INFO: task jbd2/sda1-8:5163 blocked for more than 143 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jbd2/sda1-8 state:D stack:26008 pid:5163 tgid:5163 ppid:2 task_flags:0x240040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 jbd2_journal_wait_updates+0x11e/0x240 fs/jbd2/transaction.c:843 jbd2_journal_commit_transaction+0x828/0x6830 fs/jbd2/commit.c:454 kjournald2+0x1f4/0x760 fs/jbd2/journal.c:201 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz-executor:5817 blocked for more than 143 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:23112 pid:5817 tgid:5817 ppid:5815 task_flags:0x400100 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 wait_transaction_locked+0x1a1/0x230 fs/jbd2/transaction.c:152 add_transaction_credits+0x110/0xe60 fs/jbd2/transaction.c:222 start_this_handle+0x3e7/0x1410 fs/jbd2/transaction.c:403 jbd2__journal_start+0x394/0x6a0 fs/jbd2/transaction.c:501 __ext4_journal_start_sb+0x195/0x690 fs/ext4/ext4_jbd2.c:114 __ext4_journal_start fs/ext4/ext4_jbd2.h:242 [inline] ext4_dirty_inode+0xa1/0x130 fs/ext4/inode.c:6100 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 wp_page_shared mm/memory.c:3688 [inline] do_wp_page+0xb9e/0x58e0 mm/memory.c:3907 handle_pte_fault mm/memory.c:6013 [inline] __handle_mm_fault+0x1ada/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fac4b077dcf RSP: 002b:00007ffc8a1518b0 EFLAGS: 00010202 RAX: 00007fac499fc000 RBX: 00005555590360a0 RCX: 0000000000000001 RDX: 1ffffffff0f45909 RSI: 0000555559037338 RDI: 0000000000000002 RBP: 00007ffc8a151ba0 R08: 0000555559037388 R09: 0000000000000b21 R10: 0000000000000001 R11: 00007ffc8a151db0 R12: 00007ffc8a151c00 R13: 0000000000000004 R14: 00007ffc8a151920 R15: 00007ffc8a1519f0 INFO: task kworker/u8:4:20647 blocked for more than 144 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:4 state:D stack:23512 pid:20647 tgid:20647 ppid:2 task_flags:0x4248060 flags:0x00004000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 io_schedule+0xbf/0x130 kernel/sched/core.c:7742 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:247 __wait_on_bit_lock+0x112/0x1a0 kernel/sched/wait_bit.c:90 out_of_line_wait_on_bit_lock+0xd9/0x110 kernel/sched/wait_bit.c:117 wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline] __lock_buffer+0x67/0x70 fs/buffer.c:71 lock_buffer include/linux/buffer_head.h:434 [inline] do_get_write_access+0x8cd/0x12a0 fs/jbd2/transaction.c:968 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1241 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_ext_get_access fs/ext4/extents.c:168 [inline] ext4_ext_insert_extent+0xf96/0x4610 fs/ext4/extents.c:2125 ext4_ext_map_blocks+0x205b/0x5d60 fs/ext4/extents.c:4400 ext4_map_create_blocks fs/ext4/inode.c:520 [inline] ext4_map_blocks+0x45b/0x1390 fs/ext4/inode.c:706 mpage_map_one_extent fs/ext4/inode.c:2224 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2277 [inline] ext4_do_writepages+0x1a2c/0x3490 fs/ext4/inode.c:2739 ext4_writepages+0x37a/0x7d0 fs/ext4/inode.c:2829 do_writepages+0x1b2/0x820 mm/page-writeback.c:2656 __writeback_single_inode+0x160/0xfb0 fs/fs-writeback.c:1680 writeback_sb_inodes+0x601/0xf90 fs/fs-writeback.c:1976 __writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2047 wb_writeback+0x7f3/0xb70 fs/fs-writeback.c:2158 wb_check_background_flush fs/fs-writeback.c:2228 [inline] wb_do_writeback fs/fs-writeback.c:2316 [inline] wb_workfn+0x748/0xbe0 fs/fs-writeback.c:2343 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.6.8074:23644 blocked for more than 144 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.8074 state:D stack:28472 pid:23644 tgid:23644 ppid:18731 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 wait_transaction_locked+0x1a1/0x230 fs/jbd2/transaction.c:152 add_transaction_credits+0x110/0xe60 fs/jbd2/transaction.c:222 start_this_handle+0x3e7/0x1410 fs/jbd2/transaction.c:403 jbd2__journal_start+0x394/0x6a0 fs/jbd2/transaction.c:501 __ext4_journal_start_sb+0x195/0x690 fs/ext4/ext4_jbd2.c:114 __ext4_journal_start fs/ext4/ext4_jbd2.h:242 [inline] ext4_dirty_inode+0xa1/0x130 fs/ext4/inode.c:6100 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing+0x29c/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fb41de6eada RSP: 002b:00007fffdc8afd00 EFLAGS: 00010202 RAX: 0000001b2ce20000 RBX: 00007fb41ece5720 RCX: 0000001b2ce1fff8 RDX: 00000000003ffde8 RSI: 00000000003ffde8 RDI: 00007fb41ece5700 RBP: ffffffff893aacab R08: 00007fb41e1b6038 R09: 00007fb41e1a2000 R10: 00007fb41d5ff008 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000001 R14: ffffffff893aa5c1 R15: 0000000000000001 INFO: task syz.0.8075:23646 blocked for more than 145 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.8075 state:D stack:28632 pid:23646 tgid:23646 ppid:5830 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 wait_transaction_locked+0x1a1/0x230 fs/jbd2/transaction.c:152 add_transaction_credits+0x110/0xe60 fs/jbd2/transaction.c:222 start_this_handle+0x3e7/0x1410 fs/jbd2/transaction.c:403 jbd2__journal_start+0x394/0x6a0 fs/jbd2/transaction.c:501 __ext4_journal_start_sb+0x195/0x690 fs/ext4/ext4_jbd2.c:114 __ext4_journal_start fs/ext4/ext4_jbd2.h:242 [inline] ext4_dirty_inode+0xa1/0x130 fs/ext4/inode.c:6100 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing+0x29c/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f262b86547b RSP: 002b:00007ffed23d2f10 EFLAGS: 00010246 RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b2fc20000 RSI: 0000000000400000 RDI: 00007f262ba98d50 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000927c0 R14: 00000000000958eb R15: 00007ffed23d31c0 INFO: task syz.5.8076:23647 blocked for more than 145 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.8076 state:D stack:28792 pid:23647 tgid:23647 ppid:23109 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 wait_transaction_locked+0x1a1/0x230 fs/jbd2/transaction.c:152 add_transaction_credits+0x110/0xe60 fs/jbd2/transaction.c:222 start_this_handle+0x3e7/0x1410 fs/jbd2/transaction.c:403 jbd2__journal_start+0x394/0x6a0 fs/jbd2/transaction.c:501 __ext4_journal_start_sb+0x195/0x690 fs/ext4/ext4_jbd2.c:114 __ext4_journal_start fs/ext4/ext4_jbd2.h:242 [inline] ext4_dirty_inode+0xa1/0x130 fs/ext4/inode.c:6100 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing+0x29c/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f214c66547b RSP: 002b:00007ffe69e61cd0 EFLAGS: 00010246 RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b2eb20000 RSI: 0000000000400000 RDI: 00007f214c898d50 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000927c0 R14: 0000000000095915 R15: 00007ffe69e61f80 INFO: task syz.4.8077:23648 blocked for more than 146 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.8077 state:D stack:28792 pid:23648 tgid:23648 ppid:11516 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 wait_transaction_locked+0x1a1/0x230 fs/jbd2/transaction.c:152 add_transaction_credits+0x110/0xe60 fs/jbd2/transaction.c:222 start_this_handle+0x3e7/0x1410 fs/jbd2/transaction.c:403 jbd2__journal_start+0x394/0x6a0 fs/jbd2/transaction.c:501 __ext4_journal_start_sb+0x195/0x690 fs/ext4/ext4_jbd2.c:114 __ext4_journal_start fs/ext4/ext4_jbd2.h:242 [inline] ext4_dirty_inode+0xa1/0x130 fs/ext4/inode.c:6100 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing+0x29c/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f5068e6547b RSP: 002b:00007fffe6e2cbc0 EFLAGS: 00010246 RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b31720000 RSI: 0000000000400000 RDI: 00007f5069098d50 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000927c0 R14: 0000000000095980 R15: 00007fffe6e2ce70 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 2 locks held by syz-executor/5817: #0: ffff88807fe69588 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff8880244c0518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 6 locks held by kworker/u8:4/20647: #0: ffff88801f6e6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000df97d18 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff8880244c00e0 (&type->s_umount_key#31){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:562 #3: ffff8880244c2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x1b2/0x820 mm/page-writeback.c:2656 #4: ffff8880244c4950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444 #5: ffff88807846a080 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x355/0x1390 fs/ext4/inode.c:705 2 locks held by getty/22707: #0: ffff88814ce430a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000b4f32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 2 locks held by syz.6.8074/23644: #0: ffff8880679c76c8 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff8880244c0518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 2 locks held by syz.0.8075/23646: #0: ffff888060ce1308 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff8880244c0518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 2 locks held by syz.5.8076/23647: #0: ffff88807a16d6c8 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff8880244c0518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 2 locks held by syz.4.8077/23648: #0: ffff88807f358808 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff8880244c0518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U I 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 PREEMPT(full) Tainted: [U]=USER, [I]=FIRMWARE_WORKAROUND Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/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+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245