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INFO: task hung in d_alloc_parallel (2)

Status: upstream: reported C repro on 2024/11/04 12:30
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+30f73869d6de512e814b@syzkaller.appspotmail.com
First crash: 48d, last: 12h23m
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2024/11/09 linux-6.1.y (ToT) d7039b844a1c C [report] INFO: task hung in d_alloc_parallel
2024/11/09 upstream (ToT) da4373fbcf00 C Didn't crash
▶ ▼ Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 INFO: task hung in d_alloc_parallel 85 1929d 2079d 0/3 auto-closed as invalid on 2020/01/08 20:52
linux-5.15 INFO: task hung in d_alloc_parallel origin:upstream C 73 3d09h 248d 0/3 upstream: reported C repro on 2024/04/18 05:41
linux-4.14 INFO: task hung in d_alloc_parallel C error 4 1348d 1957d 0/1 upstream: reported C repro on 2019/08/14 00:43
android-414 INFO: task hung in d_alloc_parallel 1 1889d 1889d 0/1 auto-closed as invalid on 2020/02/18 04:29
linux-4.19 INFO: task hung in d_alloc_parallel vfs C error 5 678d 1695d 0/1 upstream: reported C repro on 2020/05/01 20:49
upstream INFO: task hung in d_alloc_parallel fuse 213 2123d 2454d 0/28 closed as dup on 2018/09/08 15:40
linux-6.1 INFO: task hung in d_alloc_parallel 43 128d 251d 0/3 auto-obsoleted due to no activity on 2024/10/24 17:53
upstream INFO: task hung in d_alloc_parallel (2) fs C done error 1383 22h08m 1887d 0/28 upstream: reported C repro on 2019/10/22 22:44

Sample crash report:
INFO: task syz-executor367:4345 blocked for more than 143 seconds.
      Tainted: G        W          6.1.121-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor367 state:D stack:0     pid:4345  ppid:4331   flags:0x00000005
Call trace:
 __switch_to+0x308/0x598 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0xef4/0x1d44 kernel/sched/core.c:6558
 schedule+0xc4/0x170 kernel/sched/core.c:6634
 d_wait_lookup+0x1a0/0x27c fs/dcache.c:2632
 d_alloc_parallel+0x9b0/0x1184 fs/dcache.c:2714
 __lookup_slow+0x108/0x374 fs/namei.c:1675
 lookup_slow+0x60/0x84 fs/namei.c:1707
 walk_component fs/namei.c:1998 [inline]
 link_path_walk+0x830/0xcc8 fs/namei.c:2325
 path_lookupat+0x90/0x3d0 fs/namei.c:2478
 do_o_path+0xa8/0x214 fs/namei.c:3754
 path_openat+0x203c/0x2548 fs/namei.c:3776
 do_filp_open+0x1bc/0x3cc fs/namei.c:3810
 do_sys_openat2+0x128/0x3e0 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
INFO: task syz-executor367:4346 blocked for more than 143 seconds.
      Tainted: G        W          6.1.121-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor367 state:D stack:0     pid:4346  ppid:4332   flags:0x00000005
Call trace:
 __switch_to+0x308/0x598 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0xef4/0x1d44 kernel/sched/core.c:6558
 schedule+0xc4/0x170 kernel/sched/core.c:6634
 d_wait_lookup+0x1a0/0x27c fs/dcache.c:2632
 d_alloc_parallel+0x9b0/0x1184 fs/dcache.c:2714
 __lookup_slow+0x108/0x374 fs/namei.c:1675
 lookup_slow+0x60/0x84 fs/namei.c:1707
 walk_component fs/namei.c:1998 [inline]
 link_path_walk+0x830/0xcc8 fs/namei.c:2325
 path_lookupat+0x90/0x3d0 fs/namei.c:2478
 do_o_path+0xa8/0x214 fs/namei.c:3754
 path_openat+0x203c/0x2548 fs/namei.c:3776
 do_filp_open+0x1bc/0x3cc fs/namei.c:3810
 do_sys_openat2+0x128/0x3e0 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
INFO: task syz-executor367:4347 blocked for more than 143 seconds.
      Tainted: G        W          6.1.121-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor367 state:D stack:0     pid:4347  ppid:4329   flags:0x00000005
Call trace:
 __switch_to+0x308/0x598 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0xef4/0x1d44 kernel/sched/core.c:6558
 schedule+0xc4/0x170 kernel/sched/core.c:6634
 d_wait_lookup+0x1a0/0x27c fs/dcache.c:2632
 d_alloc_parallel+0x9b0/0x1184 fs/dcache.c:2714
 __lookup_slow+0x108/0x374 fs/namei.c:1675
 lookup_slow+0x60/0x84 fs/namei.c:1707
 walk_component fs/namei.c:1998 [inline]
 link_path_walk+0x830/0xcc8 fs/namei.c:2325
 path_lookupat+0x90/0x3d0 fs/namei.c:2478
 do_o_path+0xa8/0x214 fs/namei.c:3754
 path_openat+0x203c/0x2548 fs/namei.c:3776
 do_filp_open+0x1bc/0x3cc fs/namei.c:3810
 do_sys_openat2+0x128/0x3e0 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
INFO: task syz-executor367:4348 blocked for more than 143 seconds.
      Tainted: G        W          6.1.121-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor367 state:D stack:0     pid:4348  ppid:4328   flags:0x00000005
Call trace:
 __switch_to+0x308/0x598 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0xef4/0x1d44 kernel/sched/core.c:6558
 schedule+0xc4/0x170 kernel/sched/core.c:6634
 d_wait_lookup+0x1a0/0x27c fs/dcache.c:2632
 d_alloc_parallel+0x9b0/0x1184 fs/dcache.c:2714
 __lookup_slow+0x108/0x374 fs/namei.c:1675
 lookup_slow+0x60/0x84 fs/namei.c:1707
 walk_component fs/namei.c:1998 [inline]
 link_path_walk+0x830/0xcc8 fs/namei.c:2325
 path_lookupat+0x90/0x3d0 fs/namei.c:2478
 do_o_path+0xa8/0x214 fs/namei.c:3754
 path_openat+0x203c/0x2548 fs/namei.c:3776
 do_filp_open+0x1bc/0x3cc fs/namei.c:3810
 do_sys_openat2+0x128/0x3e0 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
INFO: task syz-executor367:4344 blocked for more than 143 seconds.
      Tainted: G        W          6.1.121-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor367 state:D stack:0     pid:4344  ppid:4330   flags:0x00000005
Call trace:
 __switch_to+0x308/0x598 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0xef4/0x1d44 kernel/sched/core.c:6558
 schedule+0xc4/0x170 kernel/sched/core.c:6634
 d_wait_lookup+0x1a0/0x27c fs/dcache.c:2632
 d_alloc_parallel+0x9b0/0x1184 fs/dcache.c:2714
 __lookup_slow+0x108/0x374 fs/namei.c:1675
 lookup_slow+0x60/0x84 fs/namei.c:1707
 walk_component fs/namei.c:1998 [inline]
 link_path_walk+0x830/0xcc8 fs/namei.c:2325
 path_lookupat+0x90/0x3d0 fs/namei.c:2478
 do_o_path+0xa8/0x214 fs/namei.c:3754
 path_openat+0x203c/0x2548 fs/namei.c:3776
 do_filp_open+0x1bc/0x3cc fs/namei.c:3810
 do_sys_openat2+0x128/0x3e0 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffff800015c65570 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xd10 kernel/rcu/tasks.h:543
1 lock held by rcu_tasks_trace/13:
 #0: ffff800015c65d90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xd10 kernel/rcu/tasks.h:543
1 lock held by khungtaskd/28:
 #0: ffff800015c653a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349
2 locks held by getty/4051:
 #0: ffff0000d639f098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80001d8202f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1214 drivers/tty/n_tty.c:2198
1 lock held by syz-executor367/4336:
1 lock held by syz-executor367/4345:
 #0: ffff0000e4c38188 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline]
 #0: ffff0000e4c38188 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x50/0x84 fs/namei.c:1706
1 lock held by syz-executor367/4342:
1 lock held by syz-executor367/4346:
 #0: ffff0000df4746d0 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline]
 #0: ffff0000df4746d0 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x50/0x84 fs/namei.c:1706
1 lock held by syz-executor367/4338:
1 lock held by syz-executor367/4347:
 #0: ffff0000e4c386d0 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline]
 #0: ffff0000e4c386d0 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x50/0x84 fs/namei.c:1706
2 locks held by syz-executor367/4340:
1 lock held by syz-executor367/4348:
 #0: ffff0000e4c38c18 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline]
 #0: ffff0000e4c38c18 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x50/0x84 fs/namei.c:1706
1 lock held by syz-executor367/4343:
1 lock held by syz-executor367/4344:
 #0: ffff0000df474188 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline]
 #0: ffff0000df474188 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x50/0x84 fs/namei.c:1706
1 lock held by dhcpcd/4368:
 #0: ffff0000c084a130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1750 [inline]
 #0: ffff0000c084a130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x4c/0xb58 net/packet/af_packet.c:3263

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

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/22 04:17 linux-6.1.y 29f02ec58a94 d7f584ee .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 INFO: task hung in d_alloc_parallel
2024/11/04 12:29 linux-6.1.y 7c15117f9468 f00eed24 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 INFO: task hung in d_alloc_parallel
2024/12/08 14:47 linux-6.1.y e4d90d63d385 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in d_alloc_parallel
2024/11/18 21:33 linux-6.1.y b67dc5c9ade9 e7bb5d6e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in d_alloc_parallel
2024/12/18 03:29 linux-6.1.y 52f863f820fd a0626d3a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: task hung in d_alloc_parallel
* Struck through repros no longer work on HEAD.