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 8F6E2C433F5 for ; Wed, 30 Mar 2022 20:53:43 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E4BB76B0072; Wed, 30 Mar 2022 16:53:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id DFA6E6B0073; Wed, 30 Mar 2022 16:53:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CE8DA8D0001; Wed, 30 Mar 2022 16:53:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0166.hostedemail.com [216.40.44.166]) by kanga.kvack.org (Postfix) with ESMTP id C06A26B0072 for ; Wed, 30 Mar 2022 16:53:42 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 72BB1182DD9E9 for ; Wed, 30 Mar 2022 20:53:42 +0000 (UTC) X-FDA: 79302253884.16.052C153 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf12.hostedemail.com (Postfix) with ESMTP id 047504000B for ; Wed, 30 Mar 2022 20:53:41 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 38F5961678; Wed, 30 Mar 2022 20:53:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8567FC340EC; Wed, 30 Mar 2022 20:53:39 +0000 (UTC) Date: Wed, 30 Mar 2022 16:53:37 -0400 From: Steven Rostedt To: Zi Yan Cc: Linus Torvalds , LKML , Mel Gorman , David Hildenbrand , Vlastimil Babka , Mike Rapoport , Oscar Salvador , Andrew Morton , Linux-MM Subject: Re: [BUG] Crash on x86_32 for: mm: page_alloc: avoid merging non-fallbackable pageblocks with others Message-ID: <20220330165337.7138810e@gandalf.local.home> In-Reply-To: References: <20220330154208.71aca532@gandalf.local.home> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: k6pdcwimbctw147zpwjrbg8m8tq6xy6a Authentication-Results: imf12.hostedemail.com; dkim=none; spf=pass (imf12.hostedemail.com: domain of "SRS0=X/cO=UJ=goodmis.org=rostedt@kernel.org" designates 139.178.84.217 as permitted sender) smtp.mailfrom="SRS0=X/cO=UJ=goodmis.org=rostedt@kernel.org"; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 047504000B X-HE-Tag: 1648673621-673726 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, 30 Mar 2022 16:29:28 -0400 Zi Yan wrote: > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index bdc8f60ae462..83a90e2973b7 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1108,6 +1108,8 @@ static inline void __free_one_page(struct page *page, > > buddy_pfn = __find_buddy_pfn(pfn, order); > buddy = page + (buddy_pfn - pfn); > + if (!page_is_buddy(page, buddy, order)) > + goto done_merging; > buddy_mt = get_pageblock_migratetype(buddy); > > if (migratetype != buddy_mt > The above did not apply to Linus's tree, nor even the problem commit (before or after), but I found where the code is, and added it manually. It does appear to allow the machine to boot. -- Steve