INFO: task syz-executor:5759 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:22488 pid:5759 ppid:5758 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x5c9/0xe00 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x10c/0x140 fs/jbd2/transaction.c:1231 __ext4_journal_get_write_access+0x208/0x6d0 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x205/0x2a0 fs/ext4/inode.c:5933 __ext4_mark_inode_dirty+0x13f/0x6d0 fs/ext4/inode.c:6107 ext4_dirty_inode+0xcb/0x110 fs/ext4/inode.c:6144 __mark_inode_dirty+0x2cc/0xc90 fs/fs-writeback.c:2522 generic_update_time fs/inode.c:1981 [inline] inode_update_time fs/inode.c:1994 [inline] __file_update_time fs/inode.c:2180 [inline] file_update_time+0x187/0x1a0 fs/inode.c:2210 ext4_page_mkwrite+0x1f9/0x11a0 fs/ext4/inode.c:6262 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 wp_page_shared mm/memory.c:3311 [inline] do_wp_page+0xd4d/0x34d0 mm/memory.c:3396 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1306/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7fd825c70163 RSP: 002b:00007ffdc4e5ef10 EFLAGS: 00010206 RAX: 00007fd8211ffe90 RBX: 00007ffdc4e5f040 RCX: 0000000000000000 RDX: 00007fd8211ffe8c RSI: 0000000000000008 RDI: 00007ffdc4e5f040 RBP: 00000000000003e6 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffdc4e5f020 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000170 R14: fffffffffffffe90 R15: 0000000000000000 INFO: task syz.3.960:8899 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.960 state:D stack:25384 pid:8899 ppid:5775 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x5c9/0xe00 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x10c/0x140 fs/jbd2/transaction.c:1231 __ext4_journal_get_write_access+0x208/0x6d0 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x205/0x2a0 fs/ext4/inode.c:5933 __ext4_mark_inode_dirty+0x13f/0x6d0 fs/ext4/inode.c:6107 ext4_dirty_inode+0xcb/0x110 fs/ext4/inode.c:6144 __mark_inode_dirty+0x2cc/0xc90 fs/fs-writeback.c:2522 generic_update_time fs/inode.c:1981 [inline] inode_update_time fs/inode.c:1994 [inline] __file_update_time fs/inode.c:2180 [inline] file_update_time+0x187/0x1a0 fs/inode.c:2210 ext4_page_mkwrite+0x1f9/0x11a0 fs/ext4/inode.c:6262 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 do_shared_fault mm/memory.c:4717 [inline] do_fault mm/memory.c:4779 [inline] do_pte_missing mm/memory.c:3689 [inline] handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1a2c/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7ff6dd072729 RSP: 002b:00007fff3b8a4480 EFLAGS: 00010202 RAX: 0000001b2dc19000 RBX: ffffffff8a821862 RCX: 0000001b2dc18ff8 RDX: 0000001b2d624220 RSI: 0000000000000008 RDI: 00007ff6ddf55720 RBP: 000000000000017c R08: 00007ff6dd410000 R09: 00007ff6dd412000 R10: 000000008a821866 R11: 000000000000000a R12: 00007ff6dd426218 R13: 0000000000000b56 R14: ffffffff8a8211fb R15: 00007ff6ddf55720 INFO: task syz.0.962:8904 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.962 state:D stack:27560 pid:8904 ppid:5778 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x5c9/0xe00 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x10c/0x140 fs/jbd2/transaction.c:1231 __ext4_journal_get_write_access+0x208/0x6d0 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x205/0x2a0 fs/ext4/inode.c:5933 __ext4_mark_inode_dirty+0x13f/0x6d0 fs/ext4/inode.c:6107 ext4_dirty_inode+0xcb/0x110 fs/ext4/inode.c:6144 __mark_inode_dirty+0x2cc/0xc90 fs/fs-writeback.c:2522 generic_update_time fs/inode.c:1981 [inline] inode_update_time fs/inode.c:1994 [inline] __file_update_time fs/inode.c:2180 [inline] file_update_time+0x187/0x1a0 fs/inode.c:2210 ext4_page_mkwrite+0x1f9/0x11a0 fs/ext4/inode.c:6262 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 do_shared_fault mm/memory.c:4717 [inline] do_fault mm/memory.c:4779 [inline] do_pte_missing mm/memory.c:3689 [inline] handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1a2c/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f7c06c6ba23 RSP: 002b:00007ffdbdfb05a0 EFLAGS: 00010246 RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000001b2d364000 RDX: 0000001b2d324000 RSI: 0000000000400000 RDI: 00007f7c06fe0708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdbdfb0830 Showing all locks held in the system: 1 lock held by khungtaskd/28: #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5525: #0: ffff88823bd6a8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032832f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217 3 locks held by syz-executor/5759: #0: ffff888079e2ea20 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff888079e2ea20 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff888079e2ea20 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5440 #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1e2/0x11a0 fs/ext4/inode.c:6261 #2: ffff88814e470990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1f3f/0x2170 fs/jbd2/transaction.c:448 3 locks held by syz.3.960/8899: #0: ffff88807829d720 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff88807829d720 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff88807829d720 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5440 #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1e2/0x11a0 fs/ext4/inode.c:6261 #2: ffff88814e470990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1f3f/0x2170 fs/jbd2/transaction.c:448 3 locks held by syz.0.962/8904: #0: ffff88807c156a20 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff88807c156a20 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff88807c156a20 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5440 #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff88814e46c510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1e2/0x11a0 fs/ext4/inode.c:6261 #2: ffff88814e470990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1f3f/0x2170 fs/jbd2/transaction.c:448 ============================================= 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+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf59/0xfa0 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 12 Comm: kworker/u4:1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_switch+0x6d/0xe0 kernel/kcov.c:350 Code: 4c 09 01 48 8b 54 24 20 65 4c 8b 05 0d 41 7c 7e 45 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d fb 40 7c 7e <41> 81 e3 00 01 ff 00 74 13 41 81 fb 00 01 00 00 75 d9 41 83 b8 24 RSP: 0018:ffffc90000116d50 EFLAGS: 00000202 RAX: 0000000000000002 RBX: ffffffff8f1b9c70 RCX: 0000000000000003 RDX: ffffffff813baa28 RSI: ffffffff8cfa05a0 RDI: 0000000000000002 RBP: ffffc90000116e98 R08: ffff88801be4da00 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000080000202 R12: ffffffff8f1b9c75 R13: ffffc90000116e48 R14: 0000000000000002 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a6d2613660 CR3: 000000000cf32000 CR4: 00000000003526e0 Call Trace: unwind_next_frame+0x658/0x2990 arch/x86/kernel/unwind_orc.c:505 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843 ieee80211_inform_bss+0xb33/0xfd0 net/mac80211/scan.c:160 rdev_inform_bss+0x106/0x410 net/wireless/rdev-ops.h:418 cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2989 [inline] cfg80211_inform_bss_frame_data+0xb22/0x1330 net/wireless/scan.c:3016 ieee80211_bss_info_update+0x789/0x9f0 net/mac80211/scan.c:211 ieee80211_rx_bss_info net/mac80211/ibss.c:1124 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1613 [inline] ieee80211_ibss_rx_queued_mgmt+0x18f5/0x2dc0 net/mac80211/ibss.c:1642 ieee80211_iface_process_skb net/mac80211/iface.c:1661 [inline] ieee80211_iface_work+0x730/0xc90 net/mac80211/iface.c:1715 cfg80211_wiphy_work+0x228/0x260 net/wireless/core.c:437 process_one_work kernel/workqueue.c:2657 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293