RE: 4.14.44: BUG_ON(!list_empty(&sem->wait_list));

[Mario.Limonciello]

> -----Original Message-----
> From: Daniel J Blueman [mailto:daniel@xxxxxxxxx]
> Sent: Thursday, May 31, 2018 9:21 PM
> To: Linux Kernel; linux-acpi@xxxxxxxxxxxxxxx
> Cc: Limonciello, Mario; Dominguez, Jared
> Subject: 4.14.44: BUG_ON(!list_empty(&sem->wait_list));
> 
> Plugging in a USB-C power source on my Dell XPS 9550 trips an ACPI
> BUG_ON [1], reproducible with mainline 4.14.44, suggesting other
> threads are waiting for semaphore acquisition due to
> "BUG_ON(!list_empty(&sem->wait_list))".
> 
> This is the current 1.7.0 BIOS with Ubuntu 18.04 userspace, plugging
> in an LG 27UD88 (also with the current firmware) monitor USB-C
> connection which apparently advertises 60W charging (x1,
> PowerDelivery, DisplayPort alternative mode, data). The same issues
> reproduce on a Dell Precision 5510 with Ubuntu 16.04, the shipped
> kernel and 4.14.44.
> 
> I can enable ACPI debugging if useful? Perhaps ACPI_DB_MUTEX or other
> levels would be appropriate?

I think most useful would be if this can still reproduce with 4.17.

> 
> Thanks,
>   Daniel
> 
> -- [1]
> 
> kernel BUG at /home/kernel/COD/linux/drivers/acpi/osl.c:1201
> invalid opcode: 0000 [#1] SMP PTI
> Modules linked in: [...]
> CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted 4.14.44-041444-generic
> #201805251612
> Hardware name: Dell Inc. XPS 15 9550/, BIOS 1.7.0 02/23/2018
> task: ffff9bc2ab6b9740 task.stack: ffffbOca80034000
> RIP: 0010:acpi_os_delete_semaphore+0x6d/0x70
> RSP: 0018:ffffbOca80037be8 EFLAGS: 00010283
> RAX: ffffbOca83f8fc40 RBX: ffff9bc238b5dbe0 RCX: 0000000000000000
> RDX: ffff9bc238b5dbe8 RSI: 0000000000000000 RDI: ffff9bc238b5dbe0
> RBP: ffff9bc2adlc0990 ROB: ffff9bc2bdc25f20 R09: ffff9bc29ee56300
> R10: ffffe03bd2796440 R11: ffff9bc2ad183fa0 R12: ffff9bc22f1321e0
> R13: 0000000000000001 R14: 0000000000000001 R15: ffff9bc22f132eb0
> FS: 00007fc03886f940(0000) GS:ffff9bc2bdc00000(0000)
> knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CRO: 0000000080050033
> CR2: 00007ffc645e70f8 CR3: 000000049e120001 CR4: 00000000003606f0
> Call Trace:
> acpi_ex_system_reset_event+0x3f/0x65
> acpi_ex_opcode_1A_OT_0R+0x70/0xfa
> acpi_ds_exec_end_op+0x15d/0x71b
> acpi_ps_parse_loop+0x929/0x9d6
> ? acpi_ds_result_push+0x82/0x1d2
> acpi_ps_parse_aml+0x1a2/0x4af
> acpi_ps_execute_method+0x1ef/0x2ab
> acpi_ns_evaluate+0x2e4/0x41d
> acpi_evaluate_object+0x1cb/0x38e
> acpi_enter_sleep_state_prep+0xae/0x13a
> acpi_sleep_prepare.part.2+0x2e/0x40
> acpi_power_off_prepare+0xf/0x20
> [38871.1925361 kernel_power_off+0x42/0x70
> SYSC_reboot+0x12f/0x210
> ? handle_mm_fault+0xea/0x1e0
> [38871.1925861 ? do_writev+0x5e/0xf0
> ? do_writev+0x5e/0xf0
> do_syscall_64+0x6e/0x120
> entry_SYSCALL_64_after_hwframe+0x3d/0xa2
> RIP: 0033:0x7fc03839b373
> RSP: 002b:00007ffc645e70f8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a9
> RAX: ffffffffffffffda RBX: 000000004321fedc RCX: 00007fc03839b373
> ROX: 000000004321fedc RSI: 0000000028121969 RDI: 00000000fee1dead
> RBP: 00007ffc645e7160 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000002 R11: 0000000000000202 R12: 00007ffc645e7168
> R13: 0000000000000000 R14: 0000001b00000004 R15: 00007ffc645e7458
> Code: b8 00 04 00 00 48 c7 c1 c3 91 28 ab 48 c7 c2 20 91 28 ab be of
> 04 00 00 bf 00 00 00 01 03 41 85 04 00 58 eb b0 b8 01 10 00 00 c3 <Of>
> Ob 90 Of if 44 00 00 80 3d 74 CO 97 01 00 41 54 55 53 Of 84
> RIP: acpi_os_delete_semaphore+0x6d/0x70 RSP: ffffb0ca80037be8
> --
> Daniel J Blueman