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 9E7E7C433EF for ; Thu, 10 Feb 2022 13:18:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E20BD6B0075; Thu, 10 Feb 2022 08:18:29 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id DCF306B007B; Thu, 10 Feb 2022 08:18:29 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CBDD66B007D; Thu, 10 Feb 2022 08:18:29 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0221.hostedemail.com [216.40.44.221]) by kanga.kvack.org (Postfix) with ESMTP id BD5B36B0075 for ; Thu, 10 Feb 2022 08:18:29 -0500 (EST) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 7D8DD181AC9CC for ; Thu, 10 Feb 2022 13:18:29 +0000 (UTC) X-FDA: 79126924338.13.26B2E00 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf11.hostedemail.com (Postfix) with ESMTP id B4AE340005 for ; Thu, 10 Feb 2022 13:18:28 +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=07cBonba1DbDiUBmK2dO6ItNWq9O714rRPMKjF5tL9Q=; b=o4o0vDtZV6FxU8CZGgzhaGJWwr bTeuRXjT7it0pixyf6hKUpANq1wEjPl/ZnZc/cra8RkSuFNu74KAfCUHf+EiMwUfd2QVf0KWYzTnk 6Hk6hBsEc6vHbY3x0IEj9ex4TCVjwbPn7kmfTULGPhQvIQIGCMwMCDd/efdm9Q8J6EGq3elPKZ7C1 iHM++X6fXUC4Nb+sqFIVml+OOgrcUHa5B8Rk++WXQRGX3P/tnNCnp0RjlfHlEU7g0WvCSCItCEcUL ONBwHn82hpsY9Fg4PyrNW1qfcqvI0sgfIULEc3CtyYbMuthoJSHg4BA53HQOHaOQxgF/r9UzumNtG vaNLLp2A==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nI9Kz-009SYN-UO; Thu, 10 Feb 2022 13:18:17 +0000 Date: Thu, 10 Feb 2022 13:18:17 +0000 From: Matthew Wilcox To: Huangzhaoyang Cc: Andrew Morton , Zhaoyang Huang , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH] mm: record context on page->mapping Message-ID: References: <1644483715-7981-1-git-send-email-huangzhaoyang@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1644483715-7981-1-git-send-email-huangzhaoyang@gmail.com> X-Stat-Signature: a7fnr9ngzmgkt9369u4hbcgr67u7iaq5 Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=o4o0vDtZ; spf=none (imf11.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: B4AE340005 X-HE-Tag: 1644499108-706397 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 Thu, Feb 10, 2022 at 05:01:55PM +0800, Huangzhaoyang wrote: > From: Zhaoyang Huang > > Since page->mapping is vacant in the pages which used by kernel(drivers etc) > Have it record current context to help tracking the page's owner in system > memory dump. > > Signed-off-by: Zhaoyang Huang > --- > mm/page_alloc.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index c595274..2757d10 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -2430,6 +2430,8 @@ static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags > set_page_pfmemalloc(page); > else > clear_page_pfmemalloc(page); > + > + page->mapping = (struct address_space *)current; > } You didn't actually try this patch, did you? See page_expected_state(). Or, I don't know, just boot it.