INFO: task syz.2.576:10659 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.576 state:D stack:27424 pid:10659 tgid:10653 ppid:9995 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:850 [inline] do_rmdir+0x263/0x580 fs/namei.c:4387 __do_sys_rmdir fs/namei.c:4418 [inline] __se_sys_rmdir fs/namei.c:4416 [inline] __x64_sys_rmdir+0x47/0x50 fs/namei.c:4416 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc90577dff9 RSP: 002b:00007fc9051ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000054 RAX: ffffffffffffffda RBX: 00007fc905936058 RCX: 00007fc90577dff9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040 RBP: 00007fc9057f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fc905936058 R15: 00007ffefac71ed8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 4 locks held by kworker/u8:6/1905: 3 locks held by kworker/u8:8/2980: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90009dcfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90009dcfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 3 locks held by kworker/u8:9/3814: 3 locks held by kworker/u8:10/3852: #0: ffff88814beda948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814beda948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc9000a88fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000a88fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 1 lock held by dhcpcd/4890: #0: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1aa0 net/ipv4/devinet.c:1097 2 locks held by getty/4973: #0: ffff88814c1740a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:7/9371: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90002d2fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90002d2fd00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by syz.2.576/10654: 2 locks held by syz.2.576/10659: #0: ffff888057d62420 (sb_writers#33){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88805ea38180 (&type->i_mutex_dir_key#23/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline] #1: ffff88805ea38180 (&type->i_mutex_dir_key#23/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387 1 lock held by syz.4.655/11448: 1 lock held by syz.4.655/11450: 1 lock held by syz.4.655/11451: #0: ffff888044c64180 (&type->i_mutex_dir_key#23/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline] #0: ffff888044c64180 (&type->i_mutex_dir_key#23/1){+.+.}-{3:3}, at: filename_create+0x260/0x540 fs/namei.c:4026 1 lock held by syz.4.655/11452: #0: ffff888044c64180 (&type->i_mutex_dir_key#23){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:825 [inline] #0: ffff888044c64180 (&type->i_mutex_dir_key#23){.+.+}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1748 1 lock held by syz.4.655/11453: #0: ffff888044c64180 (&type->i_mutex_dir_key#23){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:825 [inline] #0: ffff888044c64180 (&type->i_mutex_dir_key#23){.+.+}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1748 2 locks held by syz.4.655/11454: #0: ffff88806cb86420 (sb_writers#33){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff888044c64180 (&type->i_mutex_dir_key#23/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline] #1: ffff888044c64180 (&type->i_mutex_dir_key#23/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387 1 lock held by syz-executor/11760: #0: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 7 locks held by syz-executor/11899: #0: ffff888032f0e420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff888032f0e420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 #1: ffff888028782888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff888143fb4698 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55d2a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88805210e0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88805210e0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88805210e0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff888076803250 (&devlink->lock_key#49){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773 1 lock held by syz-executor/11970: #0: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/12054: #0: ffffffff8fcbf208 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x48c/0x2400 drivers/net/tun.c:3121 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10654 Comm: syz.2.576 Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217 Code: 80 d7 03 00 65 8b 15 10 fc 6e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc RSP: 0018:ffffc9000976f100 EFLAGS: 00000246 RAX: ffffffff81cced31 RBX: 0000000000000002 RCX: ffff888025798000 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff81cced14 R09: 1ffffd40003e56ee R10: dffffc0000000000 R11: fffff940003e56ef R12: 0000000000000002 R13: dffffc0000000000 R14: ffffffff81ccebce R15: ffffea0001f2b774 FS: 00007fc9064996c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f94033052d8 CR3: 0000000028cac000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:107 [inline] raw_atomic_try_cmpxchg include/linux/atomic/atomic-arch-fallback.h:2130 [inline] raw_atomic_fetch_add_unless include/linux/atomic/atomic-arch-fallback.h:2431 [inline] raw_atomic_add_unless include/linux/atomic/atomic-arch-fallback.h:2456 [inline] atomic_add_unless include/linux/atomic/atomic-instrumented.h:1518 [inline] page_ref_add_unless include/linux/page_ref.h:238 [inline] folio_ref_add_unless include/linux/page_ref.h:248 [inline] folio_try_get+0x181/0x350 include/linux/page_ref.h:264 filemap_get_entry+0x240/0x3b0 mm/filemap.c:1852 __filemap_get_folio+0x71/0xbd0 mm/filemap.c:1887 grow_dev_folio fs/buffer.c:1043 [inline] grow_buffers fs/buffer.c:1109 [inline] __getblk_slow fs/buffer.c:1135 [inline] bdev_getblk+0x1d8/0x550 fs/buffer.c:1437 __bread_gfp+0x86/0x400 fs/buffer.c:1491 sb_bread include/linux/buffer_head.h:346 [inline] get_branch+0x2c3/0x6e0 fs/sysv/itree.c:102 get_block+0x180/0x16d0 fs/sysv/itree.c:222 block_read_full_folio+0x418/0xcd0 fs/buffer.c:2401 filemap_read_folio+0x14b/0x630 mm/filemap.c:2367 do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3825 read_mapping_folio include/linux/pagemap.h:1011 [inline] dir_get_folio fs/sysv/dir.c:64 [inline] sysv_find_entry+0x16a/0x4b0 fs/sysv/dir.c:154 sysv_inode_by_name+0x98/0x2a0 fs/sysv/dir.c:370 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38 __lookup_slow+0x28c/0x3f0 fs/namei.c:1732 lookup_slow+0x53/0x70 fs/namei.c:1749 walk_component+0x2e1/0x410 fs/namei.c:2053 lookup_last fs/namei.c:2556 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2580 filename_lookup+0x256/0x610 fs/namei.c:2609 do_readlinkat+0xf0/0x3a0 fs/stat.c:537 __do_sys_readlink fs/stat.c:574 [inline] __se_sys_readlink fs/stat.c:571 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:571 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc90577dff9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc906499038 EFLAGS: 00000246 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00007fc905935f80 RCX: 00007fc90577dff9 RDX: 00000000000000e9 RSI: 0000000020000b00 RDI: 0000000020000700 RBP: 00007fc9057f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc905935f80 R15: 00007ffefac71ed8