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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 823EEC433B4 for ; Thu, 22 Apr 2021 01:07:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0C54F61424 for ; Thu, 22 Apr 2021 01:07:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C54F61424 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 69FC16B006C; Wed, 21 Apr 2021 21:07:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 675906B006E; Wed, 21 Apr 2021 21:07:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 540DE6B0070; Wed, 21 Apr 2021 21:07:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0004.hostedemail.com [216.40.44.4]) by kanga.kvack.org (Postfix) with ESMTP id 379836B006C for ; Wed, 21 Apr 2021 21:07:31 -0400 (EDT) Received: from smtpin31.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id F2C22940F for ; Thu, 22 Apr 2021 01:07:30 +0000 (UTC) X-FDA: 78058215060.31.6B1AF68 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf21.hostedemail.com (Postfix) with ESMTP id 7B835E000105 for ; Thu, 22 Apr 2021 01:07:27 +0000 (UTC) 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=VRNWJ7dwbgZwlJyhYfwGgpaJzbScF/7s6fzKyBnonnk=; b=WtR6qF+FGYDnWHNpr57Amm2uZk ZgQuQYsiGxtuRwxgwalTqgLJID5Xudtgan2AHAeyR9GnxsHku9D0Au88l9Yp1FylXEuang+V9AgNX W3Ut/B+QNa7FXpswe5iQmJQD9vUJjTRdu50fGl/hVEJe0wwvYUD2gfscP4OrpgURDThZCrZcqHGMv kSuC25KwvxN7vHm3opYhbdp+aUt+SXdxC01mzy3FZ4ZtUtw0V2EYvk6lib5d+5gUZU57+zncdBD+M gEZpNUh8Wxziorc+1auBCeqSuHK9fWV/5G6Rc5c2EQxU7fpo67nO6zwkUGXMLMnTI84qzCHt7DsBy 99LU24HA==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lZNna-00HGPa-Uh; Thu, 22 Apr 2021 01:06:35 +0000 Date: Thu, 22 Apr 2021 02:06:30 +0100 From: Matthew Wilcox To: Hugh Dickins Cc: Andrew Morton , William Kucharski , Christoph Hellwig , Jan Kara , Dave Chinner , Johannes Weiner , "Kirill A. Shutemov" , Yang Shi , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 1/2] mm/filemap: fix find_lock_entries hang on 32-bit THP Message-ID: <20210422010630.GK3596236@casper.infradead.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 7B835E000105 X-Stat-Signature: ht46fojftsq8fgaspwp6y5h9krjoiydk X-Rspamd-Server: rspam02 Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf21; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619053647-217791 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 Wed, Apr 21, 2021 at 05:37:33PM -0700, Hugh Dickins wrote: > - if (!xa_is_value(page) && PageTransHuge(page)) > - xas_set(&xas, page->index + thp_nr_pages(page)); > + if (!xa_is_value(page) && PageTransHuge(page)) { > + unsigned int nr_pages = thp_nr_pages(page); > + > + /* Final THP may cross MAX_LFS_FILESIZE on 32-bit */ > + xas_set(&xas, page->index + nr_pages); > + if (xas.xa_index < nr_pages) > + break; > + } Aargh. We really need to get the multi-index support in; this works perfectly when the xas_set() hack isn't needed any more.