Hello,
kernel test robot noticed "WARNING:suspicious_RCU_usage" on:
commit: bf652e038501425f21e30c78c210ce892b9747c5 ("[RFC PATCH bpf-next v2 1/9] cgroup: Make operations on the cgroup root_list RCU safe")
url: https://github.com/intel-lab-lkp/linux/commits/Yafang-Shao/cgroup-Make-operations-on-the-cgroup-root_list-RCU-safe/20231017-204729
base: https://git.kernel.org/cgit/linux/kernel/git/bpf/bpf-next.git master
patch link: https://lore.kernel.org/all/20231017124546.24608-2-laoar.shao@xxxxxxxxx/
patch subject: [RFC PATCH bpf-next v2 1/9] cgroup: Make operations on the cgroup root_list RCU safe
in testcase: boot
compiler: gcc-12
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G
(please refer to attached dmesg/kmsg for entire log/backtrace)
+------------------------------------------------------------------+------------+------------+
| | 137df1189d | bf652e0385 |
+------------------------------------------------------------------+------------+------------+
| WARNING:suspicious_RCU_usage | 0 | 6 |
| kernel/cgroup/cgroup#c:#RCU-list_traversed_in_non-reader_section | 0 | 6 |
+------------------------------------------------------------------+------------+------------+
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-lkp/202310251500.9683d034-oliver.sang@xxxxxxxxx
[ 245.792697][ T1] WARNING: suspicious RCU usage
[ 245.793945][ T1] 6.6.0-rc5-01395-gbf652e038501 #1 Not tainted
[ 245.795294][ T1] -----------------------------
[ 245.796458][ T1] kernel/cgroup/cgroup-v1.c:1171 RCU-list traversed in non-reader section!!
[ 245.798005][ T1]
[ 245.798005][ T1] other info that might help us debug this:
[ 245.798005][ T1]
[ 245.800905][ T1]
[ 245.800905][ T1] rcu_scheduler_active = 2, debug_locks = 1
[ 245.815563][ T1] 1 lock held by init/1:
[ 245.816666][ T1] #0: c3bfffb8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock_and_drain_offline (kernel/cgroup/cgroup.c:3066)
[ 245.818306][ T1]
[ 245.818306][ T1] stack backtrace:
[ 245.820360][ T1] CPU: 0 PID: 1 Comm: init Not tainted 6.6.0-rc5-01395-gbf652e038501 #1
[ 245.821860][ T1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
[ 245.823506][ T1] Call Trace:
[ 245.824459][ T1] dump_stack_lvl (lib/dump_stack.c:107)
[ 245.825654][ T1] dump_stack (lib/dump_stack.c:114)
[ 245.826665][ T1] lockdep_rcu_suspicious (include/linux/context_tracking.h:153 kernel/locking/lockdep.c:6712)
[ 245.827845][ T1] cgroup1_root_to_use (kernel/cgroup/cgroup-v1.c:1171 (discriminator 9))
[ 245.828999][ T1] cgroup1_get_tree (kernel/cgroup/cgroup-v1.c:1245)
[ 245.830101][ T1] vfs_get_tree (fs/super.c:1750)
[ 245.831172][ T1] do_new_mount (fs/namespace.c:3335)
[ 245.832199][ T1] path_mount (fs/namespace.c:3662)
[ 245.833147][ T1] ? user_path_at_empty (fs/namei.c:2914)
[ 245.834198][ T1] __ia32_sys_mount (fs/namespace.c:3675 fs/namespace.c:3884 fs/namespace.c:3861 fs/namespace.c:3861)
[ 245.835242][ T1] do_int80_syscall_32 (arch/x86/entry/common.c:112 arch/x86/entry/common.c:132)
[ 245.836343][ T1] ? kfree (mm/slab_common.c:1073)
[ 245.837335][ T1] ? __ia32_sys_mount (fs/namespace.c:3861)
[ 245.838404][ T1] ? do_int80_syscall_32 (arch/x86/entry/common.c:136)
[ 245.839479][ T1] ? syscall_exit_to_user_mode (kernel/entry/common.c:131 kernel/entry/common.c:298)
[ 245.840593][ T1] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4565)
[ 245.841824][ T1] ? syscall_exit_to_user_mode (kernel/entry/common.c:299)
[ 245.842967][ T1] ? do_int80_syscall_32 (arch/x86/entry/common.c:136)
[ 245.843964][ T1] ? __ia32_sys_mount (fs/namespace.c:3861)
[ 245.844935][ T1] ? do_int80_syscall_32 (arch/x86/entry/common.c:136)
[ 245.845958][ T1] ? syscall_exit_to_user_mode (kernel/entry/common.c:131 kernel/entry/common.c:298)
[ 245.847004][ T1] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4565)
[ 245.848103][ T1] ? syscall_exit_to_user_mode (kernel/entry/common.c:299)
[ 245.849159][ T1] ? do_int80_syscall_32 (arch/x86/entry/common.c:136)
[ 245.850163][ T1] ? syscall_exit_to_user_mode (kernel/entry/common.c:299)
[ 245.851209][ T1] ? do_int80_syscall_32 (arch/x86/entry/common.c:136)
[ 245.852179][ T1] ? lock_release (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5775)
[ 245.853126][ T1] ? irqentry_exit (kernel/entry/common.c:445)
[ 245.858431][ T1] ? irqentry_exit_to_user_mode (kernel/entry/common.c:131 kernel/entry/common.c:311)
[ 245.859731][ T1] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4565)
[ 245.860985][ T1] ? irqentry_exit_to_user_mode (kernel/entry/common.c:312)
[ 245.862110][ T1] ? irqentry_exit (kernel/entry/common.c:445)
[ 245.863099][ T1] ? exc_page_fault (arch/x86/mm/fault.c:1565)
[ 245.864073][ T1] entry_INT80_32 (arch/x86/entry/entry_32.S:947)
[ 245.865070][ T1] EIP: 0xb7f895ed
[ 245.865966][ T1] Code: 8b 7c 24 0c 50 e8 06 00 00 00 89 da 5b 5b 5f c3 8b 04 24 05 77 ec 04 00 8b 00 85 c0 74 06 50 8b 44 24 08 c3 8b 44 24 04 cd 80 <c3> 55 50 8b 6c 24 0c 8b 45 00 8b 6d 04 50 8b 44 24 04 e8 b9 ff ff
All code
========
0: 8b 7c 24 0c mov 0xc(%rsp),%edi
4: 50 push %rax
5: e8 06 00 00 00 call 0x10
a: 89 da mov %ebx,%edx
c: 5b pop %rbx
d: 5b pop %rbx
e: 5f pop %rdi
f: c3 ret
10: 8b 04 24 mov (%rsp),%eax
13: 05 77 ec 04 00 add $0x4ec77,%eax
18: 8b 00 mov (%rax),%eax
1a: 85 c0 test %eax,%eax
1c: 74 06 je 0x24
1e: 50 push %rax
1f: 8b 44 24 08 mov 0x8(%rsp),%eax
23: c3 ret
24: 8b 44 24 04 mov 0x4(%rsp),%eax
28: cd 80 int $0x80
2a:* c3 ret <-- trapping instruction
2b: 55 push %rbp
2c: 50 push %rax
2d: 8b 6c 24 0c mov 0xc(%rsp),%ebp
31: 8b 45 00 mov 0x0(%rbp),%eax
34: 8b 6d 04 mov 0x4(%rbp),%ebp
37: 50 push %rax
38: 8b 44 24 04 mov 0x4(%rsp),%eax
3c: e8 .byte 0xe8
3d: b9 .byte 0xb9
3e: ff (bad)
3f: ff .byte 0xff
Code starting with the faulting instruction
===========================================
0: c3 ret
1: 55 push %rbp
2: 50 push %rax
3: 8b 6c 24 0c mov 0xc(%rsp),%ebp
7: 8b 45 00 mov 0x0(%rbp),%eax
a: 8b 6d 04 mov 0x4(%rbp),%ebp
d: 50 push %rax
e: 8b 44 24 04 mov 0x4(%rsp),%eax
12: e8 .byte 0xe8
13: b9 .byte 0xb9
14: ff (bad)
15: ff .byte 0xff
[ 245.868936][ T1] EAX: ffffffda EBX: 0804a431 ECX: 0804a429 EDX: 0804a431
[ 245.870279][ T1] ESI: 0000000e EDI: 00000000 EBP: bffa7bd8 ESP: bffa7bb8
[ 245.871623][ T1] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00000246
[ 245.935209][ T1] init: Console is alive
The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20231025/202310251500.9683d034-oliver.sang@xxxxxxxxx
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
