On 7/31/19 6:13 AM, SunKe wrote:
From: Munehisa Kamata kamatam@amazon.com
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.
Applied, thanks.