cWWOwq660FG4FjSNzFgKa3viSI7T8FrGxYWhjS7IP3xYc1kt0psuuC/H+LMS44JglLoL4gbGdGDboPuksTTe/FLcMgJdOO3o5ME/7HJ48U5uYZBWI64v2TZW1zOfafhD60UwUeIFWEZ54swA0FXT1/Bv8Y144sZHOt0KCxv9cdLLIRPLYPy3YNbx6HNNmmeCNe0N9q1u22VryvnLXLT2NMhjkmKBcEfiSlWDQzWLEESWX+oPBKXfjng7Pq0Envj5NeEwdGKLQ0hc9MlMjzmX3VmrI6Vges2+ X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, May 30, 2023 at 10:16:22AM -0700, Lucas De Marchi wrote: > On Tue, May 30, 2023 at 09:22:14AM -0700, Luis Chamberlain wrote: > > Lucas, any thoughts from modules kmod userspace perspective into > > supporting anyone likely issuing concurrent modules requests with > > differing arguments? > > Changing module params like that without first explicitly removing the > module was never supported by kmod or module-init-tools (I'm not digging > the history before 2.6 kernel) That's good enough. > During boot, note there is already a shortcut > if we have the sysfs node already in the "live" state or if the module is > built-in. In that case we will return success or -EEXIST (if the > KMOD_PROBE_IGNORE_LOADED flag was passed). Linus' code would make duplicates wait and share the same return value, ie, no new odd error code is returned. Or are you suggesting -EEXIST should be returned to duplicates if the module succeeded to load instead of 0 ? > The only scenario I can think of during boot in which the module params > could change would be when a buggy initrd is created, i.e. > /etc/modprobed.d/*.conf is in the rootfs but absent from initrd. This helps thanks. > So returning the same error code seems good to me. OK thanks! So just to confirm, it seems fine to return the same error code if duplicates wait, or do you prefer for some reason for there to be an exception and return -EEXIST if the module did succeed in the duplicate case? Luis