INFO: task syz-executor:4259 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:23024 pid:4259 ppid:4258 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x161/0x7b0 fs/ext4/inode.c:6129 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6166 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6284 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 wp_page_shared+0x167/0x370 mm/memory.c:3358 handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x1b1b/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f471747c6e2 RSP: 002b:00007fff504f5a40 EFLAGS: 00010202 RAX: 00007f4715330000 RBX: 0000555583524ca0 RCX: 0000000000000007 RDX: 000000000000336a RSI: 00005555835299b8 RDI: 0000000000000080 RBP: 00007fff504f5f40 R08: 0000555583529ae0 R09: 000000000000008d R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff504f5d80 R13: 00007fff504f5b70 R14: 585858582e7a7973 R15: 00007fff504f5ac0 INFO: task syz.2.1170:7511 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1170 state:D stack:27632 pid:7511 ppid:4276 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x161/0x7b0 fs/ext4/inode.c:6129 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6166 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6284 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 do_shared_fault mm/memory.c:4694 [inline] do_fault mm/memory.c:4762 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7fbe2ec6baa3 RSP: 002b:00007ffc9ea98620 EFLAGS: 00010246 RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000001b2f864000 RDX: 0000001b2f824000 RSI: 0000000000400000 RDI: 00007fbe2efe0708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffc9ea988b0 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2e170 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2e990 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8cb2d7e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d7e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d7e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6529 6 locks held by kworker/u4:4/54: #0: ffff888141a7f938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #1: ffffc90000bf7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #2: ffff88807dd380e0 (&type->s_umount_key#31){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:415 #3: ffff88807dd3ac18 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717 #4: ffff88807dd3c990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 #5: ffff88807203beb8 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x914/0x1a90 fs/ext4/inode.c:674 2 locks held by getty/4027: #0: ffff88802ed9e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198 3 locks held by syz-executor/4259: #0: ffff88807d10cc58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807d10cc58 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline] #0: ffff88807d10cc58 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382 #1: ffff88807dd38558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline] #1: ffff88807dd38558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline] #1: ffff88807dd38558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6283 #2: ffff88807dd3c990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 3 locks held by syz.2.1170/7511: #0: ffff88801d3dea58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88801d3dea58 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline] #0: ffff88801d3dea58 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382 #1: ffff88807dd38558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline] #1: ffff88807dd38558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline] #1: ffff88807dd38558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6283 #2: ffff88807dd3c990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf0e/0xf50 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3621 Comm: syslogd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:match_held_lock+0x0/0xb0 kernel/locking/lockdep.c:5121 Code: 03 00 75 cf 48 c7 c7 40 17 8c 8a 48 c7 c6 80 17 8c 8a e8 43 2c 1b f7 0f 0b eb b6 e8 ca fa ff ff 66 2e 0f 1f 84 00 00 00 00 00 01 00 00 00 48 39 77 10 74 6c 53 81 7f 20 00 00 10 00 72 5f 48 RSP: 0018:ffffc900001e06b8 EFLAGS: 00000083 RAX: 0000000000000002 RBX: ffff88807c945a00 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffff8880b8f3acd8 RDI: ffff88807c946508 RBP: 00000000ffffffff R08: 0000000000000001 R09: ffff88801cac4ee8 R10: ffffffff8fa24050 R11: ffffffff8fa24043 R12: 0000000000000001 R13: 0000000000000046 R14: ffff8880b8f3acd8 R15: ffff88807c946508 FS: 00007f381ef8ac80(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056107c577168 CR3: 000000007e079000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held kernel/locking/lockdep.c:5419 [inline] lock_is_held_type+0xa6/0x190 kernel/locking/lockdep.c:5721 lock_is_held include/linux/lockdep.h:283 [inline] lockdep_assert_rq_held kernel/sched/sched.h:1353 [inline] psi_group_change+0xe3/0x13b0 kernel/sched/psi.c:789 psi_task_change+0xdc/0x240 kernel/sched/psi.c:924 psi_enqueue kernel/sched/stats.h:143 [inline] enqueue_task+0x23b/0x280 kernel/sched/core.c:2056 activate_task+0x3d/0xa0 kernel/sched/core.c:2088 attach_task+0xf0/0x190 kernel/sched/fair.c:8597 attach_tasks kernel/sched/fair.c:8632 [inline] load_balance+0x3c89/0x4ef0 kernel/sched/fair.c:10619 rebalance_domains+0x459/0x9d0 kernel/sched/fair.c:11024 handle_softirqs+0x291/0x910 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:finish_task_switch+0x267/0x8e0 kernel/sched/core.c:5125 Code: d9 08 85 c0 0f 84 38 01 00 00 48 85 db 0f 85 57 01 00 00 0f 1f 44 00 00 4c 89 e7 e8 93 20 e3 08 e8 1e 18 2f 00 fb 4c 8b 65 b8 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 RSP: 0018:ffffc900032c7600 EFLAGS: 00000286 RAX: 298d8098383a6800 RBX: 0000000000000000 RCX: 298d8098383a6800 RDX: dffffc0000000000 RSI: ffffffff8a8c18a0 RDI: ffffffff8adf68a0 RBP: ffffc900032c7650 R08: ffff8880b8f3acc3 R09: 1ffff110171e7598 R10: dffffc0000000000 R11: ffffed10171e7599 R12: ffff88807c945a00 R13: 1ffff110171e76f2 R14: dffffc0000000000 R15: ffff8880b8f3b790 context_switch kernel/sched/core.c:5249 [inline] __schedule+0x1087/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144 __skb_wait_for_more_packets+0x3a8/0x590 net/core/datagram.c:120 __unix_dgram_recvmsg+0x2a1/0xda0 net/unix/af_unix.c:2466 sock_recvmsg_nosec net/socket.c:1023 [inline] sock_recvmsg net/socket.c:1041 [inline] sock_read_iter+0x2da/0x3a0 net/socket.c:1122 call_read_iter include/linux/fs.h:2265 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x471/0x960 fs/read_write.c:470 ksys_read+0x14d/0x260 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f381f0da407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007fff8f0de230 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f381ef8ac80 RCX: 00007f381f0da407 RDX: 00000000000000ff RSI: 0000564e43bc7950 RDI: 0000000000000000 RBP: 0000564e43bc7910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000564e43bc79a0 R13: 0000000000000000 R14: 0000564e43bc7950 R15: 0000564e16b0bd98