INFO: task syz.4.622:8571 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.622 state:D stack:26512 pid:8571 ppid:6759 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832 rwsem_down_read_slowpath+0x4f8/0x840 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1250 [inline] __down_read kernel/locking/rwsem.c:1263 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1522 inode_lock_shared include/linux/fs.h:814 [inline] open_last_lookups fs/namei.c:3555 [inline] path_openat+0x7b7/0x3190 fs/namei.c:3786 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_open_execat+0x133/0x3d0 fs/exec.c:924 bprm_execve+0x567/0x16f0 fs/exec.c:1867 do_execveat_common+0x51b/0x6c0 fs/exec.c:1998 do_execveat fs/exec.c:2083 [inline] __do_sys_execveat fs/exec.c:2157 [inline] __se_sys_execveat fs/exec.c:2151 [inline] __x64_sys_execveat+0xc4/0xe0 fs/exec.c:2151 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f0911d8eba9 RSP: 002b:00007f0912ca6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000142 RAX: ffffffffffffffda RBX: 00007f0911fd6090 RCX: 00007f0911d8eba9 RDX: 0000000000000000 RSI: 0000200000000140 RDI: ffffffffffffff9c RBP: 00007f0911e11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0911fd6128 R14: 00007f0911fd6090 R15: 00007fff772734d8 Showing all locks held in the system: 3 locks held by kworker/u4:0/11: #0: ffff8880b8e3c458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #1: ffff8880b8e289c0 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline] #1: ffff8880b8e289c0 (psi_seq){-.-.}-{0:0}, at: __schedule+0x20ee/0x44d0 kernel/sched/core.c:6694 #2: ffff8880b8e2a898 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999 1 lock held by khungtaskd/28: #0: ffffffff8cd2fe20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2fe20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2fe20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5549: #0: ffff88814cd8b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 2 locks held by syz.4.622/8566: 2 locks held by syz.4.622/8571: #0: ffff88802c209988 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: prepare_bprm_creds fs/exec.c:1499 [inline] #0: ffff88802c209988 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0xca/0x16f0 fs/exec.c:1854 #1: ffff88804c0a4198 (&type->i_mutex_dir_key#26){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:814 [inline] #1: ffff88804c0a4198 (&type->i_mutex_dir_key#26){++++}-{3:3}, at: open_last_lookups fs/namei.c:3555 [inline] #1: ffff88804c0a4198 (&type->i_mutex_dir_key#26){++++}-{3:3}, at: path_openat+0x7b7/0x3190 fs/namei.c:3786 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 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+0xf41/0xf80 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8566 Comm: syz.4.622 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__sanitizer_cov_trace_switch+0x7c/0x120 kernel/kcov.c:-1 Code: c0 75 13 e9 bc 00 00 00 b9 01 00 00 00 48 85 c0 0f 84 ae 00 00 00 41 57 41 56 41 54 53 48 8b 54 24 20 65 4c 8b 05 84 24 7e 7e <45> 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d RSP: 0018:ffffc9000c96d9f0 EFLAGS: 00000206 RAX: 0000000000000003 RBX: ffffffff8ed92e55 RCX: 0000000000000003 RDX: ffffffff813ab106 RSI: ffffffff8cb9e7b0 RDI: 0000000000000002 RBP: ffffc9000c96db38 R08: ffff888027a78000 R09: 0000000000000008 R10: 0000000000000009 R11: 0000000000000002 R12: ffffc9000c96dae8 R13: dffffc0000000000 R14: 0000000000000002 R15: ffffffff8ed92e54 FS: 00007f0912cc76c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7659fa4198 CR3: 0000000064162000 CR4: 00000000003506f0 Call Trace: unwind_next_frame+0xe46/0x2970 arch/x86/kernel/unwind_orc.c:581 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3852 free_buffer_head+0x56/0x220 fs/buffer.c:3043 try_to_free_buffers+0x255/0x520 fs/buffer.c:2984 shrink_folio_list+0x2024/0x7980 mm/vmscan.c:2075 evict_folios+0xa85/0x2290 mm/vmscan.c:5208 try_to_shrink_lruvec+0x856/0xb80 mm/vmscan.c:5409 lru_gen_shrink_lruvec mm/vmscan.c:5553 [inline] shrink_lruvec+0x4ce/0x28b0 mm/vmscan.c:6303 shrink_node_memcgs mm/vmscan.c:6523 [inline] shrink_node+0x920/0x3790 mm/vmscan.c:6558 shrink_zones mm/vmscan.c:6800 [inline] do_try_to_free_pages+0x65f/0x1aa0 mm/vmscan.c:6862 try_to_free_mem_cgroup_pages+0x2f5/0x790 mm/vmscan.c:7177 try_charge_memcg+0x61c/0x1810 mm/memcontrol.c:2694 obj_cgroup_charge_pages mm/memcontrol.c:3109 [inline] obj_cgroup_charge+0x358/0x620 mm/memcontrol.c:3400 memcg_slab_pre_alloc_hook mm/slab.h:508 [inline] slab_pre_alloc_hook+0x2eb/0x310 mm/slab.h:719 slab_alloc_node mm/slub.c:3477 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x5a/0x2e0 mm/slub.c:3519 kmem_cache_zalloc include/linux/slab.h:711 [inline] alloc_buffer_head+0x2d/0x280 fs/buffer.c:3027 folio_alloc_buffers+0x39b/0x990 fs/buffer.c:935 folio_create_empty_buffers+0x3a/0x730 fs/buffer.c:1648 block_read_full_folio+0x213/0xf40 fs/buffer.c:2386 filemap_read_folio+0x167/0x760 mm/filemap.c:2420 do_read_cache_folio+0x470/0x7e0 mm/filemap.c:3789 do_read_cache_page+0x32/0x250 mm/filemap.c:3855 read_mapping_page include/linux/pagemap.h:892 [inline] dir_get_page fs/sysv/dir.c:64 [inline] sysv_find_entry+0x196/0x3f0 fs/sysv/dir.c:157 sysv_inode_by_name+0x31/0x140 fs/sysv/dir.c:374 sysv_lookup+0x6a/0xe0 fs/sysv/namei.c:38 lookup_open fs/namei.c:3466 [inline] open_last_lookups fs/namei.c:3556 [inline] path_openat+0x10b8/0x3190 fs/namei.c:3786 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f0911d8eba9 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:00007f0912cc7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f0911fd5fa0 RCX: 00007f0911d8eba9 RDX: 0000000000000040 RSI: 0000200000000100 RDI: ffffffffffffff9c RBP: 00007f0911e11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000001ff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0911fd6038 R14: 00007f0911fd5fa0 R15: 00007fff772734d8