From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 2/5] mm,thp: stop leaking unreleased file pages Date: Wed, 27 May 2020 22:20:43 -0700 Message-ID: <20200528052043.TKW9wStFk%akpm@linux-foundation.org> References: <20200527222015.62ba8592af63dae12ab58ffe@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:45248 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725764AbgE1FUp (ORCPT ); Thu, 28 May 2020 01:20:45 -0400 In-Reply-To: <20200527222015.62ba8592af63dae12ab58ffe@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: akpm@linux-foundation.org, hannes@cmpxchg.org, hughd@google.com, kirill.shutemov@linux.intel.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, riel@surriel.com, songliubraving@fb.com, stable@vger.kernel.org, torvalds@linux-foundation.org From: Hugh Dickins Subject: mm,thp: stop leaking unreleased file pages When collapse_file() calls try_to_release_page(), it has already isolated the page: so if releasing buffers happens to fail (as it sometimes does), remember to putback_lru_page(): otherwise that page is left unreclaimable and unfreeable, and the file extent uncollapsible. Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2005231837500.1766@eggly.anvils Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS") Signed-off-by: Hugh Dickins Acked-by: Song Liu Acked-by: Kirill A. Shutemov Acked-by: Johannes Weiner Cc: Rik van Riel Cc: [5.4+] Signed-off-by: Andrew Morton --- mm/khugepaged.c | 1 + 1 file changed, 1 insertion(+) --- a/mm/khugepaged.c~mmthp-stop-leaking-unreleased-file-pages +++ a/mm/khugepaged.c @@ -1692,6 +1692,7 @@ static void collapse_file(struct mm_stru if (page_has_private(page) && !try_to_release_page(page, GFP_KERNEL)) { result = SCAN_PAGE_HAS_PRIVATE; + putback_lru_page(page); goto out_unlock; } _