From fbb24a3a915f105016f1c828476be11aceac8504 Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Wed, 20 Jun 2012 12:52:57 -0700 Subject: nilfs2: ensure proper cache clearing for gc-inodes A gc-inode is a pseudo inode used to buffer the blocks to be moved by garbage collection. Block caches of gc-inodes must be cleared every time a garbage collection function (nilfs_clean_segments) completes. Otherwise, stale blocks buffered in the caches may be wrongly reused in successive calls of the GC function. For user files, this is not a problem because their gc-inodes are distinguished by a checkpoint number as well as an inode number. They never buffer different blocks if either an inode number, a checkpoint number, or a block offset differs. However, gc-inodes of sufile, cpfile and DAT file can store different data for the same block offset. Thus, the nilfs_clean_segments function can move incorrect block for these meta-data files if an old block is cached. I found this is really causing meta-data corruption in nilfs. This fixes the issue by ensuring cache clear of gc-inodes and resolves reported GC problems including checkpoint file corruption, b-tree corruption, and the following warning during GC. nilfs_palloc_freev: entry number 307234 already freed. ... Signed-off-by: Ryusuke Konishi Tested-by: Ryusuke Konishi Cc: [2.6.37+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/nilfs2/gcinode.c | 2 ++ fs/nilfs2/segment.c | 2 ++ 2 files changed, 4 insertions(+) (limited to 'fs') diff --git a/fs/nilfs2/gcinode.c b/fs/nilfs2/gcinode.c index 08a07a218d26..57ceaf33d177 100644 --- a/fs/nilfs2/gcinode.c +++ b/fs/nilfs2/gcinode.c @@ -191,6 +191,8 @@ void nilfs_remove_all_gcinodes(struct the_nilfs *nilfs) while (!list_empty(head)) { ii = list_first_entry(head, struct nilfs_inode_info, i_dirty); list_del_init(&ii->i_dirty); + truncate_inode_pages(&ii->vfs_inode.i_data, 0); + nilfs_btnode_cache_clear(&ii->i_btnode_cache); iput(&ii->vfs_inode); } } diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c index 0e72ad6f22aa..88e11fb346b6 100644 --- a/fs/nilfs2/segment.c +++ b/fs/nilfs2/segment.c @@ -2309,6 +2309,8 @@ nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head) if (!test_bit(NILFS_I_UPDATED, &ii->i_state)) continue; list_del_init(&ii->i_dirty); + truncate_inode_pages(&ii->vfs_inode.i_data, 0); + nilfs_btnode_cache_clear(&ii->i_btnode_cache); iput(&ii->vfs_inode); } } -- cgit v1.2.2 From 4fe7efdbdfb1c7e7a7f31decfd831c0f31d37091 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Wed, 20 Jun 2012 12:53:01 -0700 Subject: mm: correctly synchronize rss-counters at exit/exec do_exit() and exec_mmap() call sync_mm_rss() before mm_release() does put_user(clear_child_tid) which can update task->rss_stat and thus make mm->rss_stat inconsistent. This triggers the "BUG:" printk in check_mm(). Let's fix this bug in the safest way, and optimize/cleanup this later. Reported-by: Markus Trippelsdorf Signed-off-by: Konstantin Khlebnikov Cc: Oleg Nesterov Cc: KAMEZAWA Hiroyuki Cc: Hugh Dickins Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/exec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/exec.c b/fs/exec.c index a79786a8d2c8..da27b91ff1e8 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -819,10 +819,10 @@ static int exec_mmap(struct mm_struct *mm) /* Notify parent that we're no longer interested in the old VM */ tsk = current; old_mm = current->mm; - sync_mm_rss(old_mm); mm_release(tsk, old_mm); if (old_mm) { + sync_mm_rss(old_mm); /* * Make sure that if there is a core dump in progress * for the old mm, we get out and die instead of going -- cgit v1.2.2