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 33183CD1288 for ; Sat, 30 Mar 2024 09:16:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9E4D96B0083; Sat, 30 Mar 2024 05:16:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 96DBB6B0087; Sat, 30 Mar 2024 05:16:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 80DC16B0088; Sat, 30 Mar 2024 05:16:44 -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 5C7466B0083 for ; Sat, 30 Mar 2024 05:16:44 -0400 (EDT) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id B86E61A11E7 for ; Sat, 30 Mar 2024 09:16:43 +0000 (UTC) X-FDA: 81953150286.03.9D58B90 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf14.hostedemail.com (Postfix) with ESMTP id B6266100007 for ; Sat, 30 Mar 2024 09:16:40 +0000 (UTC) Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=linuxfoundation.org header.s=korg header.b=EW8qlZmK; dmarc=pass (policy=none) header.from=linuxfoundation.org; spf=pass (imf14.hostedemail.com: domain of gregkh@linuxfoundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1711790201; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=7EuMLjOFoGnyALTYcUODftJ02WS0kg15CRkNkYNIvYw=; b=vawYUKGYwcbOi+/OWVJ/jI9J4CTnWxVHDyAh+9aFRiGSrahsVCKRCr7J0YhfXPUrANOKtH YPfnwBd3hhdokMkULxg3OGpmilSl/wHaovs3ndwiuZA26Qx2M1owMML0J0jiIU9F2OwJYo FtwespU6jPcFtr7KNugfmefTURwt1mY= ARC-Authentication-Results: i=1; imf14.hostedemail.com; dkim=pass header.d=linuxfoundation.org header.s=korg header.b=EW8qlZmK; dmarc=pass (policy=none) header.from=linuxfoundation.org; spf=pass (imf14.hostedemail.com: domain of gregkh@linuxfoundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1711790201; a=rsa-sha256; cv=none; b=E4qiHcRbYMU9CQWQ8vZmqdft3BoqtvGrS3Tqac1ggS3g+VrMiKsXd3Vm4bDgQPWSyLGV6Y CVFxwe1UW5hUY0j5JP/GqxwGWT86QsGgQqgzWixv4pgEq3qTN26nmWllCrSFueYHdNeBEV k3z3ZonZRV5qXawJWwkOUTE9pTSzO6Q= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id A3EF8CE0022; Sat, 30 Mar 2024 09:16:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74C26C433F1; Sat, 30 Mar 2024 09:16:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1711790195; bh=p7IQwXgdmSvNeGE0lgYdvZsmVCtEOjxj54T6NflUYfk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=EW8qlZmK27kLUWipiBr/AjZwaGDKpcaT5Qht1vlSYnfXQFUzokgxu9WZklObw+3Pk Gn6I7MCp/O9COzzdbnS0GmaQspbUxmPcdwbeL7KzqScsMRepzieyOf7+fExIiztzEG E08L0MLZBa6N1m4ETdtvcoQdzZT4GpJe5WpkPLas= Date: Sat, 30 Mar 2024 10:16:32 +0100 From: Greg KH To: Zi Yan Cc: stable@vger.kernel.org, linux-mm@kvack.org, Charan Teja Kalla , "Matthew Wilcox (Oracle)" , David Hildenbrand , Andrew Morton , Huang Ying , Naoya Horiguchi Subject: Re: [PATCH STABLE v4.19.y] mm/migrate: set swap entry values of THP tail pages properly. Message-ID: <2024033024-degrease-untried-0594@gregkh> References: <20240306155052.118007-1-zi.yan@sent.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240306155052.118007-1-zi.yan@sent.com> X-Rspamd-Queue-Id: B6266100007 X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: ky1x9n1m4pkdn7wfb5t3yfx5q1hrx1oh X-HE-Tag: 1711790200-830922 X-HE-Meta: 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 SxyZ0nW0 DvLREkNJLJqDEIbVUYkjobdg+zD9RH1gU9yZ6rjT9kwN/DXlCR1a61mlwMWjQyTtkX47UiYGwnd91DjHhbwSMhwVnIw0jTX0Ch8ckGjHpxkcOZ8Ayxmm6OMbtdfqz4z1k+uf68vH8yPsQYrGtmDNGI9t0aih4COCwSHvwMPhuRHF1lXs5WiuVm4l9C56SEHP4RT/SdMbaOtgXkJ1Cn4G42lsUy0ePoIDZf0SmJdmfdq+hCGfdHm60mQ1O8j7W/Xlfh1vzF5XnoAEYLocij1/Gwn6H0I34zJmaOl9Z7hxbKUdaXeJM3Q5NC0YNjRU9e1b779oumiLcbEZa8wF7r2h0/r580inCulDn7XXnQ9tlI0JqPt00ucU1Su5sUw== 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: List-Subscribe: List-Unsubscribe: On Wed, Mar 06, 2024 at 10:50:52AM -0500, Zi Yan wrote: > From: Zi Yan > > The tail pages in a THP can have swap entry information stored in their > private field. When migrating to a new page, all tail pages of the new > page need to update ->private to avoid future data corruption. > > This fix is stable-only, since after commit 07e09c483cbe ("mm/huge_memory: > work on folio->swap instead of page->private when splitting folio"), > subpages of a swapcached THP no longer requires the maintenance. > > Adding THPs to the swapcache was introduced in commit > 38d8b4e6bdc87 ("mm, THP, swap: delay splitting THP during swap out"), > where each subpage of a THP added to the swapcache had its own swapcache > entry and required the ->private field to point to the correct swapcache > entry. Later, when THP migration functionality was implemented in commit > 616b8371539a6 ("mm: thp: enable thp migration in generic path"), > it initially did not handle the subpages of swapcached THPs, failing to > update their ->private fields or replace the subpage pointers in the > swapcache. Subsequently, commit e71769ae5260 ("mm: enable thp migration > for shmem thp") addressed the swapcache update aspect. This patch fixes > the update of subpage ->private fields. > > Closes: https://lore.kernel.org/linux-mm/1707814102-22682-1-git-send-email-quic_charante@quicinc.com/ > Fixes: 616b8371539a ("mm: thp: enable thp migration in generic path") > Signed-off-by: Zi Yan > Acked-by: David Hildenbrand > --- > mm/migrate.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/mm/migrate.c b/mm/migrate.c > index 171573613c39..893ea04498f7 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -514,8 +514,12 @@ int migrate_page_move_mapping(struct address_space *mapping, > if (PageSwapBacked(page)) { > __SetPageSwapBacked(newpage); > if (PageSwapCache(page)) { > + int i; > + > SetPageSwapCache(newpage); > - set_page_private(newpage, page_private(page)); > + for (i = 0; i < (1 << compound_order(page)); i++) > + set_page_private(newpage + i, > + page_private(page + i)); > } > } else { > VM_BUG_ON_PAGE(PageSwapCache(page), page); > -- > 2.43.0 > > All now queued up, thanks. greg k-h