+ mm-fix-madivse_pageout-mishandling-on-non-lru-page.patch added to mm-hotfixes-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

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The patch titled
     Subject: mm: fix madivse_pageout mishandling on non-LRU page
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-fix-madivse_pageout-mishandling-on-non-lru-page.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-fix-madivse_pageout-mishandling-on-non-lru-page.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Minchan Kim <minchan@kernel.org>
Subject: mm: fix madivse_pageout mishandling on non-LRU page
Date: Thu, 8 Sep 2022 08:12:04 -0700

MADV_PAGEOUT tries to isolate non-LRU pages and gets a warning from
isolate_lru_page below.

Fix it by checking PageLRU in advance.

------------[ cut here ]------------
trying to isolate tail page
WARNING: CPU: 0 PID: 6175 at mm/folio-compat.c:158 isolate_lru_page+0x130/0x140
Modules linked in:
CPU: 0 PID: 6175 Comm: syz-executor.0 Not tainted 5.18.12 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:isolate_lru_page+0x130/0x140

Link: https://lore.kernel.org/linux-mm/485f8c33.2471b.182d5726afb.Coremail.hantianshuo@iie.ac.cn/
Link: https://lkml.kernel.org/r/20220908151204.762596-1-minchan@kernel.org
Fixes: 1a4e58cce84e ("mm: introduce MADV_PAGEOUT")
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: 韩天ç`• <hantianshuo@iie.ac.cn>
Suggested-by: Yang Shi <shy828301@gmail.com>
Acked-by: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/madvise.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/mm/madvise.c~mm-fix-madivse_pageout-mishandling-on-non-lru-page
+++ a/mm/madvise.c
@@ -451,8 +451,11 @@ regular_page:
 			continue;
 		}
 
-		/* Do not interfere with other mappings of this page */
-		if (page_mapcount(page) != 1)
+		/*
+		 * Do not interfere with other mappings of this page and
+		 * non-LRU page.
+		 */
+		if (!PageLRU(page) || page_mapcount(page) != 1)
 			continue;
 
 		VM_BUG_ON_PAGE(PageTransCompound(page), page);
_

Patches currently in -mm which might be from minchan@kernel.org are

mm-fix-madivse_pageout-mishandling-on-non-lru-page.patch