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 1E16AC77B73 for ; Mon, 22 May 2023 11:24:03 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7E810900004; Mon, 22 May 2023 07:24:02 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 77150900002; Mon, 22 May 2023 07:24:02 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 612C9900004; Mon, 22 May 2023 07:24:02 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 4D0F4900002 for ; Mon, 22 May 2023 07:24:02 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 1C2821A0D94 for ; Mon, 22 May 2023 11:24:02 +0000 (UTC) X-FDA: 80817656724.01.EE7BCBD Received: from out-11.mta0.migadu.com (out-11.mta0.migadu.com [91.218.175.11]) by imf08.hostedemail.com (Postfix) with ESMTP id 40E74160017 for ; Mon, 22 May 2023 11:23:59 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=wYAfpowm; spf=pass (imf08.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.11 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1684754640; a=rsa-sha256; cv=none; b=709dJZLz9qcn27HhiMv046nBxJI/clkrMhsSlxFyEbU+GnRJJvefWBcODOTm0y7Qg7TSzG 4eGMpyihF7ltuQgrM92RF35VG0QtMYoMsjss577EgI7k4mJY+SaxAVoJk14yS9nIQv+qbL kyJ9Uu72bXpTFgtSZMTE1ekhIiupYho= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=wYAfpowm; spf=pass (imf08.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.11 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1684754640; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=JtdmhQrWCFQED7VOg3cXi10j0gVoa/bMjFtzex/rw04=; b=nIet4DfOxUWUBLIo8/CD5pt3SlXrCkEVawdBvJNnn+lUcvf3JlU+N3pls/AQH9/uqqjOAH /a4C9f7nM12NYf1/s/TVGgXEj1VOxU4bo/8h3wxtCwIejRtu9QyZ/tQSm4e9JayWAtN5PU C5j1xuIVvo4sgip2672EwsSqvh1Khlw= Message-ID: <8f6057b5-362b-a0f6-2f2f-579debe48fce@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1684754637; h=from:from: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JtdmhQrWCFQED7VOg3cXi10j0gVoa/bMjFtzex/rw04=; b=wYAfpowmOB5btaCjRmN8Sbm4SWX9btJYILcEd+yKi4rcVWdQqHQKAsOgkCwGNwoRxDBGu3 JmI6XP14fHq4euszyA6RqP6axEylSWCsRjucnhVhe/Ev5CnEsc3vtEHsxvoBX/Iv5bPzT1 gdJQ8jKnE3czkHPnEU5nFLolhY8qCvI= Date: Mon, 22 May 2023 19:23:41 +0800 MIME-Version: 1.0 Subject: Re: [PATCH 05/31] mm/filemap: allow pte_offset_map_lock() to fail Content-Language: en-US To: Hugh Dickins , Andrew Morton Cc: Mike Kravetz , Mike Rapoport , "Kirill A. Shutemov" , Matthew Wilcox , 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 , Naoya Horiguchi , Christophe Leroy , Zack Rusin , Jason Gunthorpe , Axel Rasmussen , Anshuman Khandual , Pasha Tatashin , Miaohe Lin , Minchan Kim , Christoph Hellwig , Song Liu , Thomas Hellstrom , linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <68a97fbe-5c1e-7ac6-72c-7b9c6290b370@google.com> <3e6d4f8-9f4d-fa7e-304e-1494dddd45b@google.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Qi Zheng In-Reply-To: <3e6d4f8-9f4d-fa7e-304e-1494dddd45b@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 40E74160017 X-Stat-Signature: rtwetzjkbp7qd5bex1e183tgcmdjy4nr X-Rspam-User: X-HE-Tag: 1684754639-596258 X-HE-Meta: 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 8QG5gVbp KKkuEosoEbESVCqswl4FQPpbEQdunImBEvbBZvg/WQ1IdcRAxaT9C7mYq9Gk5NuzsWW1GZSKgYTWW4phDbowuqqjfiFxpsUpNw66qN0lgmDnEcuh/TdrzxbA3UOwNGnSoLYW7X5Z0+lvIUdFoxC9Cs4MHUfwEU61ZAN77 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 2023/5/22 12:54, Hugh Dickins wrote: > filemap_map_pages() allow pte_offset_map_lock() to fail; and remove the > pmd_devmap_trans_unstable() check from filemap_map_pmd(), which can safely > return to filemap_map_pages() and let pte_offset_map_lock() discover that. > > Signed-off-by: Hugh Dickins > --- > mm/filemap.c | 12 +++++------- > 1 file changed, 5 insertions(+), 7 deletions(-) > > diff --git a/mm/filemap.c b/mm/filemap.c > index 28b42ee848a4..9e129ad43e0d 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -3408,13 +3408,6 @@ static bool filemap_map_pmd(struct vm_fault *vmf, struct folio *folio, > if (pmd_none(*vmf->pmd)) > pmd_install(mm, vmf->pmd, &vmf->prealloc_pte); > > - /* See comment in handle_pte_fault() */ > - if (pmd_devmap_trans_unstable(vmf->pmd)) { > - folio_unlock(folio); > - folio_put(folio); > - return true; > - } > - > return false; > } > > @@ -3501,6 +3494,11 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf, > > addr = vma->vm_start + ((start_pgoff - vma->vm_pgoff) << PAGE_SHIFT); > vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, addr, &vmf->ptl); > + if (!vmf->pte) { > + folio_unlock(folio); > + folio_put(folio); Missing: ret = VM_FAULT_NOPAGE; ? > + goto out; > + } > do { > again: > page = folio_file_page(folio, xas.xa_index); -- Thanks, Qi