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INFO: rcu detected stall in sys_select

Status: auto-obsoleted due to no activity on 2025/11/30 01:55
Subsystems: fs
[Documentation on labels]
First crash: 111d, last: 111d

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7772/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=23453, q=1528 ncpus=2)
task:syz.2.373       state:R  running task     stack:28392 pid:7772  tgid:7768  ppid:5867   task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288
 irqentry_exit+0x36/0x90 kernel/entry/common.c:197
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__sanitizer_cov_trace_pc+0x66/0x70 kernel/kcov.c:235
Code: 82 18 16 00 00 83 f8 02 75 20 48 8b 8a 20 16 00 00 8b 92 1c 16 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 <c3> cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0000:ffffc90003c6f688 EFLAGS: 00000246
RAX: 0000000000080000 RBX: ffff88801f2dd180 RCX: ffffc9000d01d000
RDX: 0000000000080000 RSI: ffffffff823bac59 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888027abf0c0
R13: 0000000000000002 R14: ffff8880591a1980 R15: ffff88807ddfd010
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 __fget_files+0x1d9/0x3c0 fs/file.c:1072
 __fget_light fs/file.c:1173 [inline]
 fdget+0x1a9/0x210 fs/file.c:1181
 class_fd_constructor include/linux/file.h:83 [inline]
 select_poll_one fs/select.c:469 [inline]
 do_select+0xc46/0x17e0 fs/select.c:536
 core_sys_select+0x453/0xc10 fs/select.c:677
 kern_select+0x15d/0x1e0 fs/select.c:718
 __do_sys_select fs/select.c:725 [inline]
 __se_sys_select fs/select.c:722 [inline]
 __x64_sys_select+0xbd/0x160 fs/select.c:722
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f13a2b8ebe9
RSP: 002b:00007f13a0df6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000017
RAX: ffffffffffffffda RBX: 00007f13a2dc6090 RCX: 00007f13a2b8ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000e
RBP: 00007f13a2c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000100 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f13a2dc6128 R14: 00007f13a2dc6090 R15: 00007ffd6ccc46f8
 </TASK>
bridge0: received packet on veth0_to_bridge with own address as source address (addr:42:67:7a:9b:94:d6, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:e4:54:68:d6:6a, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:42:67:7a:9b:94:d6, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:e4:54:68:d6:6a, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/01 01:51 upstream 5c3b3264e585 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in sys_select
* Struck through repros no longer work on HEAD.