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 57439C433F5 for ; Tue, 31 May 2022 08:56:43 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AAF8F6B0075; Tue, 31 May 2022 04:56:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A5F5D6B0078; Tue, 31 May 2022 04:56:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 925986B007B; Tue, 31 May 2022 04:56:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 507AC6B0075 for ; Tue, 31 May 2022 04:56:42 -0400 (EDT) Received: from smtpin14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 2099C340FC for ; Tue, 31 May 2022 08:56:41 +0000 (UTC) X-FDA: 79525432644.14.ABF2A39 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by imf14.hostedemail.com (Postfix) with ESMTP id 26A5D10004E for ; Tue, 31 May 2022 08:56:33 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 86D2C1F975; Tue, 31 May 2022 08:56:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1653987394; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=9Holi8WFcRRs2SBumcgZOpppBJDzx0jCIMI4rlCkjmY=; b=oY0WVqHGEUGdSpZh8ADVsO97wS/tQ1QCcyzbZEedjjQBJrQ1kE+xvyqQciIgCeSl/Tvf2e R7KXu9YZNaHIcF/w/iLIR5K6prHInRH1xT2/KnIUSpIb3RIdobCQT51JVrSAgCw3SrBa2X 6Q6N1BITChk+32ujBPFPDwbGM33jxbU= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1653987394; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=9Holi8WFcRRs2SBumcgZOpppBJDzx0jCIMI4rlCkjmY=; b=SP3kEsYuGUsw8sbI7sgdD++c7pUR9sMzWN2FQ/cUS6Oj+2E6nI5YSaZaFCgA4h93RPEDc/ Hy4y+YO8bQGbH4AQ== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 935C513AA2; Tue, 31 May 2022 08:56:33 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id RuIyIUHYlWLOfwAAMHmgww (envelope-from ); Tue, 31 May 2022 08:56:33 +0000 Date: Tue, 31 May 2022 10:56:31 +0200 From: Oscar Salvador To: Zi Yan Cc: Andrew Morton , David Hildenbrand , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Qian Cai , Vlastimil Babka , Mel Gorman , Eric Ren , Mike Rapoport , Christophe Leroy , Anshuman Khandual Subject: Re: [PATCH] mm: page_isolation: use compound_nr() correctly in isolate_single_pageblock() Message-ID: References: <20220531024450.2498431-1-zi.yan@sent.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220531024450.2498431-1-zi.yan@sent.com> X-Rspamd-Queue-Id: 26A5D10004E X-Stat-Signature: jbouno5z7u93eixxtxud46f1bndwt1j8 Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=oY0WVqHG; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=SP3kEsYu; dmarc=pass (policy=none) header.from=suse.de; spf=pass (imf14.hostedemail.com: domain of osalvador@suse.de designates 195.135.220.29 as permitted sender) smtp.mailfrom=osalvador@suse.de X-Rspam-User: X-Rspamd-Server: rspam11 X-HE-Tag: 1653987393-346844 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 Mon, May 30, 2022 at 10:44:50PM -0400, Zi Yan wrote: > From: Zi Yan > > When compound_nr(page) was used, page was not guaranteed to be the head > of the compound page and it could cause an infinite loop. Fix it by calling > it on the head page. > > Fixes: b2c9e2fbba32 ("mm: make alloc_contig_range work at pageblock granularity") > Reported-by: Anshuman Khandual > Link: https://lore.kernel.org/linux-mm/20220530115027.123341-1-anshuman.khandual@arm.com/ > Signed-off-by: Zi Yan Reviewed-by: Oscar Salvador > --- > mm/page_isolation.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/page_isolation.c b/mm/page_isolation.c > index 6021f8444b5a..d200d41ad0d3 100644 > --- a/mm/page_isolation.c > +++ b/mm/page_isolation.c > @@ -385,9 +385,9 @@ static int isolate_single_pageblock(unsigned long boundary_pfn, int flags, > * above do the rest. If migration is not possible, just fail. > */ > if (PageCompound(page)) { > - unsigned long nr_pages = compound_nr(page); > struct page *head = compound_head(page); > unsigned long head_pfn = page_to_pfn(head); > + unsigned long nr_pages = compound_nr(head); > > if (head_pfn + nr_pages <= boundary_pfn) { > pfn = head_pfn + nr_pages; > -- > 2.35.1 > -- Oscar Salvador SUSE Labs