From db5ae363292705d52c5b653d5079a07a6417ef4c Mon Sep 17 00:00:00 2001 From: Wuyun Zhao Date: Thu, 18 Jun 2020 10:58:37 +0800 Subject: [PATCH] f2fs: fix a race condition between f2fs_write_end_io and f2fs_del_fsync_node_entry Under some condition, the __write_node_page will submit a page which is not f2fs_in_warm_node_list and will not call f2fs_add_fsync_node_entry. f2fs_gc continue to run to invoke f2fs_iget -> do_read_inode to read the same node page and set code node, which make f2fs_in_warm_node_list become true, that will cause f2fs_bug_on in f2fs_del_fsync_node_entry when f2fs_write_end_io called. - f2fs_write_end_io - f2fs_iget - do_read_inode - set_cold_node recover cold node flag - f2fs_in_warm_node_list - is_cold_node if node is cold, assume we have added node to fsync_node_list during writepages() - f2fs_del_fsync_node_entry - f2fs_bug_on() due to node page is not in fsync_node_list [ 34.966133] Call trace: [ 34.969902] f2fs_del_fsync_node_entry+0x100/0x108 [ 34.976071] f2fs_write_end_io+0x1e0/0x288 [ 34.981539] bio_endio+0x248/0x270 [ 34.986289] blk_update_request+0x2b0/0x4d8 [ 34.991841] scsi_end_request+0x40/0x440 [ 34.997126] scsi_io_completion+0xa4/0x748 [ 35.002593] scsi_finish_command+0xdc/0x110 [ 35.008143] scsi_softirq_done+0x118/0x150 [ 35.013610] blk_done_softirq+0x8c/0xe8 [ 35.018811] __do_softirq+0x2e8/0x578 [ 35.023828] irq_exit+0xfc/0x120 [ 35.028398] handle_IPI+0x1d8/0x330 [ 35.033233] gic_handle_irq+0x110/0x1d4 [ 35.038433] el1_irq+0xb4/0x130 [ 35.042917] kmem_cache_alloc+0x3f0/0x418 [ 35.048288] radix_tree_node_alloc+0x50/0xf8 [ 35.053933] __radix_tree_create+0xf8/0x188 [ 35.059484] __radix_tree_insert+0x3c/0x128 [ 35.065035] add_gc_inode+0x90/0x118 [ 35.069967] f2fs_gc+0x1b80/0x2d70 [ 35.074718] f2fs_disable_checkpoint+0x94/0x1d0 [ 35.080621] f2fs_fill_super+0x10c4/0x1b88 [ 35.086088] mount_bdev+0x194/0x1e0 [ 35.090923] f2fs_mount+0x40/0x50 [ 35.095589] mount_fs+0xb4/0x190 [ 35.100159] vfs_kern_mount+0x80/0x1d8 [ 35.105260] do_mount+0x478/0xf18 [ 35.109926] ksys_mount+0x90/0xd0 [ 35.114592] __arm64_sys_mount+0x24/0x38 Signed-off-by: Wuyun Zhao Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/inode.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 44582a4db513..33affa788588 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -402,6 +402,7 @@ static int do_read_inode(struct inode *inode) /* try to recover cold bit for non-dir inode */ if (!S_ISDIR(inode->i_mode) && !is_cold_node(node_page)) { + f2fs_wait_on_page_writeback(node_page, NODE, true, true); set_cold_node(node_page, false); set_page_dirty(node_page); }