bisecting fixing commit since 811218eceeaa7618652e1b8d11caeff67ab42072 building syzkaller on 624dad51316f9973e1349b6c71e789737d1e00d9 testing commit 811218eceeaa7618652e1b8d11caeff67ab42072 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 313c854c4c98a50095576113c231aae2aa079883aef8591fbbde340be5a239f7 run #0: crashed: INFO: task hung in blkdev_put run #1: crashed: INFO: task hung in truncate_inode_pages_range run #2: crashed: INFO: task hung in truncate_inode_pages_range run #3: crashed: INFO: task hung in truncate_inode_pages_range run #4: crashed: INFO: task hung in truncate_inode_pages_range run #5: crashed: INFO: task hung in truncate_inode_pages_range run #6: crashed: INFO: task hung in truncate_inode_pages_range run #7: crashed: INFO: task hung in truncate_inode_pages_range run #8: crashed: INFO: task hung in truncate_inode_pages_range run #9: crashed: INFO: task hung in truncate_inode_pages_range run #10: crashed: INFO: task hung in truncate_inode_pages_range run #11: crashed: INFO: task hung in truncate_inode_pages_range run #12: crashed: INFO: task hung in truncate_inode_pages_range run #13: crashed: INFO: task hung in truncate_inode_pages_range run #14: crashed: INFO: task hung in truncate_inode_pages_range run #15: crashed: INFO: task hung in truncate_inode_pages_range run #16: crashed: INFO: task hung in truncate_inode_pages_range run #17: crashed: INFO: task hung in truncate_inode_pages_range run #18: crashed: INFO: task hung in truncate_inode_pages_range run #19: crashed: INFO: task hung in truncate_inode_pages_range testing current HEAD c2276d585654e8d573366c29c565043ec36adf63 testing commit c2276d585654e8d573366c29c565043ec36adf63 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: db0ea19cdd9ac2536239c57d66fafc5e40490f8c7dbeebfbcd44ae5d0ed151d6 run #0: crashed: INFO: task hung in blk_freeze_queue run #1: crashed: INFO: task hung in nbd_ioctl run #2: crashed: INFO: task hung in nbd_ioctl run #3: crashed: INFO: task hung in nbd_ioctl run #4: crashed: INFO: task hung in nbd_ioctl run #5: crashed: INFO: task hung in nbd_ioctl run #6: crashed: INFO: task hung in nbd_ioctl run #7: crashed: INFO: task hung in nbd_ioctl run #8: crashed: INFO: task hung in nbd_ioctl run #9: crashed: INFO: task hung in blk_freeze_queue revisions tested: 2, total time: 33m51.322455722s (build: 18m3.538079323s, test: 15m14.716457823s) the crash still happens on HEAD commit msg: Linux 4.19.208 crash: INFO: task hung in blk_freeze_queue Bluetooth: hci4: command 0x0406 tx timeout Bluetooth: hci5: command 0x0406 tx timeout Bluetooth: hci2: command 0x0406 tx timeout Bluetooth: hci3: command 0x0406 tx timeout Bluetooth: hci0: command 0x0406 tx timeout INFO: task syz-executor.2:9853 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28552 9853 8427 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 blk_mq_freeze_queue_wait+0x105/0x220 block/blk-mq.c:152 blk_freeze_queue+0x3d/0x60 block/blk-mq.c:181 blk_mq_freeze_queue+0x9/0x10 block/blk-mq.c:190 nbd_add_socket+0x109/0x840 drivers/block/nbd.c:973 __nbd_ioctl drivers/block/nbd.c:1320 [inline] nbd_ioctl+0x4fd/0xb30 drivers/block/nbd.c:1387 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: Bad RIP value. RSP: 002b:00007fe1e2c12188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000465b09 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007fffcb27b30f R14: 00007fe1e2c12300 R15: 0000000000022000 INFO: task syz-executor.0:9894 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27864 9894 8437 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x571/0x11c0 kernel/locking/mutex.c:1078 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1093 nbd_start_device_ioctl drivers/block/nbd.c:1278 [inline] __nbd_ioctl drivers/block/nbd.c:1347 [inline] nbd_ioctl+0x2d6/0xb30 drivers/block/nbd.c:1387 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007f0856e6f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000007 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffcd004964f R14: 00007f0856e6f300 R15: 0000000000022000 INFO: task syz-executor.0:9957 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29216 9957 8437 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 blk_mq_freeze_queue_wait+0x105/0x220 block/blk-mq.c:152 blk_freeze_queue+0x3d/0x60 block/blk-mq.c:181 blk_mq_freeze_queue+0x9/0x10 block/blk-mq.c:190 nbd_add_socket+0x109/0x840 drivers/block/nbd.c:973 __nbd_ioctl drivers/block/nbd.c:1320 [inline] nbd_ioctl+0x4fd/0xb30 drivers/block/nbd.c:1387 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007f0856e2d188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c0b0 RCX: 0000000000465b09 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0b0 R13: 00007ffcd004964f R14: 00007f0856e2d300 R15: 0000000000022000 INFO: task syz-executor.0:9959 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29176 9959 8437 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x571/0x11c0 kernel/locking/mutex.c:1078 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1093 nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007f0856e0c188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c158 RCX: 0000000000465b09 RDX: 0000000000000401 RSI: 000000000000ab09 RDI: 0000000000000006 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c158 R13: 00007ffcd004964f R14: 00007f0856e0c300 R15: 0000000000022000 INFO: task syz-executor.0:9960 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29496 9960 8437 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x571/0x11c0 kernel/locking/mutex.c:1078 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1093 nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007f0856deb188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c200 RCX: 0000000000465b09 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000007 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c200 R13: 00007ffcd004964f R14: 00007f0856deb300 R15: 0000000000022000 INFO: task syz-executor.0:9961 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29496 9961 8437 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x571/0x11c0 kernel/locking/mutex.c:1078 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1093 nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007f0856dca188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c2a8 RCX: 0000000000465b09 RDX: 0000240000000000 RSI: 000000000000ab07 RDI: 0000000000000008 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c2a8 R13: 00007ffcd004964f R14: 00007f0856dca300 R15: 0000000000022000 INFO: task syz-executor.5:9927 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28120 9927 8436 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x571/0x11c0 kernel/locking/mutex.c:1078 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1093 nbd_start_device_ioctl drivers/block/nbd.c:1278 [inline] __nbd_ioctl drivers/block/nbd.c:1347 [inline] nbd_ioctl+0x2d6/0xb30 drivers/block/nbd.c:1387 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007f8e9d18c188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000007 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff6f87becf R14: 00007f8e9d18c300 R15: 0000000000022000 INFO: task syz-executor.5:9962 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28168 9962 8436 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 blk_mq_freeze_queue_wait+0x105/0x220 block/blk-mq.c:152 blk_freeze_queue+0x3d/0x60 block/blk-mq.c:181 blk_mq_freeze_queue+0x9/0x10 block/blk-mq.c:190 nbd_add_socket+0x109/0x840 drivers/block/nbd.c:973 __nbd_ioctl drivers/block/nbd.c:1320 [inline] nbd_ioctl+0x4fd/0xb30 drivers/block/nbd.c:1387 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007f8e9d14a188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c0b0 RCX: 0000000000465b09 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0b0 R13: 00007fff6f87becf R14: 00007f8e9d14a300 R15: 0000000000022000 INFO: task syz-executor.5:9966 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29208 9966 8436 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x571/0x11c0 kernel/locking/mutex.c:1078 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1093 nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007f8e9d108188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c200 RCX: 0000000000465b09 RDX: 0000240000000000 RSI: 000000000000ab07 RDI: 0000000000000008 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c200 R13: 00007fff6f87becf R14: 00007f8e9d108300 R15: 0000000000022000 INFO: task syz-executor.4:9929 blocked for more than 140 seconds. Not tainted 4.19.208-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28248 9929 8435 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x571/0x11c0 kernel/locking/mutex.c:1078 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1093 nbd_start_device_ioctl drivers/block/nbd.c:1278 [inline] __nbd_ioctl drivers/block/nbd.c:1347 [inline] nbd_ioctl+0x2d6/0xb30 drivers/block/nbd.c:1387 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x7ea/0x1790 block/ioctl.c:601 block_ioctl+0xd7/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: 00 e9 30 ff ff ff 83 f9 77 75 26 48 83 b8 d8 00 00 00 00 7c e2 83 f9 72 75 10 80 78 19 00 74 0a b9 03 00 00 00 e9 0c ff ff ff <31> c9 e9 05 ff ff ff 83 f9 72 eb e2 e8 c6 35 00 00 e9 c1 fe ff ff RSP: 002b:00007fe95d5b7188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000007 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffd5ca6c8af R14: 00007fe95d5b7300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1571: #0: 00000000777e606a (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4443 1 lock held by syz-executor.2/9853: #0: 000000003264fbb3 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.0/9894: #0: 0000000087798677 (&nbd->config_lock){+.+.}, at: nbd_start_device_ioctl drivers/block/nbd.c:1278 [inline] #0: 0000000087798677 (&nbd->config_lock){+.+.}, at: __nbd_ioctl drivers/block/nbd.c:1347 [inline] #0: 0000000087798677 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x2d6/0xb30 drivers/block/nbd.c:1387 1 lock held by syz-executor.0/9957: #0: 0000000087798677 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.0/9959: #0: 0000000087798677 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.0/9960: #0: 0000000087798677 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.0/9961: #0: 0000000087798677 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.5/9927: #0: 000000005c3e7ec3 (&nbd->config_lock){+.+.}, at: nbd_start_device_ioctl drivers/block/nbd.c:1278 [inline] #0: 000000005c3e7ec3 (&nbd->config_lock){+.+.}, at: __nbd_ioctl drivers/block/nbd.c:1347 [inline] #0: 000000005c3e7ec3 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x2d6/0xb30 drivers/block/nbd.c:1387 1 lock held by syz-executor.5/9962: #0: 000000005c3e7ec3 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.5/9966: #0: 000000005c3e7ec3 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.4/9929: #0: 000000006006e02d (&nbd->config_lock){+.+.}, at: nbd_start_device_ioctl drivers/block/nbd.c:1278 [inline] #0: 000000006006e02d (&nbd->config_lock){+.+.}, at: __nbd_ioctl drivers/block/nbd.c:1347 [inline] #0: 000000006006e02d (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x2d6/0xb30 drivers/block/nbd.c:1387 1 lock held by syz-executor.4/9963: #0: 000000006006e02d (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.3/9936: #0: 0000000000994c66 (&nbd->config_lock){+.+.}, at: nbd_start_device_ioctl drivers/block/nbd.c:1278 [inline] #0: 0000000000994c66 (&nbd->config_lock){+.+.}, at: __nbd_ioctl drivers/block/nbd.c:1347 [inline] #0: 0000000000994c66 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x2d6/0xb30 drivers/block/nbd.c:1387 1 lock held by syz-executor.3/9964: #0: 0000000000994c66 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.3/9968: #0: 0000000000994c66 (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.1/9952: #0: 000000002414f00f (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.1/9955: #0: 000000002414f00f (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.1/9956: #0: 000000002414f00f (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.1/9958: #0: 000000002414f00f (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.1/9970: #0: 000000002414f00f (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.1/9971: #0: 000000002414f00f (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.1/9972: #0: 000000002414f00f (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 1 lock held by syz-executor.1/9973: #0: 000000002414f00f (&nbd->config_lock){+.+.}, at: nbd_ioctl+0x12a/0xb30 drivers/block/nbd.c:1380 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1571 Comm: khungtaskd Not tainted 4.19.208-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x17c/0x226 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf6/0x120 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x5c3/0xb40 kernel/hung_task.c:287 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9189 Comm: kworker/u4:6 Not tainted 4.19.208-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_release kernel/locking/lockdep.c:3686 [inline] RIP: 0010:lock_release+0x2bf/0x840 kernel/locking/lockdep.c:3927 Code: f6 03 00 00 48 8d 78 22 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 0c 11 48 89 fa 83 e2 07 83 c2 01 38 ca 7c 08 <84> c9 0f 85 92 04 00 00 66 f7 40 22 f0 ff 74 37 48 8d 78 20 48 ba RSP: 0018:ffff8880a4b6fc60 EFLAGS: 00000006 RAX: ffff888090ddcc58 RBX: 1ffff1101496df8f RCX: 0000000000000000 RDX: 0000000000000003 RSI: ffff8880a4b6fc98 RDI: ffff888090ddcc7a RBP: ffff8880a4b6fd00 R08: 0000000000000000 R09: ffffed101746455a R10: ffffed101746455a R11: ffff8880ba322ad3 R12: ffffffff8997e780 R13: 0000000000000003 R14: ffff888090ddcc00 R15: ffff888090ddc380 FS: 0000000000000000(0000) GS:ffff8880ba300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc88d185000 CR3: 00000000aa5c2000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:247 [inline] rcu_read_unlock include/linux/rcupdate.h:681 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:423 [inline] batadv_nc_worker+0x191/0x630 net/batman-adv/network-coding.c:730 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2153 worker_thread+0x85/0xb60 kernel/workqueue.c:2296 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 ---------------- Code disassembly (best guess): 0: f6 03 00 testb $0x0,(%rbx) 3: 00 48 8d add %cl,-0x73(%rax) 6: 78 22 js 0x2a 8: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx f: fc ff df 12: 48 89 f9 mov %rdi,%rcx 15: 48 c1 e9 03 shr $0x3,%rcx 19: 0f b6 0c 11 movzbl (%rcx,%rdx,1),%ecx 1d: 48 89 fa mov %rdi,%rdx 20: 83 e2 07 and $0x7,%edx 23: 83 c2 01 add $0x1,%edx 26: 38 ca cmp %cl,%dl 28: 7c 08 jl 0x32 * 2a: 84 c9 test %cl,%cl <-- trapping instruction 2c: 0f 85 92 04 00 00 jne 0x4c4 32: 66 f7 40 22 f0 ff testw $0xfff0,0x22(%rax) 38: 74 37 je 0x71 3a: 48 8d 78 20 lea 0x20(%rax),%rdi 3e: 48 rex.W 3f: ba .byte 0xba