BUG: soft lockup in kernfs_fop_open

Status: auto-obsoleted due to no activity on 2024/10/23 00:09
Reported-by: syzbot+14edefbf83d136c1cc65@syzkaller.appspotmail.com
First crash: 835d, last: 736d
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in kernfs_fop_open (2) 1 1 20d 20d 0/3 upstream: reported on 2026/07/10 06:09
upstream INFO: rcu detected stall in kernfs_fop_open (3) kernfs 1 2 1499d 1548d 0/29 auto-closed as invalid on 2022/09/20 22:08
upstream INFO: rcu detected stall in kernfs_fop_open (4) kernel 1 1 1338d 1338d 0/29 auto-obsoleted due to no activity on 2023/03/09 20:29
linux-5.15 INFO: rcu detected stall in kernfs_fop_open 1 1 1150d 1150d 0/3 auto-obsoleted due to no activity on 2023/09/14 10:24
upstream INFO: rcu detected stall in kernfs_fop_open (7) prio:high kernfs 1 syz, C error error 12 3d17h 367d 0/29 upstream: reported C repro on 2025/07/28 23:27
linux-6.1 INFO: rcu detected stall in kernfs_fop_open 1 1 521d 521d 0/3 auto-obsoleted due to no activity on 2025/06/04 16:10
upstream INFO: rcu detected stall in kernfs_fop_open (6) mm 1 17 558d 662d 0/29 auto-obsoleted due to no activity on 2025/04/18 13:25
upstream INFO: rcu detected stall in kernfs_fop_open (5) cgroups 1 2 954d 1000d 0/29 auto-obsoleted due to no activity on 2024/03/18 04:35

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [syz.0.952:3158]
Modules linked in:
CPU: 0 PID: 3158 Comm: syz.0.952 Tainted: G        W         5.15.151-syzkaller-00059-g5356d2f17edf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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 2b 02 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:ffffc900009a7360 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffff92000134e70 RCX: 1ffffffff0d1aa9c
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8881f7038ad4
RBP: ffffc900009a7410 R08: dffffc0000000000 R09: ffffed103ee0715b
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881f7038ad4 R14: 0000000000000001 R15: 1ffff92000134e74
FS:  00007f20b6a626c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002b00 CR3: 00000001260b9000 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_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/0x48c
 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:1880 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1917
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 kernfs_get_open_node fs/kernfs/file.c:547 [inline]
 kernfs_fop_open+0x73c/0xab0 fs/kernfs/file.c:698
 do_dentry_open+0x81c/0xfd0 fs/open.c:828
 vfs_open+0x73/0x80 fs/open.c:958
 do_open fs/namei.c:3608 [inline]
 path_openat+0x26f0/0x2f40 fs/namei.c:3742
 do_filp_open+0x21c/0x460 fs/namei.c:3769
 do_sys_openat2+0x13f/0x830 fs/open.c:1234
 do_sys_open fs/open.c:1250 [inline]
 __do_sys_openat fs/open.c:1266 [inline]
 __se_sys_openat fs/open.c:1261 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1261
 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: 0033:0x7f20b7de0f19
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:00007f20b6a62048 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f20b7f70f60 RCX: 00007f20b7de0f19
RDX: 0000000000000002 RSI: 0000000020002b00 RDI: 0000000000000003
RBP: 00007f20b7e4fe68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f20b7f70f60 R15: 00007fffe7609ec8
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3081 Comm: syz-executor Tainted: G        W         5.15.151-syzkaller-00059-g5356d2f17edf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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 2b 02 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:ffffc90000c27340 EFLAGS: 00000246
RAX: 0000000000000003 RBX: 1ffff92000184e6c RCX: ffffffff815504ef
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff888105d8ec18
RBP: ffffc90000c273f0 R08: dffffc0000000000 R09: ffffed1020bb1d84
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff888105d8ec18 R14: 0000000000000003 R15: 1ffff92000184e70
FS:  00005555568ac500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d01fffc CR3: 0000000112c9b000 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_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/0x48c
 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:1880 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1917
 __bpf_trace_kfree+0x6f/0x90 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/0x48c
 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:1880 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1917
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 skb_free_head net/core/skbuff.c:656 [inline]
 skb_release_data+0x8a9/0xa80 net/core/skbuff.c:678
 skb_release_all net/core/skbuff.c:743 [inline]
 __kfree_skb net/core/skbuff.c:757 [inline]
 consume_skb+0xac/0x250 net/core/skbuff.c:930
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x8e7/0xac0 net/netlink/af_netlink.c:1356
 netlink_sendmsg+0xa0a/0xd20 net/netlink/af_netlink.c:1924
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 __sys_sendto+0x564/0x720 net/socket.c:2058
 __do_sys_sendto net/socket.c:2070 [inline]
 __se_sys_sendto net/socket.c:2066 [inline]
 __x64_sys_sendto+0xe5/0x100 net/socket.c:2066
 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: 0033:0x7fa27222ec53
Code: 64 89 02 48 c7 c0 ff ff ff ff eb b7 66 2e 0f 1f 84 00 00 00 00 00 90 80 3d f1 d8 15 00 00 41 89 ca 74 14 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 75 c3 0f 1f 40 00 55 48 83 ec 30 44 89 4c 24
RSP: 002b:00007ffff9d7bcb8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fa272eeb620 RCX: 00007fa27222ec53
RDX: 0000000000000040 RSI: 00007fa272eeb670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffff9d7bcd4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fa272eeb670 R15: 0000000000000000
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/25 00:02 android13-5.15-lts 5356d2f17edf d1a1b0ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in kernfs_fop_open
2024/07/13 22:53 android13-5.15-lts db06c48ab67e eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in kernfs_fop_open
2024/07/13 22:49 android13-5.15-lts db06c48ab67e eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in kernfs_fop_open
2024/04/29 03:36 android13-5.15-lts 5d96939590c0 07b455f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: soft lockup in kernfs_fop_open
2024/04/20 09:42 android13-5.15-lts ad06eaf051cd af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: soft lockup in kernfs_fop_open
2024/04/18 22:44 android13-5.15-lts ad06eaf051cd af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: soft lockup in kernfs_fop_open
2024/04/16 22:27 android13-5.15-lts ad06eaf051cd 18f6e127 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: soft lockup in kernfs_fop_open
* Struck through repros no longer work on HEAD.