BUG: soft lockup in kernfs_fop_release

Status: auto-obsoleted due to no activity on 2024/07/22 00:19
Reported-by: syzbot+3012dddfa496fa509d70@syzkaller.appspotmail.com
First crash: 846d, last: 841d
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in kernfs_fop_release kernfs 1 syz, C error 8 351d 1410d 0/29 auto-obsoleted due to no activity on 2025/12/04 02:18
linux-5.15 INFO: rcu detected stall in kernfs_fop_release 1 2 709d 714d 0/3 auto-obsoleted due to no activity on 2024/12/10 13:10
upstream INFO: rcu detected stall in kernfs_fop_release (2) bpf kernfs 1 3 230d 242d 0/29 auto-obsoleted due to no activity on 2026/03/24 14:55

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 215s! [udevd:101]
Modules linked in:
CPU: 0 PID: 101 Comm: udevd Tainted: G        W         5.15.148-syzkaller-00013-gad06eaf051cd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 5b 03 f3 03 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc90000a47680 EFLAGS: 00000246
RAX: 0000000000000003 RBX: 1ffff92000148ed4 RCX: ffffffff8154f88f
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff88810ab9bd08
RBP: ffffc90000a47730 R08: dffffc0000000000 R09: ffffed10215737a2
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88810ab9bd08 R14: 0000000000000003 R15: 1ffff92000148ed8
FS:  00007f07fb2b9c80(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f9832c5e1 CR3: 000000010cb70000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x6bc/0xc40 kernel/locking/qspinlock.c:508
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x4a4
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 __traceiter_kfree+0x2a/0x40 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 sk_psock_free_link include/linux/skmsg.h:420 [inline]
 sock_map_del_link net/core/sock_map.c:160 [inline]
 sock_map_unref+0x352/0x4d0 net/core/sock_map.c:182
 sock_hash_delete_elem+0x274/0x2f0 net/core/sock_map.c:941
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x4a4
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 __traceiter_kfree+0x2a/0x40 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 kernfs_fop_release+0x1e0/0x250 fs/kernfs/file.c:762
 __fput+0x3fe/0x910 fs/file_table.c:280
 ____fput+0x15/0x20 fs/file_table.c:308
 task_work_run+0x129/0x190 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xc4/0xe0 kernel/entry/common.c:175
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x160 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f07fb3e837f
Code: af 6a 0d 00 f7 d8 64 89 02 48 83 c8 ff 44 89 c7 48 89 04 24 e8 e1 fc f9 ff 48 8b 04 24 48 83 c4 28 c3 c3 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 7a 6a 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007fff92add408 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 000055c2221febc0 RCX: 00007f07fb3e837f
RDX: 00007f07fb4bb860 RSI: 0000000000000001 RDI: 000000000000000c
RBP: 0000000000000000 R08: 000000000000000c R09: 0000000000000000
R10: 0000000000000010 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000007 R14: 0000000000000001 R15: 000055c2211aafc1
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10631 Comm: syz-executor.0 Tainted: G        W         5.15.148-syzkaller-00013-gad06eaf051cd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 5b 03 f3 03 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc90000ac7580 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffff92000158eb4 RCX: 1ffffffff0d1aa9c
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8881f7137ed4
RBP: ffffc90000ac7630 R08: dffffc0000000000 R09: ffffed103ee26fdb
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881f7137ed4 R14: 0000000000000001 R15: 1ffff92000158eb8
FS:  00007ffbf01766c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31423000 CR3: 000000012397e000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_node kernel/locking/qspinlock_paravirt.h:325 [inline]
 __pv_queued_spin_lock_slowpath+0x41b/0xc40 kernel/locking/qspinlock.c:473
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x4a4
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 __traceiter_kfree+0x2a/0x40 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 ida_alloc_range+0x987/0xa80 lib/idr.c:460
 get_anon_bdev fs/super.c:1049 [inline]
 set_anon_super fs/super.c:1069 [inline]
 set_anon_super_fc+0x2c/0xb0 fs/super.c:1091
 sget_fc+0x2b0/0x620 fs/super.c:548
 vfs_get_super fs/super.c:1154 [inline]
 get_tree_nodev+0x2a/0x160 fs/super.c:1189
 ramfs_get_tree+0x1c/0x20 fs/ramfs/inode.c:249
 vfs_get_tree+0x88/0x290 fs/super.c:1517
 do_new_mount+0x2ba/0xb30 fs/namespace.c:3005
 path_mount+0x671/0x1070 fs/namespace.c:3335
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2c4/0x3b0 fs/namespace.c:3533
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7ffbf1402ea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007ffbf01760c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffbf1530f80 RCX: 00007ffbf1402ea9
RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000000000000
RBP: 00007ffbf144f4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007ffbf1530f80 R15: 00007fffa183db98
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/23 00:11 android13-5.15-lts ad06eaf051cd 36c961ad .config console log report info ci2-android-5-15 BUG: soft lockup in kernfs_fop_release
2024/04/17 20:15 android13-5.15-lts ad06eaf051cd acc528cb .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in kernfs_fop_release
* Struck through repros no longer work on HEAD.