INFO: task syz.2.894:9179 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.894 state:D stack:25096 pid:9179 tgid:9179 ppid:5849 task_flags:0x40044c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088 __down_read_common kernel/locking/rwsem.c:1263 [inline] __down_read kernel/locking/rwsem.c:1276 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541 mmap_read_lock include/linux/mmap_lock.h:412 [inline] exit_mm+0xcc/0x2c0 kernel/exit.c:557 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:40 [inline] exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:73 exc_page_fault+0x9f/0xf0 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f82e5d463f6 RSP: 002b:00007ffe70693fd0 EFLAGS: 00010246 RAX: 00007f82e3b94000 RBX: 00007f82e3bb46c0 RCX: 00007f82e5d8ea67 RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007f82e3bb46c0 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000021000 R11: 0000000000000206 R12: 00007ffe70694120 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 INFO: task syz.2.894:9181 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.894 state:D stack:24200 pid:9181 tgid:9179 ppid:5849 task_flags:0x40054c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088 __down_read_common kernel/locking/rwsem.c:1263 [inline] __down_read kernel/locking/rwsem.c:1276 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541 mmap_read_lock include/linux/mmap_lock.h:412 [inline] exit_mm+0xcc/0x2c0 kernel/exit.c:557 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f82e5d8e9a9 RSP: 002b:00007f82e3bd50e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f82e5fb6088 RCX: 00007f82e5d8e9a9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f82e5fb6088 RBP: 00007f82e5fb6080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82e5fb608c R13: 0000000000000000 R14: 00007ffe70693f40 R15: 00007ffe70694028 Showing all locks held in the system: 2 locks held by ksoftirqd/1/23: 1 lock held by khungtaskd/31: #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by getty/5605: #0: ffff88814d3470a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz.2.894/9179: #0: ffff88804e65e2a0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:412 [inline] #0: ffff88804e65e2a0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.2.894/9180: 1 lock held by syz.2.894/9181: #0: ffff88804e65e2a0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:412 [inline] #0: ffff88804e65e2a0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 6 locks held by syz.1.1901/13746: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 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: 9180 Comm: syz.2.894 Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:104 [inline] RIP: 0010:__up_read+0x287/0x680 kernel/locking/rwsem.c:1367 Code: 00 0f 84 87 00 00 00 e8 57 c6 2d 03 49 81 e4 03 ff ff ff 49 83 fc 02 74 5c bf 01 00 00 00 e8 f0 0f f3 ff 65 8b 05 59 0c 4a 11 <85> c0 74 59 48 c7 44 24 20 0e 36 e0 45 48 b8 00 00 00 00 00 fc ff RSP: 0018:ffffc900035373a0 EFLAGS: 00000297 RAX: 0000000080000000 RBX: ffff88802f5eb998 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000008 RDI: 00000000ffffffff RBP: ffffc90003537450 R08: ffff88802f5eb99f R09: 1ffff11005ebd733 R10: dffffc0000000000 R11: ffffed1005ebd734 R12: 0000000000000000 R13: 1ffff11005ebd734 R14: ffff888026529e00 R15: ffff88802f5eb9a0 FS: 00007f82e3bf66c0(0000) GS:ffff8881258ab000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff2fdf83178 CR3: 000000007c574000 CR4: 00000000003526f0 Call Trace: anon_vma_unlock_read include/linux/rmap.h:147 [inline] validate_mm+0x24e/0x4b0 mm/vma.c:682 vma_link+0x366/0x450 mm/vma.c:1799 copy_vma+0x70c/0x940 mm/vma.c:1880 copy_vma_and_data mm/mremap.c:1184 [inline] move_vma+0x81f/0x1840 mm/mremap.c:1282 mremap_to+0x6d6/0x7a0 mm/mremap.c:1406 remap_move mm/mremap.c:1863 [inline] do_mremap mm/mremap.c:1906 [inline] __do_sys_mremap mm/mremap.c:1970 [inline] __se_sys_mremap+0xa0b/0xef0 mm/mremap.c:1938 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f82e5d8e9a9 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:00007f82e3bf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000019 RAX: ffffffffffffffda RBX: 00007f82e5fb5fa0 RCX: 00007f82e5d8e9a9 RDX: 0000000000600002 RSI: 0000000000600002 RDI: 0000200000000000 RBP: 00007f82e5e10d69 R08: 0000200000a00000 R09: 0000000000000000 R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f82e5fb5fa0 R15: 00007ffe70694028