INFO: task syz.7.764:11163 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00085-gc94d59a126cb #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.764 state:D stack:23576 pid:11163 tgid:11162 ppid:7870 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 percpu_rwsem_wait+0x2ab/0x300 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xe3/0x120 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:66 [inline] __sb_start_write include/linux/fs.h:1783 [inline] sb_start_write+0x185/0x1c0 include/linux/fs.h:1919 mnt_want_write+0x41/0x90 fs/namespace.c:556 open_last_lookups fs/namei.c:3789 [inline] path_openat+0x85d/0x3830 fs/namei.c:4036 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_open fs/open.c:1452 [inline] __se_sys_open fs/open.c:1448 [inline] __x64_sys_open+0x11e/0x150 fs/open.c:1448 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f970ef8e969 RSP: 002b:00007f970feb4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f970f1b5fa0 RCX: 00007f970ef8e969 RDX: 0000000000000000 RSI: 000000000014927e RDI: 0000200000000180 RBP: 00007f970f010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f970f1b5fa0 R15: 00007ffff2822128 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff88801f68b148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f68b148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 #2: ffff88802483a8e0 (&lo->lo_work_lock){..-.}-{3:3}, at: spin_lock_irq include/linux/spinlock.h:376 [inline] #2: ffff88802483a8e0 (&lo->lo_work_lock){..-.}-{3:3}, at: loop_process_work+0xb12/0xf30 drivers/block/loop.c:1927 1 lock held by khungtaskd/31: #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/u8:4/63: 2 locks held by kworker/u8:10/3478: 1 lock held by udevd/5192: 2 locks held by getty/5585: #0: ffff888034df10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/5820: #0: ffff888148db4120 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #0: ffff888148db4120 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_read_iter+0x2f8/0x440 block/fops.c:808 1 lock held by syz.7.764/11163: #0: ffff88807de0e420 (sb_writers#34){++++}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 1 lock held by syz.0.1002/13906: 2 locks held by syz.8.1032/13912: 3 locks held by sed/13924: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00085-gc94d59a126cb #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5838 Comm: udevd Not tainted 6.15.0-rc6-syzkaller-00085-gc94d59a126cb #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x8/0x90 kernel/kcov.c:321 Code: 48 89 44 11 20 e9 98 11 92 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 50 72 92 65 8b 15 38 5a b2 10 81 e2 00 01 ff 00 RSP: 0018:ffffc9000444f4d8 EFLAGS: 00000246 RAX: ffffffff8b47ffd2 RBX: 0000000000000002 RCX: 0000000000000000 RDX: ffff88805ef8da00 RSI: 00007fa6aa3fffff RDI: 0000000000000000 RBP: ffffc9000444f6b0 R08: ffff88805ef8da00 R09: 0000000000000004 R10: 0000000000000003 R11: 0000000000000000 R12: ffff888032f3fc18 R13: 00007fa6aa3fffff R14: 00007fa6aa3f2fff R15: ffff888032f3fc18 FS: 00007fa6aaab2880(0000) GS:ffff8881261fb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa6aaa42000 CR3: 000000006b388000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mas_validate_limits lib/maple_tree.c:7441 [inline] mt_validate+0xbe2/0x4380 lib/maple_tree.c:7561 validate_mm+0xb6/0x4b0 mm/vma.c:595 mmap_region+0x18b5/0x1e50 mm/vma.c:2603 do_mmap+0xc68/0x1100 mm/mmap.c:561 vm_mmap_pgoff+0x31b/0x4c0 mm/util.c:579 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa6aa31d822 Code: 00 00 00 0f 1f 44 00 00 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 3b 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 76 5b 5d c3 0f 1f 00 48 8b 05 a1 35 0d 00 64 RSP: 002b:00007ffdbf618348 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa6aa31d822 RDX: 0000000000000003 RSI: 0000000000000200 RDI: 0000000000000000 RBP: 0000000000000022 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000f89200 R14: 0000562e36758100 R15: 0000000000f84200