Created attachment 286371 [details] dmesg Since early 5.4 RCs through 5.4.5, I'm seeing this warning which taints the kernel. Happens on every boot. Full dmesg attached. Also reported here but there's no recent status update https://lkml.org/lkml/2019/11/1/678 Dec 19 14:21:16 flap.local kernel: ------------[ cut here ]------------ Dec 19 14:21:16 flap.local kernel: Could not register function stat for cpu 0 Dec 19 14:21:16 flap.local kernel: WARNING: CPU: 2 PID: 1 at kernel/trace/ftrace.c:987 ftrace_init_tracefs_toplevel+0x12d/0x17e Dec 19 14:21:16 flap.local kernel: Modules linked in: Dec 19 14:21:16 flap.local kernel: CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.4.5-300.fc31.x86_64 #1 Dec 19 14:21:16 flap.local kernel: Hardware name: HP HP Spectre Notebook/81A0, BIOS F.43 04/16/2019 Dec 19 14:21:16 flap.local kernel: RIP: 0010:ftrace_init_tracefs_toplevel+0x12d/0x17e Dec 19 14:21:16 flap.local kernel: Code: b9 0e 00 00 00 48 8d 78 20 f3 a5 4c 89 70 20 48 8d 78 20 e8 30 6d 34 fe 85 c0 74 84 89 ee 48 c7 c7 38 75 34 83 e8 ac fc 24 fe <0f> 0b 5b 4c 89 f7 5d 41 5c 41 5d 41 5e e9 0c 16 44 fe 31 c9 49 c7 Dec 19 14:21:16 flap.local kernel: RSP: 0000:ffffb3314007bdf0 EFLAGS: 00010286 Dec 19 14:21:16 flap.local kernel: RAX: 0000000000000000 RBX: ffff97e4f6a00000 RCX: 000000000000029d Dec 19 14:21:16 flap.local kernel: RDX: 0000000000000001 RSI: 0000000000000092 RDI: 0000000000000247 Dec 19 14:21:16 flap.local kernel: RBP: 0000000000000000 R08: 000000000000029d R09: 0000000000000003 Dec 19 14:21:16 flap.local kernel: R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 Dec 19 14:21:16 flap.local kernel: R13: 000000000001c980 R14: ffff97e4f5296380 R15: 0000000000000000 Dec 19 14:21:16 flap.local kernel: FS: 0000000000000000(0000) GS:ffff97e4f6b00000(0000) knlGS:0000000000000000 Dec 19 14:21:16 flap.local kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Dec 19 14:21:16 flap.local kernel: CR2: 0000000000000000 CR3: 000000028f60a001 CR4: 00000000003606e0 Dec 19 14:21:16 flap.local kernel: Call Trace: Dec 19 14:21:16 flap.local kernel: tracer_init_tracefs+0x8c/0x1e7 Dec 19 14:21:16 flap.local kernel: ? register_tracer+0x1bc/0x1bc Dec 19 14:21:16 flap.local kernel: do_one_initcall+0x46/0x1f4 Dec 19 14:21:16 flap.local kernel: kernel_init_freeable+0x1a7/0x24e Dec 19 14:21:16 flap.local kernel: ? rest_init+0xaa/0xaa Dec 19 14:21:16 flap.local kernel: kernel_init+0xa/0x106 Dec 19 14:21:16 flap.local kernel: ret_from_fork+0x35/0x40 Dec 19 14:21:16 flap.local kernel: ---[ end trace 8653078ac364f7e6 ]--- Dec 19 14:21:16 flap.local kernel: Lockdown: swapper/0: use of tracefs is restricted; see man kernel_lockdown.7 Dec 19 14:21:16 flap.local kernel: Could not create tracefs 'tracing_thresh' entry Dec 19 14:21:16 flap.local kernel: Lockdown: swapper/0: use of tracefs is restricted; see man kernel_lockdown.7 Dec 19 14:21:16 flap.local kernel: Could not create tracefs 'README' entry Dec 19 14:21:16 flap.local kernel: Lockdown: swapper/0: use of tracefs is restricted; see man kernel_lockdown.7 Dec 19 14:21:16 flap.local kernel: Could not create tracefs 'saved_cmdlines' entry Dec 19 14:21:16 flap.local kernel: Lockdown: swapper/0: use of tracefs is restricted; see man kernel_lockdown.7 Dec 19 14:21:16 flap.local kernel: Could not create tracefs 'saved_cmdlines_size' entry Dec 19 14:21:16 flap.local kernel: Lockdown: swapper/0: use of tracefs is restricted; see man kernel_lockdown.7 Dec 19 14:21:16 flap.local kernel: Could not create tracefs 'saved_tgids' entry Dec 19 14:21:16 flap.local kernel: Lockdown: swapper/0: use of tracefs is restricted; see man kernel_lockdown.7 Dec 19 14:21:16 flap.local kernel: Could not create tracefs 'eval_map' entry Dec 19 14:21:16 flap.local kernel: Lockdown: swapper/0: use of tracefs is restricted; see man kernel_lockdown.7 Dec 19 14:21:16 flap.local kernel: Could not create tracefs 'dyn_ftrace_total_info' entry Dec 19 14:21:16 flap.local kernel: Lockdown: swapper/0: use of tracefs is restricted; see man kernel_lockdown.7 Dec 19 14:21:16 flap.local kernel: Could not create tracefs 'funcgraph-overrun' entry Dec 19 14:21:16 flap.local kernel: ------------[ cut here ]------------ Dec 19 14:21:16 flap.local kernel: Failed to create trace option: funcgraph-overrun Dec 19 14:21:16 flap.local kernel: WARNING: CPU: 2 PID: 1 at kernel/trace/trace.c:8106 create_trace_option_files+0x1ef/0x220 Dec 19 14:21:16 flap.local kernel: Modules linked in: Dec 19 14:21:16 flap.local kernel: CPU: 2 PID: 1 Comm: swapper/0 Tainted: G W 5.4.5-300.fc31.x86_64 #1 Dec 19 14:21:16 flap.local kernel: Hardware name: HP HP Spectre Notebook/81A0, BIOS F.43 04/16/2019 Dec 19 14:21:16 flap.local kernel: RIP: 0010:create_trace_option_files+0x1ef/0x220 Dec 19 14:21:16 flap.local kernel: Code: 48 85 c0 75 96 48 8b 43 18 eb b6 80 3d fb ed 61 01 00 75 b2 49 8b 37 48 c7 c7 a8 8b 34 83 c6 05 e8 ed 61 01 01 e8 9f c4 f0 ff <0f> 0b eb 98 bf 20 00 00 00 e9 da fe ff ff 48 8b 3c 24 48 83 c4 08 Dec 19 14:21:16 flap.local kernel: RSP: 0000:ffffb3314007bdc8 EFLAGS: 00010282 Dec 19 14:21:16 flap.local kernel: RAX: 0000000000000000 RBX: ffff97e4f4966400 RCX: 0000000000000000 Dec 19 14:21:16 flap.local kernel: RDX: 0000000000000030 RSI: ffffffff84126570 RDI: 0000000000000246 Dec 19 14:21:16 flap.local kernel: RBP: ffffffff836cfc20 R08: 000000001dc435ad R09: 0000000000000030 Dec 19 14:21:16 flap.local kernel: R10: ffffffff84126920 R11: 000000008412655e R12: ffffffff836d21c0 Dec 19 14:21:16 flap.local kernel: R13: ffffffff836d21e0 R14: 0000000000000000 R15: ffffffff836d21e0 Dec 19 14:21:16 flap.local kernel: FS: 0000000000000000(0000) GS:ffff97e4f6b00000(0000) knlGS:0000000000000000 Dec 19 14:21:16 flap.local kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Dec 19 14:21:16 flap.local kernel: CR2: 0000000000000000 CR3: 000000028f60a001 CR4: 00000000003606e0 Dec 19 14:21:16 flap.local kernel: Call Trace: Dec 19 14:21:16 flap.local kernel: __update_tracer_options+0x26/0x40 Dec 19 14:21:16 flap.local kernel: tracer_init_tracefs+0x1d6/0x1e7 Dec 19 14:21:16 flap.local kernel: ? register_tracer+0x1bc/0x1bc Dec 19 14:21:16 flap.local kernel: do_one_initcall+0x46/0x1f4 Dec 19 14:21:16 flap.local kernel: kernel_init_freeable+0x1a7/0x24e Dec 19 14:21:16 flap.local kernel: ? rest_init+0xaa/0xaa Dec 19 14:21:16 flap.local kernel: kernel_init+0xa/0x106 Dec 19 14:21:16 flap.local kernel: ret_from_fork+0x35/0x40 Dec 19 14:21:16 flap.local kernel: ---[ end trace 8653078ac364f7e7 ]---
I'm not seeing this in 5.5 rc1 or rc2
Should be fixed by commit: a356646a56857c2e5ad875beec734d7145ecd49a ("tracing: Do not create directories if lockdown is in affect")
It's not in 5.4.5, and I don't see that it's been sent to linux-stable@.
No, but the stable team is usually good at picking up patches with the Fixes tag in them.
The fix has now been added to the 5.4 queue.