syzbot

INFO: task syz-executor251:5256 blocked for more than 143 seconds.
      Not tainted 6.11.0-rc5-syzkaller-00176-g20371ba12063 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor251 state:D stack:27704 pid:5256  tgid:5242  ppid:5238   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 d_wait_lookup fs/dcache.c:2463 [inline]
 d_alloc_parallel+0xc16/0x1600 fs/dcache.c:2545
 __lookup_slow+0x117/0x3f0 fs/namei.c:1703
 lookup_slow+0x53/0x70 fs/namei.c:1735
 walk_component fs/namei.c:2039 [inline]
 link_path_walk+0x99b/0xea0 fs/namei.c:2404
 path_lookupat+0xa9/0x450 fs/namei.c:2565
 filename_lookup+0x256/0x610 fs/namei.c:2595
 user_path_at+0x3a/0x60 fs/namei.c:3002
 do_mount fs/namespace.c:3809 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:3997
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f05ca160b89
RSP: 002b:00007f05ca0f5238 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f05ca1f26b8 RCX: 00007f05ca160b89
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000000
RBP: 00007f05ca1f26b0 R08: 0000000000000000 R09: 00007f05ca0f56c0
R10: 0000000000101091 R11: 0000000000000246 R12: 00007f05ca1b50c0
R13: 000000000000006e R14: 00007ffef128d550 R15: 00007ffef128d638
 </TASK>
INFO: task syz-executor251:5257 blocked for more than 144 seconds.
      Not tainted 6.11.0-rc5-syzkaller-00176-g20371ba12063 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor251 state:D stack:28064 pid:5257  tgid:5243  ppid:5237   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 d_wait_lookup fs/dcache.c:2463 [inline]
 d_alloc_parallel+0xc16/0x1600 fs/dcache.c:2545
 __lookup_slow+0x117/0x3f0 fs/namei.c:1703
 lookup_slow+0x53/0x70 fs/namei.c:1735
 walk_component fs/namei.c:2039 [inline]
 link_path_walk+0x99b/0xea0 fs/namei.c:2404
 path_lookupat+0xa9/0x450 fs/namei.c:2565
 filename_lookup+0x256/0x610 fs/namei.c:2595
 user_path_at+0x3a/0x60 fs/namei.c:3002
 do_mount fs/namespace.c:3809 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:3997
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f05ca160b89
RSP: 002b:00007f05ca0f5238 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f05ca1f26b8 RCX: 00007f05ca160b89
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000000
RBP: 00007f05ca1f26b0 R08: 0000000000000000 R09: 00007f05ca0f56c0
R10: 0000000000101091 R11: 0000000000000246 R12: 00007f05ca1b50c0
R13: 000000000000006e R14: 00007ffef128d550 R15: 00007ffef128d638
 </TASK>
INFO: task syz-executor251:5258 blocked for more than 145 seconds.
      Not tainted 6.11.0-rc5-syzkaller-00176-g20371ba12063 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor251 state:D stack:28064 pid:5258  tgid:5244  ppid:5240   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 d_wait_lookup fs/dcache.c:2463 [inline]
 d_alloc_parallel+0xc16/0x1600 fs/dcache.c:2545
 __lookup_slow+0x117/0x3f0 fs/namei.c:1703
 lookup_slow+0x53/0x70 fs/namei.c:1735
 walk_component fs/namei.c:2039 [inline]
 link_path_walk+0x99b/0xea0 fs/namei.c:2404
 path_lookupat+0xa9/0x450 fs/namei.c:2565
 filename_lookup+0x256/0x610 fs/namei.c:2595
 user_path_at+0x3a/0x60 fs/namei.c:3002
 do_mount fs/namespace.c:3809 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:3997
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f05ca160b89
RSP: 002b:00007f05ca0f5238 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f05ca1f26b8 RCX: 00007f05ca160b89
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000000
RBP: 00007f05ca1f26b0 R08: 0000000000000000 R09: 00007f05ca0f56c0
R10: 0000000000101091 R11: 0000000000000246 R12: 00007f05ca1b50c0
R13: 000000000000006e R14: 00007ffef128d550 R15: 00007ffef128d638
 </TASK>
INFO: task syz-executor251:5260 blocked for more than 145 seconds.
      Not tainted 6.11.0-rc5-syzkaller-00176-g20371ba12063 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor251 state:D stack:28064 pid:5260  tgid:5245  ppid:5239   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 d_wait_lookup fs/dcache.c:2463 [inline]
 d_alloc_parallel+0xc16/0x1600 fs/dcache.c:2545
 __lookup_slow+0x117/0x3f0 fs/namei.c:1703
 lookup_slow+0x53/0x70 fs/namei.c:1735
 walk_component fs/namei.c:2039 [inline]
 link_path_walk+0x99b/0xea0 fs/namei.c:2404
 path_lookupat+0xa9/0x450 fs/namei.c:2565
 filename_lookup+0x256/0x610 fs/namei.c:2595
 user_path_at+0x3a/0x60 fs/namei.c:3002
 do_mount fs/namespace.c:3809 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:3997
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f05ca160b89
RSP: 002b:00007f05ca0f5238 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f05ca1f26b8 RCX: 00007f05ca160b89
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000000
RBP: 00007f05ca1f26b0 R08: 0000000000000000 R09: 00007f05ca0f56c0
R10: 0000000000101091 R11: 0000000000000246 R12: 00007f05ca1b50c0
R13: 000000000000006e R14: 00007ffef128d550 R15: 00007ffef128d638
 </TASK>
INFO: task syz-executor251:5259 blocked for more than 146 seconds.
      Not tainted 6.11.0-rc5-syzkaller-00176-g20371ba12063 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor251 state:D stack:28064 pid:5259  tgid:5246  ppid:5241   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 d_wait_lookup fs/dcache.c:2463 [inline]
 d_alloc_parallel+0xc16/0x1600 fs/dcache.c:2545
 __lookup_slow+0x117/0x3f0 fs/namei.c:1703
 lookup_slow+0x53/0x70 fs/namei.c:1735
 walk_component fs/namei.c:2039 [inline]
 link_path_walk+0x99b/0xea0 fs/namei.c:2404
 path_lookupat+0xa9/0x450 fs/namei.c:2565
 filename_lookup+0x256/0x610 fs/namei.c:2595
 user_path_at+0x3a/0x60 fs/namei.c:3002
 do_mount fs/namespace.c:3809 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:3997
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f05ca160b89
RSP: 002b:00007f05ca0f5238 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f05ca1f26b8 RCX: 00007f05ca160b89
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000000
RBP: 00007f05ca1f26b0 R08: 0000000000000000 R09: 00007f05ca0f56c0
R10: 0000000000101091 R11: 0000000000000246 R12: 00007f05ca1b50c0
R13: 000000000000006e R14: 00007ffef128d550 R15: 00007ffef128d638
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626
1 lock held by kswapd0/88:
2 locks held by getty/4975:
 #0: ffff88802f90a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000311b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211
1 lock held by syz-executor251/5247:
1 lock held by syz-executor251/5256:
 #0: ffff88807c6486c0 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:810 [inline]
 #0: ffff88807c6486c0 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1734
3 locks held by syz-executor251/5248:
1 lock held by syz-executor251/5257:
 #0: ffff88807c7986c0 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:810 [inline]
 #0: ffff88807c7986c0 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1734
2 locks held by syz-executor251/5249:
1 lock held by syz-executor251/5258:
 #0: ffff88807c648180 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:810 [inline]
 #0: ffff88807c648180 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1734
1 lock held by syz-executor251/5251:
1 lock held by syz-executor251/5260:
 #0: ffff88807c798180 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:810 [inline]
 #0: ffff88807c798180 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1734
2 locks held by syz-executor251/5250:
1 lock held by syz-executor251/5259:
 #0: ffff88807c648c00 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:810 [inline]
 #0: ffff88807c648c00 (&type->i_mutex_dir_key#6){.+.+}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1734

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc5-syzkaller-00176-g20371ba12063 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xff4/0x1040 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5248 Comm: syz-executor251 Not tainted 6.11.0-rc5-syzkaller-00176-g20371ba12063 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
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_const_cmp4+0x11/0x90 kernel/kcov.c:313
Code: 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 65 48 8b 14 25 c0 d6 03 00 <65> 8b 05 90 46 70 7e 25 00 01 ff 00 74 10 3d 00 01 00 00 75 5b 83
RSP: 0018:ffffc90003b2eff0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc90003b2f068 RCX: ffffffff91531000
RDX: ffff88802ab29e00 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffffff814125f8 R09: ffffffff814140bf
R10: 0000000000000003 R11: ffff88802ab29e00 R12: ffff88802ab29e00
R13: ffffffff817f2eb0 R14: dffffc0000000000 R15: 1ffff92000765e0d
FS:  00007f05ca1166c0(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559c9e5d0558 CR3: 000000005dee0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 unwind_get_return_address+0x68/0xc0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0x125/0x1b0 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3988 [inline]
 slab_alloc_node mm/slub.c:4037 [inline]
 kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044
 alloc_buffer_head+0x2a/0x290 fs/buffer.c:3025
 folio_alloc_buffers+0x241/0x5b0 fs/buffer.c:929
 create_empty_buffers+0x3a/0x740 fs/buffer.c:1671
 block_read_full_folio+0x25c/0xcd0 fs/buffer.c:2387
 filemap_read_folio+0x1a0/0x790 mm/filemap.c:2355
 do_read_cache_folio+0x134/0x820 mm/filemap.c:3789
 do_read_cache_page+0x30/0x200 mm/filemap.c:3855
 read_mapping_page include/linux/pagemap.h:907 [inline]
 dir_get_page fs/sysv/dir.c:64 [inline]
 sysv_find_entry+0x1af/0x410 fs/sysv/dir.c:157
 sysv_inode_by_name+0x98/0x1f0 fs/sysv/dir.c:374
 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38
 __lookup_slow+0x28c/0x3f0 fs/namei.c:1718
 lookup_slow+0x53/0x70 fs/namei.c:1735
 walk_component fs/namei.c:2039 [inline]
 link_path_walk+0x99b/0xea0 fs/namei.c:2404
 path_lookupat+0xa9/0x450 fs/namei.c:2565
 filename_lookup+0x256/0x610 fs/namei.c:2595
 user_path_at+0x3a/0x60 fs/namei.c:3002
 do_mount fs/namespace.c:3809 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:3997
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f05ca160b89
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 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:00007f05ca116238 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f05ca1f26a8 RCX: 00007f05ca160b89
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000000
RBP: 00007f05ca1f26a0 R08: 0000000000000000 R09: 00007f05ca1166c0
R10: 0000000000101091 R11: 0000000000000246 R12: 00007f05ca1b50c0
R13: 0000000000000006 R14: 00007ffef128d550 R15: 00007ffef128d638
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.772 msecs