From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933184AbdCVCmn (ORCPT ); Tue, 21 Mar 2017 22:42:43 -0400 Received: from mail.kernel.org ([198.145.29.136]:39924 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757696AbdCVCmk (ORCPT ); Tue, 21 Mar 2017 22:42:40 -0400 Date: Tue, 21 Mar 2017 22:41:46 -0400 From: Jaegeuk Kim To: Chao Yu Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, chao@kernel.org Subject: Re: [PATCH 1/2] f2fs: introduce __drop_inmem_page Message-ID: <20170322024146.GA71425@jaegeuk.local> References: <20170321120945.76050-1-yuchao0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170321120945.76050-1-yuchao0@huawei.com> User-Agent: Mutt/1.7.0 (2016-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Chao, Please let me make one patch by integrating into my original patch like this. I slightly changed drop_inmem_page() as well. Thanks, >>From 8c242db9b8c01b252290e23827163787f07e01d1 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Fri, 17 Mar 2017 09:55:52 +0800 Subject: [PATCH] f2fs: fix stale ATOMIC_WRITTEN_PAGE private pointer When I forced to enable atomic operations intentionally, I could hit the below panic, since we didn't clear page->private in f2fs_invalidate_page called by file truncation. The panic occurs due to NULL mapping having page->private. BUG: unable to handle kernel paging request at ffffffffffffffff IP: drop_buffers+0x38/0xe0 PGD 5d00c067 PUD 5d00e067 PMD 0 CPU: 3 PID: 1648 Comm: fsstress Tainted: G D OE 4.10.0+ #5 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 task: ffff9151952863c0 task.stack: ffffaaec40db4000 RIP: 0010:drop_buffers+0x38/0xe0 RSP: 0018:ffffaaec40db74c8 EFLAGS: 00010292 Call Trace: ? page_referenced+0x8b/0x170 try_to_free_buffers+0xc5/0xe0 try_to_release_page+0x49/0x50 shrink_page_list+0x8bc/0x9f0 shrink_inactive_list+0x1dd/0x500 ? shrink_active_list+0x2c0/0x430 shrink_node_memcg+0x5eb/0x7c0 shrink_node+0xe1/0x320 do_try_to_free_pages+0xef/0x2e0 try_to_free_pages+0xe9/0x190 __alloc_pages_slowpath+0x390/0xe70 __alloc_pages_nodemask+0x291/0x2b0 alloc_pages_current+0x95/0x140 __page_cache_alloc+0xc4/0xe0 pagecache_get_page+0xab/0x2a0 grab_cache_page_write_begin+0x20/0x40 get_read_data_page+0x2e6/0x4c0 [f2fs] ? f2fs_mark_inode_dirty_sync+0x16/0x30 [f2fs] ? truncate_data_blocks_range+0x238/0x2b0 [f2fs] get_lock_data_page+0x30/0x190 [f2fs] __exchange_data_block+0xaaf/0xf40 [f2fs] f2fs_fallocate+0x418/0xd00 [f2fs] vfs_fallocate+0x157/0x220 SyS_fallocate+0x48/0x80 Signed-off-by: Yunlei He Signed-off-by: Chao Yu [Chao Yu: use INMEM_INVALIDATE for better tracing] Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 2 +- fs/f2fs/f2fs.h | 2 ++ fs/f2fs/segment.c | 30 ++++++++++++++++++++++++++++++ include/trace/events/f2fs.h | 2 ++ 4 files changed, 35 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 1602b4bccae6..e341d446205a 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1951,7 +1951,7 @@ void f2fs_invalidate_page(struct page *page, unsigned int offset, /* This is atomic written page, keep Private */ if (IS_ATOMIC_WRITTEN_PAGE(page)) - return; + return drop_inmem_page(inode, page); set_page_private(page, 0); ClearPagePrivate(page); diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 0a6e115562f6..264c219f41a5 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -722,6 +722,7 @@ enum page_type { META_FLUSH, INMEM, /* the below types are used by tracepoints only. */ INMEM_DROP, + INMEM_INVALIDATE, INMEM_REVOKE, IPU, OPU, @@ -2184,6 +2185,7 @@ void destroy_node_manager_caches(void); */ void register_inmem_page(struct inode *inode, struct page *page); void drop_inmem_pages(struct inode *inode); +void drop_inmem_page(struct inode *inode, struct page *page); int commit_inmem_pages(struct inode *inode); void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need); void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi); diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 4d7bf84dc393..cb6d9ed634a3 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -250,6 +250,36 @@ void drop_inmem_pages(struct inode *inode) stat_dec_atomic_write(inode); } +void drop_inmem_page(struct inode *inode, struct page *page) +{ + struct f2fs_inode_info *fi = F2FS_I(inode); + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + struct list_head *head = &fi->inmem_pages; + struct inmem_pages *cur = NULL; + + f2fs_bug_on(sbi, !IS_ATOMIC_WRITTEN_PAGE(page)); + + mutex_lock(&fi->inmem_lock); + list_for_each_entry(cur, head, list) { + if (cur->page == page) + break; + } + + f2fs_bug_on(sbi, !cur || cur->page != page); + list_del(&cur->list); + mutex_unlock(&fi->inmem_lock); + + dec_page_count(sbi, F2FS_INMEM_PAGES); + kmem_cache_free(inmem_entry_slab, cur); + + ClearPageUptodate(page); + set_page_private(page, 0); + ClearPagePrivate(page); + f2fs_put_page(page, 0); + + trace_f2fs_commit_inmem_page(page, INMEM_INVALIDATE); +} + static int __commit_inmem_pages(struct inode *inode, struct list_head *revoke_list) { diff --git a/include/trace/events/f2fs.h b/include/trace/events/f2fs.h index c80fcad0a6c9..96139021b6bc 100644 --- a/include/trace/events/f2fs.h +++ b/include/trace/events/f2fs.h @@ -15,6 +15,7 @@ TRACE_DEFINE_ENUM(META); TRACE_DEFINE_ENUM(META_FLUSH); TRACE_DEFINE_ENUM(INMEM); TRACE_DEFINE_ENUM(INMEM_DROP); +TRACE_DEFINE_ENUM(INMEM_INVALIDATE); TRACE_DEFINE_ENUM(IPU); TRACE_DEFINE_ENUM(OPU); TRACE_DEFINE_ENUM(CURSEG_HOT_DATA); @@ -51,6 +52,7 @@ TRACE_DEFINE_ENUM(CP_DISCARD); { META_FLUSH, "META_FLUSH" }, \ { INMEM, "INMEM" }, \ { INMEM_DROP, "INMEM_DROP" }, \ + { INMEM_INVALIDATE, "INMEM_INVALIDATE" }, \ { INMEM_REVOKE, "INMEM_REVOKE" }, \ { IPU, "IN-PLACE" }, \ { OPU, "OUT-OF-PLACE" }) -- 2.11.0