Hello, syzbot found the following issue on: HEAD commit: 05a59d79 Merge git://git.kernel.org:/pub/scm/linux/kernel/.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=100de152d00000 kernel config: https://syzkaller.appspot.com/x/.config?x=b28ee088c7349c4d dashboard link: https://syzkaller.appspot.com/bug?extid=a464ba0296692a4d2692 userspace arch: arm Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a464ba0296692a4d2692@xxxxxxxxxxxxxxxxxxxxxxxxx ================================ WARNING: inconsistent lock state 5.12.0-rc2-syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-R} usage. kworker/u4:0/7 [HC0[0]:SC1[1]:HE0:SE0] takes: 8f87826c (&inode->i_size_seqcount){+.+-}-{0:0}, at: end_bio_bh_io_sync+0x38/0x54 fs/buffer.c:3006 {SOFTIRQ-ON-W} state was registered at: lock_acquire.part.0+0xf0/0x41c kernel/locking/lockdep.c:5510 lock_acquire+0x6c/0x74 kernel/locking/lockdep.c:5483 do_write_seqcount_begin_nested include/linux/seqlock.h:520 [inline] do_write_seqcount_begin include/linux/seqlock.h:545 [inline] i_size_write include/linux/fs.h:863 [inline] set_capacity+0x13c/0x1f8 block/genhd.c:50 brd_alloc+0x130/0x180 drivers/block/brd.c:401 brd_init+0xcc/0x1e0 drivers/block/brd.c:500 do_one_initcall+0x8c/0x59c init/main.c:1226 do_initcall_level init/main.c:1299 [inline] do_initcalls init/main.c:1315 [inline] do_basic_setup init/main.c:1335 [inline] kernel_init_freeable+0x2cc/0x330 init/main.c:1537 kernel_init+0x10/0x120 init/main.c:1424 ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:158 0x0 irq event stamp: 2783413 hardirqs last enabled at (2783412): [<802011ec>] __do_softirq+0xf4/0x7ac kernel/softirq.c:329 hardirqs last disabled at (2783413): [<8277d260>] __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:157 [inline] hardirqs last disabled at (2783413): [<8277d260>] _raw_read_lock_irqsave+0x84/0x88 kernel/locking/spinlock.c:231 softirqs last enabled at (2783410): [<826b5050>] spin_unlock_bh include/linux/spinlock.h:399 [inline] softirqs last enabled at (2783410): [<826b5050>] batadv_nc_purge_paths+0x10c/0x148 net/batman-adv/network-coding.c:467 softirqs last disabled at (2783411): [<8024ddfc>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] softirqs last disabled at (2783411): [<8024ddfc>] do_softirq kernel/softirq.c:248 [inline] softirqs last disabled at (2783411): [<8024ddfc>] do_softirq+0xd8/0xe4 kernel/softirq.c:235 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&inode->i_size_seqcount); <Interrupt> lock(&inode->i_size_seqcount); *** DEADLOCK *** 3 locks held by kworker/u4:0/7: #0: 88c622a8 ((wq_completion)bat_events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: 88c622a8 ((wq_completion)bat_events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: 88c622a8 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x214/0x998 kernel/workqueue.c:2246 #1: 85147ef8 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #1: 85147ef8 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #1: 85147ef8 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x214/0x998 kernel/workqueue.c:2246 #2: 8f878010 (&ni->size_lock){...-}-{2:2}, at: ntfs_end_buffer_async_read+0x6c/0x558 fs/ntfs/aops.c:66 stack backtrace: CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 5.12.0-rc2-syzkaller #0 Hardware name: ARM-Versatile Express Workqueue: bat_events batadv_nc_worker Backtrace: [<82740468>] (dump_backtrace) from [<827406dc>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:252) r7:00000080 r6:60000193 r5:00000000 r4:8422a3c4 [<827406c4>] (show_stack) from [<82751b58>] (__dump_stack lib/dump_stack.c:79 [inline]) [<827406c4>] (show_stack) from [<82751b58>] (dump_stack+0xb8/0xe8 lib/dump_stack.c:120) [<82751aa0>] (dump_stack) from [<82742918>] (print_usage_bug.part.0+0x228/0x230 kernel/locking/lockdep.c:3806) r7:8512e868 r6:82803274 r5:848a3628 r4:8512e180 [<827426f0>] (print_usage_bug.part.0) from [<802bb4b8>] (print_usage_bug kernel/locking/lockdep.c:3776 [inline]) [<827426f0>] (print_usage_bug.part.0) from [<802bb4b8>] (valid_state kernel/locking/lockdep.c:3818 [inline]) [<827426f0>] (print_usage_bug.part.0) from [<802bb4b8>] (mark_lock_irq kernel/locking/lockdep.c:4021 [inline]) [<827426f0>] (print_usage_bug.part.0) from [<802bb4b8>] (mark_lock.part.0+0xc34/0x136c kernel/locking/lockdep.c:4478) r10:84a42fe8 r9:84437748 r8:00000000 r7:844372d4 r6:00000006 r5:8512e868 r4:00000005 [<802ba884>] (mark_lock.part.0) from [<802bca0c>] (mark_lock kernel/locking/lockdep.c:4442 [inline]) [<802ba884>] (mark_lock.part.0) from [<802bca0c>] (mark_usage kernel/locking/lockdep.c:4365 [inline]) [<802ba884>] (mark_lock.part.0) from [<802bca0c>] (__lock_acquire+0xa84/0x3318 kernel/locking/lockdep.c:4854) r10:8512e868 r9:8512e180 r8:00000001 r7:00040000 r6:0000023a r5:848a3628 r4:00000000 [<802bbf88>] (__lock_acquire) from [<802bfe90>] (lock_acquire.part.0+0xf0/0x41c kernel/locking/lockdep.c:5510) r10:00000080 r9:60000193 r8:00000000 r7:00000000 r6:83ecd680 r5:83ecd680 r4:85147b68 [<802bfda0>] (lock_acquire.part.0) from [<802c0228>] (lock_acquire+0x6c/0x74 kernel/locking/lockdep.c:5483) r10:8052dcb4 r9:00000000 r8:00000001 r7:00000002 r6:00000000 r5:00000000 r4:8f87826c [<802c01bc>] (lock_acquire) from [<808b1af8>] (seqcount_lockdep_reader_access include/linux/seqlock.h:103 [inline]) [<802c01bc>] (lock_acquire) from [<808b1af8>] (i_size_read include/linux/fs.h:838 [inline]) [<802c01bc>] (lock_acquire) from [<808b1af8>] (ntfs_end_buffer_async_read+0xb4/0x558 fs/ntfs/aops.c:68) r10:8f878000 r9:60000193 r8:8052dcb4 r7:8f87826c r6:df3f0dc0 r5:8a4e46c0 r4:8f8781c8 [<808b1a44>] (ntfs_end_buffer_async_read) from [<8052dcb4>] (end_bio_bh_io_sync+0x38/0x54 fs/buffer.c:3006) r10:00000200 r9:00000200 r8:0000000a r7:00000000 r6:8725ad00 r5:8a4e46c0 r4:8b08c3c0 [<8052dc7c>] (end_bio_bh_io_sync) from [<80f0f638>] (bio_endio+0x124/0x338 block/bio.c:1436) r5:80f0f84c r4:8b08c3c0 [<80f0f514>] (bio_endio) from [<80f166cc>] (req_bio_endio block/blk-core.c:265 [inline]) [<80f0f514>] (bio_endio) from [<80f166cc>] (blk_update_request+0x220/0x724 block/blk-core.c:1456) r9:00000200 r8:0000000a r7:00000000 r6:8725ad00 r5:00000200 r4:8b08c3c0 [<80f164ac>] (blk_update_request) from [<80f23128>] (blk_mq_end_request+0x1c/0x144 block/blk-mq.c:564) r10:00000010 r9:85146000 r8:8404ec98 r7:00000000 r6:00000004 r5:8725ad00 r4:8725ad00 [<80f2310c>] (blk_mq_end_request) from [<811d1e2c>] (lo_complete_rq+0x98/0xd4 drivers/block/loop.c:497) r7:00000001 r6:00000004 r5:8725ad00 r4:ffffffc8 [<811d1d94>] (lo_complete_rq) from [<80f21ab4>] (blk_complete_reqs+0x5c/0x68 block/blk-mq.c:576) r5:00000005 r4:ffffffc8 [<80f21a58>] (blk_complete_reqs) from [<80f21b1c>] (blk_done_softirq+0x2c/0x30 block/blk-mq.c:581) r5:00000005 r4:83ed846c [<80f21af0>] (blk_done_softirq) from [<802012fc>] (__do_softirq+0x204/0x7ac kernel/softirq.c:345) r5:00000005 r4:84004090 [<802010f8>] (__do_softirq) from [<8024ddfc>] (do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline]) [<802010f8>] (__do_softirq) from [<8024ddfc>] (do_softirq kernel/softirq.c:248 [inline]) [<802010f8>] (__do_softirq) from [<8024ddfc>] (do_softirq+0xd8/0xe4 kernel/softirq.c:235) r10:00000088 r9:88c9c2d0 r8:8aaaeac0 r7:00000000 r6:ffffe000 r5:826b5050 r4:60000193 [<8024dd24>] (do_softirq) from [<8024e048>] (__local_bh_enable_ip+0x240/0x244 kernel/softirq.c:198) r5:826b5050 r4:00000001 [<8024de08>] (__local_bh_enable_ip) from [<8277cf8c>] (__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline]) [<8024de08>] (__local_bh_enable_ip) from [<8277cf8c>] (_raw_spin_unlock_bh+0x34/0x38 kernel/locking/spinlock.c:207) r7:00000000 r6:00000015 r5:88c9c2d0 r4:826b5050 [<8277cf58>] (_raw_spin_unlock_bh) from [<826b5050>] (spin_unlock_bh include/linux/spinlock.h:399 [inline]) [<8277cf58>] (_raw_spin_unlock_bh) from [<826b5050>] (batadv_nc_purge_paths+0x10c/0x148 net/batman-adv/network-coding.c:467) r5:8aae9740 r4:826b511c [<826b4f44>] (batadv_nc_purge_paths) from [<826b57b0>] (batadv_nc_worker+0x304/0x470 net/batman-adv/network-coding.c:716) r10:00000088 r9:8404ec98 r8:8aae9d28 r7:88a9c200 r6:84006d00 r5:8aaea000 r4:8aae9740 [<826b54ac>] (batadv_nc_worker) from [<802696a4>] (process_one_work+0x2d4/0x998 kernel/workqueue.c:2275) r10:00000088 r9:8404ec98 r8:84367a02 r7:88a9c200 r6:85020000 r5:850c9700 r4:8aae9d28 [<802693d0>] (process_one_work) from [<80269dcc>] (worker_thread+0x64/0x54c kernel/workqueue.c:2421) r10:00000088 r9:85146000 r8:84006d00 r7:85020038 r6:850c9714 r5:85020000 r4:850c9700 [<80269d68>] (worker_thread) from [<80271f40>] (kthread+0x184/0x1a4 kernel/kthread.c:292) r10:8511be34 r9:850c9700 r8:80269d68 r7:00000000 r6:85146000 r5:850cee40 r4:850c9780 [<80271dbc>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:158) Exception stack(0x85147fb0 to 0x85147ff8) 7fa0: 00000000 00000000 00000000 00000000 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000 r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80271dbc r4:850cee40 --- This report is generated by a bot. 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