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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham 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 CB479C433C1 for ; Tue, 30 Mar 2021 18:12:01 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3B152619D1 for ; Tue, 30 Mar 2021 18:12:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3B152619D1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gentoo.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6D2966B0080; Tue, 30 Mar 2021 14:12:00 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6A9616B0081; Tue, 30 Mar 2021 14:12:00 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5C26D6B0082; Tue, 30 Mar 2021 14:12:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0151.hostedemail.com [216.40.44.151]) by kanga.kvack.org (Postfix) with ESMTP id 441B56B0080 for ; Tue, 30 Mar 2021 14:12:00 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id DD6C46C3C for ; Tue, 30 Mar 2021 18:11:59 +0000 (UTC) X-FDA: 77977334358.20.0A158A4 Received: from smtp.gentoo.org (smtp.gentoo.org [140.211.166.183]) by imf18.hostedemail.com (Postfix) with ESMTP id D4D5C200024E for ; Tue, 30 Mar 2021 18:11:58 +0000 (UTC) Date: Tue, 30 Mar 2021 19:11:49 +0100 From: Sergei Trofimovich To: Vlastimil Babka Cc: Andrey Konovalov , Andrew Morton , Alexander Potapenko , Marco Elver , Dmitry Vyukov , Andrey Ryabinin , Andrey Konovalov , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH mm v2] mm, kasan: fix for "integrate page_alloc init with HW_TAGS" Message-ID: <20210330191149.68d93145@sf> In-Reply-To: <404ad944-ab46-cffb-5fbb-3dd7ae25caaa@suse.cz> References: <65b6028dea2e9a6e8e2cb779b5115c09457363fc.1617122211.git.andreyknvl@google.com> <404ad944-ab46-cffb-5fbb-3dd7ae25caaa@suse.cz> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: D4D5C200024E X-Stat-Signature: jn8ipztupa6fsn87wxm35az1zxhzz4tu Received-SPF: none (gentoo.org>: No applicable sender policy available) receiver=imf18; identity=mailfrom; envelope-from=""; helo=smtp.gentoo.org; client-ip=140.211.166.183 X-HE-DKIM-Result: none/none X-HE-Tag: 1617127918-158591 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 Tue, 30 Mar 2021 18:44:09 +0200 Vlastimil Babka wrote: > On 3/30/21 6:37 PM, Andrey Konovalov wrote: > > My commit "integrate page_alloc init with HW_TAGS" changed the order of > > kernel_unpoison_pages() and kernel_init_free_pages() calls. This leads > > to complaints from the page unpoisoning code, as the poison pattern gets > > overwritten for __GFP_ZERO allocations. > > > > Fix by restoring the initial order. Also add a warning comment. > > > > Reported-by: Vlastimil Babka > > Reported-by: Sergei Trofimovich > > Signed-off-by: Andrey Konovalov > > Tested that the bug indeed occurs in -next and is fixed by this. Thanks. Reviewed-by: Sergei Trofimovich > > --- > > mm/page_alloc.c | 8 +++++++- > > 1 file changed, 7 insertions(+), 1 deletion(-) > > > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > > index 033bd92e8398..d2c020563c0b 100644 > > --- a/mm/page_alloc.c > > +++ b/mm/page_alloc.c > > @@ -2328,6 +2328,13 @@ inline void post_alloc_hook(struct page *page, unsigned int order, > > arch_alloc_page(page, order); > > debug_pagealloc_map_pages(page, 1 << order); > > > > + /* > > + * Page unpoisoning must happen before memory initialization. > > + * Otherwise, the poison pattern will be overwritten for __GFP_ZERO > > + * allocations and the page unpoisoning code will complain. > > + */ > > + kernel_unpoison_pages(page, 1 << order); > > + > > /* > > * As memory initialization might be integrated into KASAN, > > * kasan_alloc_pages and kernel_init_free_pages must be > > @@ -2338,7 +2345,6 @@ inline void post_alloc_hook(struct page *page, unsigned int order, > > if (init && !kasan_has_integrated_init()) > > kernel_init_free_pages(page, 1 << order); > > > > - kernel_unpoison_pages(page, 1 << order); > > set_page_owner(page, order, gfp_flags); > > } > > > > > -- Sergei