INFO: task syz-executor298:5873 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-executor298 state:D stack:26920 pid:5873 tgid:5873 ppid:5872 task_flags:0x40004c flags:0x00004002 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 __do_sys_exit_group kernel/exit.c:1111 [inline] __se_sys_exit_group kernel/exit.c:1109 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1109 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 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: 0033:0x7f46354c9389 RSP: 002b:00007ffd7521a648 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f46354c9389 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 00007f46355552b0 R08: ffffffffffffffb0 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007f46355552b0 R13: 0000000000000000 R14: 00007f4635555e40 R15: 00007f46354971a0 Showing all locks held in the system: 2 locks held by ksoftirqd/0/15: #0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636 #1: ffff8880b8624008 (per_cpu_ptr(&psi_seq, cpu)){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:937 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/5609: #0: ffff88814d1fd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor298/5873: #0: ffff8880217fd7e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:412 [inline] #0: ffff8880217fd7e0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 2 locks held by syz-executor298/5874: ============================================= NMI backtrace for cpu 1 CPU: 1 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 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: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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5874 Comm: syz-executor298 Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:118 [inline] RIP: 0010:lock_acquire+0x94/0x360 kernel/locking/lockdep.c:5847 Code: 0f 84 d7 01 00 00 83 3d 19 4d 46 0e 00 0f 84 f0 00 00 00 48 8b b4 24 90 00 00 00 4c 89 ef e8 83 73 85 00 83 3d fc 4c 46 0e 00 <0f> 84 fa 00 00 00 65 8b 05 af dc 49 11 85 c0 0f 85 eb 00 00 00 65 RSP: 0018:ffffc90004217138 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: cdfdc9e4b60aee00 RDX: 0000000000000000 RSI: ffffffff817301b2 RDI: 1ffffffff1ca7b14 RBP: ffffffff81730195 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc900042172f8 R11: ffffffff81ac9660 R12: 0000000000000002 R13: ffffffff8e53d8a0 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f46354846c0(0000) GS:ffff8881257ab000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffed0fff19 CR3: 0000000075b22000 CR4: 00000000003526f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4396 kmalloc_noprof include/linux/slab.h:905 [inline] slab_free_hook mm/slub.c:2369 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x166/0x400 mm/slub.c:4782 remove_vma mm/vma.c:468 [inline] vms_complete_munmap_vmas+0x626/0x8a0 mm/vma.c:1293 do_vmi_align_munmap+0x358/0x420 mm/vma.c:1536 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1584 do_munmap+0xe1/0x140 mm/mmap.c:1068 mremap_to+0x2df/0x7a0 mm/mremap.c:1368 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: 0033:0x7f46354cb329 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4635484228 EFLAGS: 00000246 ORIG_RAX: 0000000000000019 RAX: ffffffffffffffda RBX: 00007f4635555308 RCX: 00007f46354cb329 RDX: 0000000000600002 RSI: 0000000000600002 RDI: 0000200000000000 RBP: 00007f4635555300 R08: 0000200000a00000 R09: 00007f46354846c0 R10: 0000000000000007 R11: 0000000000000246 R12: 00007f463555530c R13: 0000200000000000 R14: 0000200000000140 R15: 00007ffd7521a5c8 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.319 msecs