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 BFBA5C0015E for ; Sat, 5 Aug 2023 17:08:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CE9D68D0002; Sat, 5 Aug 2023 13:08:09 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C990F8D0001; Sat, 5 Aug 2023 13:08:09 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B39A58D0002; Sat, 5 Aug 2023 13:08:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 9FBDF8D0001 for ; Sat, 5 Aug 2023 13:08:09 -0400 (EDT) Received: from smtpin29.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 642E8A0385 for ; Sat, 5 Aug 2023 17:08:09 +0000 (UTC) X-FDA: 81090683898.29.2A7AF03 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf23.hostedemail.com (Postfix) with ESMTP id 3CAD214001F for ; Sat, 5 Aug 2023 17:08:04 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b="AmKIfX/0"; dmarc=none; spf=none (imf23.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1691255285; h=from:from: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=uQ9RgvUaYz5ZoHkSz4TftrkTzewOwk1/pabomeJDyDQ=; b=rejdji08YjgmMt+G76bOJVOh8ul3XefUVPYRcEOaAMUkdmdVJ8GnYldXF8gYMegYHPV1GQ /VxeGfY5AIVIpraAGVQuXQq9fEJxFFd88BXri8UWdw+eks4nXtW+gIK6eXKYWPZqvNDgYF ILTwq7g7EN8iYJOcnbcFZKrcpdA4yFA= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b="AmKIfX/0"; dmarc=none; spf=none (imf23.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1691255285; a=rsa-sha256; cv=none; b=uzXABM4Y4s3FRoOKaCrNeuvZHRRGkMgRipS3Z3PGcxIhYS0ikr1CAnPXZaZiwLVAj8cljc 7fRfnVh2TW9NZFnCUK0bNl8YupNpJzj2OWbkHiM9uT9XDC5sMH+BcCcVpwAKmhwb/d2q/t TGBKr3ZbWdZvjm6Y6zcT4HIaVjsEGqw= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=uQ9RgvUaYz5ZoHkSz4TftrkTzewOwk1/pabomeJDyDQ=; b=AmKIfX/0U64+sAeS/5/upk0HBy lT9wElStLEcXTuLFF5qomt3n0sjH+6cAw0SqLTFl78kCR+jM/gZTMZbP/faaFX1cIkibWILBZzT1f eccJG/c5EuNSn5/3/8KulVBGEdLXSTwpk4uVg2Lirr5IDzoi6w6WH8j0HHoyNSNrgAVWKtgigjJk8 A3dEZ5XWmkgtnexBs1J3Muaw9U+gJNb4cBxEAFTm7R0Uqy8vDLqduNT2DHfxWItpHolwnKPre5y5v dRHgsdEFeo37W1+0/TIhXxACWMURHwANbIPD1pCfAn7zsJv3G58u8GbDChorewlSfAneXOGlqdGzd JymtXjyg==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1qSKk5-00H5kj-2R; Sat, 05 Aug 2023 17:07:05 +0000 Date: Sat, 5 Aug 2023 18:07:05 +0100 From: Matthew Wilcox To: Yongqin Liu Cc: Hugh Dickins , Andrew Morton , Mike Kravetz , Mike Rapoport , "Kirill A. Shutemov" , David Hildenbrand , Suren Baghdasaryan , Qi Zheng , Yang Shi , Mel Gorman , Peter Xu , Peter Zijlstra , Will Deacon , Yu Zhao , Alistair Popple , Ralph Campbell , Ira Weiny , Steven Price , SeongJae Park , Lorenzo Stoakes , Huang Ying , Naoya Horiguchi , Christophe Leroy , Zack Rusin , Jason Gunthorpe , Axel Rasmussen , Anshuman Khandual , Pasha Tatashin , Miaohe Lin , Minchan Kim , Christoph Hellwig , Song Liu , Thomas Hellstrom , Ryan Roberts , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2 04/32] mm/pgtable: allow pte_offset_map[_lock]() to fail Message-ID: References: <2929bfd-9893-a374-e463-4c3127ff9b9d@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 3CAD214001F X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: 673obyan1s1p8kgphqgwxyzjq41468e5 X-HE-Tag: 1691255284-43382 X-HE-Meta: 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 Q6WVVrP+ yUyoR/AIF20wzzWtkh7xftNPNTrZDTxflFgBzeVXH6qUXYrkqZutkQblMnIfcGX1Xcefv9aTULCbr+tQU2wuIWwb1RASd7LurDgwNq8+3mpWJjfj3uoQfNTYQx7q+j6Rmh8CCkFP5HGYFMP5IoawjH8HKn+rF0o4oWRwMeJGXAYvn/DKSVaGEExn0oQc6cgbY/uAwEFP1cRQfakUAsaeE0Ghb0XeQbbylnbJUKolPD0aAW5eWBgBJYaWQaGNB1sJpw9pTqJM5fRG6rrU= 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 Sun, Aug 06, 2023 at 12:06:28AM +0800, Yongqin Liu wrote: > On Sat, 29 Jul 2023 at 00:58, Hugh Dickins wrote: > > > > On Fri, 28 Jul 2023, Matthew Wilcox wrote: > > > On Fri, Jul 28, 2023 at 09:53:29PM +0800, Yongqin Liu wrote: > > > > Hi, Hugh > > > > > > > > It seems this change makes pte_offset_map_lock not possible to be > > > > called in out of tree modules, > > > > otherwise it will report error like this: > > > > ERROR: modpost: "__pte_offset_map_lock" > > > > [../omap-modules/android-mainline/pvr/pvrsrvkm.ko] undefined! > > > > > > > > Not sure if you have any idea about it, and any suggestions on how to > > > > resolve it? > > > > > > Please explain why this module needs to map page tables > > > > +1 > Sorry, I am not able to give any explanation here, > I am not familiar with the pvrsrvkm source, I just use it to have one > working AOSP build. > > here is the source file where pte_offset_map_lock is called, > https://android-git.linaro.org/kernel/omap-modules.git/tree/pvr/services4/srvkm/env/linux/osfunc.c?h=android-mainline#n3508 > in case you could know something with a quick look. Isn't this just get_user_pages()?