INFO: task syz-executor.1:29002 blocked for more than 143 seconds. Not tainted 5.15.152-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:21408 pid:29002 ppid: 28036 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 __writeback_inodes_sb_nr+0x2ce/0x370 fs/fs-writeback.c:2684 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2732 ext4_nonda_switch fs/ext4/inode.c:2933 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 ext4_file_write_iter+0x87c/0x1990 __kernel_write+0x5b1/0xa60 fs/read_write.c:539 __dump_emit+0x264/0x3a0 fs/coredump.c:875 dump_user_range+0x91/0x320 fs/coredump.c:949 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285 do_coredump+0x1852/0x31e0 fs/coredump.c:826 get_signal+0xc06/0x14e0 kernel/signal.c:2875 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 irqentry_exit_to_user_mode+0x5/0x40 kernel/entry/common.c:314 exc_page_fault+0x342/0x740 arch/x86/mm/fault.c:1544 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x3e63b6613c33 RSP: 002b:0000000020000138 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007ff5df216f80 RCX: 00007ff5df0e8da9 RDX: 0000000020000000 RSI: 0000000020000130 RDI: 0000000001004400 RBP: 00007ff5df13547a R08: 00000000200001c0 R09: 00000000200001c0 R10: 0000000020000180 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007ff5df216f80 R15: 00007ffd62844ae8 INFO: task syz-executor.0:29019 blocked for more than 144 seconds. Not tainted 5.15.152-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:21112 pid:29019 ppid: 27925 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 __writeback_inodes_sb_nr+0x2ce/0x370 fs/fs-writeback.c:2684 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2732 ext4_nonda_switch fs/ext4/inode.c:2933 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 ext4_file_write_iter+0x87c/0x1990 __kernel_write+0x5b1/0xa60 fs/read_write.c:539 __dump_emit+0x264/0x3a0 fs/coredump.c:875 dump_user_range+0x91/0x320 fs/coredump.c:949 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285 do_coredump+0x1852/0x31e0 fs/coredump.c:826 get_signal+0xc06/0x14e0 kernel/signal.c:2875 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 irqentry_exit_to_user_mode+0x5/0x40 kernel/entry/common.c:314 exc_page_fault+0x342/0x740 arch/x86/mm/fault.c:1544 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x8bacb38df9 RSP: 002b:0000000020000148 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f9f55075f80 RCX: 00007f9f54f47da9 RDX: 0000000020000000 RSI: 0000000020000140 RDI: 0000000001004400 RBP: 00007f9f54f9447a R08: 00000000200001c0 R09: 00000000200001c0 R10: 0000000020000180 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007f9f55075f80 R15: 00007ffe9315a268 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c91f720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:3/553: 2 locks held by getty/3256: #0: ffff88802492d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002bab2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 2 locks held by kworker/1:4/3522: #0: ffff888011c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90002fd7d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 4 locks held by kworker/u4:8/3780: #0: ffff888011dcd138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90004777d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8d9cfe50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:558 #3: ffffffff8c923ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #3: ffffffff8c923ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845 2 locks held by kworker/u4:9/12046: 2 locks held by syz-executor.0/28392: 4 locks held by syz-executor.0/28983: 1 lock held by syz-executor.4/28989: 3 locks held by syz-executor.1/29002: #0: ffff88814b062460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff88804074d3b0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] #1: ffff88804074d3b0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff88814b0620e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2729 3 locks held by syz-executor.0/29019: #0: ffff88814b062460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff888033b403f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] #1: ffff888033b403f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff88814b0620e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2729 2 locks held by syz-executor.4/29024: 3 locks held by syz-executor.0/29038: 3 locks held by syz-executor.4/29060: 1 lock held by syz-executor.0/29070: 1 lock held by syz-executor.4/29092: 7 locks held by syz-executor.3/29595: #0: ffff88807f0fc460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590 #1: ffff8880608f4888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:287 #2: ffff88801e7d2bd0 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:288 #3: ffffffff8d357a88 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf1/0x470 drivers/net/netdevsim/bus.c:344 #4: ffff88801d538178 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #4: ffff88801d538178 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1044 [inline] #4: ffff88801d538178 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xc2/0x7f0 drivers/base/dd.c:1259 #5: ffff888078ebb250 (&devlink->lock){+.+.}-{3:3}, at: devlink_traps_unregister+0x2d/0x250 net/core/devlink.c:11030 #6: ffffffff8c923ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #6: ffffffff8c923ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 4 locks held by syz-executor.2/29635: #0: ffff88807f0fc460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590 #1: ffff88801f334888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:287 #2: ffff88801e7d2bd0 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:288 #3: ffffffff8d357a88 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf1/0x470 drivers/net/netdevsim/bus.c:344 4 locks held by syz-executor.1/29648: #0: ffff88807f0fc460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590 #1: ffff88803f80d488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:287 #2: ffff88801e7d2bd0 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:288 #3: ffffffff8d357a88 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf1/0x470 drivers/net/netdevsim/bus.c:344 4 locks held by syz-executor.0/29653: #0: ffff88807f0fc460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590 #1: ffff88803d1cf488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:287 #2: ffff88801e7d2bd0 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:288 #3: ffffffff8d357a88 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf1/0x470 drivers/net/netdevsim/bus.c:344 1 lock held by syz-executor.4/29725: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5626 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 12046 Comm: kworker/u4:9 Not tainted 5.15.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work RIP: 0010:unwind_next_frame+0x143e/0x1fa0 arch/x86/kernel/unwind_orc.c:616 Code: 0f 85 78 02 00 00 c6 05 de cc 97 0c 01 48 c7 c7 c0 7e 88 8a e9 0e fa ff ff bf 01 00 00 00 e8 19 c6 1e 00 65 8b 0d 0a f4 c9 7e 01 85 c9 0f 85 a1 02 00 00 e8 93 0b c8 ff e9 97 02 00 00 80 3d RSP: 0018:ffffc9000b0875e8 EFLAGS: 00000297 RAX: 0000000080000001 RBX: ffffc9000b0876b0 RCX: 0000000080000000 RDX: dffffc0000000000 RSI: ffffc9000b087a50 RDI: 0000000000000001 RBP: ffffc9000b087a60 R08: ffffc9000b087a50 R09: ffffc9000b0876f0 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff1cc6839 R13: 1ffffffff1cc6839 R14: ffffc9000b080000 R15: ffffc9000b0876a0 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff802c0108 CR3: 000000000c68e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kmem_cache_free+0x91/0x1f0 mm/slub.c:3515 ext4_end_io_end fs/ext4/page-io.c:194 [inline] ext4_do_flush_completed_IO fs/ext4/page-io.c:259 [inline] ext4_end_io_rsv_work+0x5d6/0x6e0 fs/ext4/page-io.c:273 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298