On Wed, Jul 31, 2019 at 08:13:10PM +0800, SunKe wrote: > From: Munehisa Kamata <kamatam@xxxxxxxxxx> > > Commit abbbdf12497d ("replace kill_bdev() with __invalidate_device()") > once did this, but 29eaadc03649 ("nbd: stop using the bdev everywhere") > resurrected kill_bdev() and it has been there since then. So buffer_head > mappings still get killed on a server disconnection, and we can still > hit the BUG_ON on a filesystem on the top of the nbd device. > > EXT4-fs (nbd0): mounted filesystem with ordered data mode. Opts: (null) > block nbd0: Receive control failed (result -32) > block nbd0: shutting down sockets > print_req_error: I/O error, dev nbd0, sector 66264 flags 3000 > EXT4-fs warning (device nbd0): htree_dirblock_to_tree:979: inode #2: lblock 0: comm ls: error -5 reading directory block > print_req_error: I/O error, dev nbd0, sector 2264 flags 3000 > EXT4-fs error (device nbd0): __ext4_get_inode_loc:4690: inode #2: block 283: comm ls: unable to read itable block > EXT4-fs error (device nbd0) in ext4_reserve_inode_write:5894: IO failure > ------------[ cut here ]------------ > kernel BUG at fs/buffer.c:3057! > invalid opcode: 0000 [#1] SMP PTI > CPU: 7 PID: 40045 Comm: jbd2/nbd0-8 Not tainted 5.1.0-rc3+ #4 > Hardware name: Amazon EC2 m5.12xlarge/, BIOS 1.0 10/16/2017 > RIP: 0010:submit_bh_wbc+0x18b/0x190 > ... > Call Trace: > jbd2_write_superblock+0xf1/0x230 [jbd2] > ? account_entity_enqueue+0xc5/0xf0 > jbd2_journal_update_sb_log_tail+0x94/0xe0 [jbd2] > jbd2_journal_commit_transaction+0x12f/0x1d20 [jbd2] > ? __switch_to_asm+0x40/0x70 > ... > ? lock_timer_base+0x67/0x80 > kjournald2+0x121/0x360 [jbd2] > ? remove_wait_queue+0x60/0x60 > kthread+0xf8/0x130 > ? commit_timeout+0x10/0x10 [jbd2] > ? kthread_bind+0x10/0x10 > ret_from_fork+0x35/0x40 > > With __invalidate_device(), I no longer hit the BUG_ON with sync or > unmount on the disconnected device. > Jeeze I swear I see this same patch go by every 6 months or so, not sure what happens to it. Anyway Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx> Thanks, Josef