From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:46986 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938791AbcKQKen (ORCPT ); Thu, 17 Nov 2016 05:34:43 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hugh Dickins , "Kirill A. Shutemov" , Andrew Morton , Linus Torvalds Subject: [PATCH 4.8 06/92] shmem: fix pageflags after swapping DMA32 object Date: Thu, 17 Nov 2016 11:31:39 +0100 Message-Id: <20161117103224.484350267@linuxfoundation.org> In-Reply-To: <20161117103224.218007793@linuxfoundation.org> References: <20161117103224.218007793@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hugh Dickins commit 9956edf37e65e93fbb76dcff1236dff2323d306a upstream. If shmem_alloc_page() does not set PageLocked and PageSwapBacked, then shmem_replace_page() needs to do so for itself. Without this, it puts newpage on the wrong lru, re-unlocks the unlocked newpage, and system descends into "Bad page" reports and freeze; or if CONFIG_DEBUG_VM=y, it hits an earlier VM_BUG_ON_PAGE(!PageLocked), depending on config. But shmem_replace_page() is not a common path: it's only called when swapin (or swapoff) finds the page was already read into an unsuitable zone: usually all zones are suitable, but gem objects for a few drm devices (gma500, omapdrm, crestline, broadwater) require zone DMA32 if there's more than 4GB of ram. Fixes: 800d8c63b2e9 ("shmem: add huge pages support") Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1611062003510.11253@eggly.anvils Signed-off-by: Hugh Dickins Acked-by: Kirill A. Shutemov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/shmem.c | 2 ++ 1 file changed, 2 insertions(+) --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1483,6 +1483,8 @@ static int shmem_replace_page(struct pag copy_highpage(newpage, oldpage); flush_dcache_page(newpage); + __SetPageLocked(newpage); + __SetPageSwapBacked(newpage); SetPageUptodate(newpage); set_page_private(newpage, swap_index); SetPageSwapCache(newpage);