Re: 4.14.44: BUG_ON(!list_empty(>wait_list));
On 5 June 2018 at 05:47, wrote: >> -Original Message- >> From: Daniel J Blueman [mailto:dan...@quora.org] >> Sent: Thursday, May 31, 2018 9:21 PM >> To: Linux Kernel; linux-a...@vger.kernel.org >> Cc: Limonciello, Mario; Dominguez, Jared >> Subject: 4.14.44: BUG_ON(!list_empty(>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(>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. Fair suggestion! I can achieve 100% reproducibility of the same backtrace on a clean Ubuntu 18.04 install with 4.17 mainline [1]: 1. disable grub 'quiet' parameter, disconnect charger and power off laptop to S5 2. power on laptop from S5 3. suspend via closing lid 4. resume by opening lid 5. connect LG 27UD88 via USB-C 6. wait 20s 7. disconnect LG 27UD88 8. run 'systemctl poweroff' 9. observe the same backtrace from acpi_os_delete_semaphore I don't observe the issue when using an Apple 87W USB-C Power Adapter, so it may reproduce on other monitors advertising USB-C DisplayPort alternate mode. Thanks, Daniel [1] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.17/linux-image-unsigned-4.17.0-041700-generic_4.17.0-041700.201806041953_amd64.deb >> kernel BUG at /home/kernel/COD/linux/drivers/acpi/osl.c:1201 >> invalid opcode: [#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: 9bc2ab6b9740 task.stack: bOca80034000 >> RIP: 0010:acpi_os_delete_semaphore+0x6d/0x70 >> RSP: 0018:bOca80037be8 EFLAGS: 00010283 >> RAX: bOca83f8fc40 RBX: 9bc238b5dbe0 RCX: >> RDX: 9bc238b5dbe8 RSI: RDI: 9bc238b5dbe0 >> RBP: 9bc2adlc0990 ROB: 9bc2bdc25f20 R09: 9bc29ee56300 >> R10: e03bd2796440 R11: 9bc2ad183fa0 R12: 9bc22f1321e0 >> R13: 0001 R14: 0001 R15: 9bc22f132eb0 >> FS: 7fc03886f940() GS:9bc2bdc0() >> knlGS: >> CS: 0010 DS: ES: CRO: 80050033 >> CR2: 7ffc645e70f8 CR3: 00049e120001 CR4: 003606f0 >> 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:7ffc645e70f8 EFLAGS: 0202 ORIG_RAX: 00a9 >> RAX: ffda RBX: 4321fedc RCX: 7fc03839b373 >> ROX: 4321fedc RSI: 28121969 RDI: fee1dead >> RBP: 7ffc645e7160 R08: R09: >> R10: 0002 R11: 0202 R12: 7ffc645e7168 >> R13: R14: 001b0004 R15: 7ffc645e7458 >> 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 >> 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: b0ca80037be8 -- Daniel J Blueman
Re: 4.14.44: BUG_ON(!list_empty(>wait_list));
On 5 June 2018 at 05:47, wrote: >> -Original Message- >> From: Daniel J Blueman [mailto:dan...@quora.org] >> Sent: Thursday, May 31, 2018 9:21 PM >> To: Linux Kernel; linux-a...@vger.kernel.org >> Cc: Limonciello, Mario; Dominguez, Jared >> Subject: 4.14.44: BUG_ON(!list_empty(>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(>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. Fair suggestion! I can achieve 100% reproducibility of the same backtrace on a clean Ubuntu 18.04 install with 4.17 mainline [1]: 1. disable grub 'quiet' parameter, disconnect charger and power off laptop to S5 2. power on laptop from S5 3. suspend via closing lid 4. resume by opening lid 5. connect LG 27UD88 via USB-C 6. wait 20s 7. disconnect LG 27UD88 8. run 'systemctl poweroff' 9. observe the same backtrace from acpi_os_delete_semaphore I don't observe the issue when using an Apple 87W USB-C Power Adapter, so it may reproduce on other monitors advertising USB-C DisplayPort alternate mode. Thanks, Daniel [1] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.17/linux-image-unsigned-4.17.0-041700-generic_4.17.0-041700.201806041953_amd64.deb >> kernel BUG at /home/kernel/COD/linux/drivers/acpi/osl.c:1201 >> invalid opcode: [#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: 9bc2ab6b9740 task.stack: bOca80034000 >> RIP: 0010:acpi_os_delete_semaphore+0x6d/0x70 >> RSP: 0018:bOca80037be8 EFLAGS: 00010283 >> RAX: bOca83f8fc40 RBX: 9bc238b5dbe0 RCX: >> RDX: 9bc238b5dbe8 RSI: RDI: 9bc238b5dbe0 >> RBP: 9bc2adlc0990 ROB: 9bc2bdc25f20 R09: 9bc29ee56300 >> R10: e03bd2796440 R11: 9bc2ad183fa0 R12: 9bc22f1321e0 >> R13: 0001 R14: 0001 R15: 9bc22f132eb0 >> FS: 7fc03886f940() GS:9bc2bdc0() >> knlGS: >> CS: 0010 DS: ES: CRO: 80050033 >> CR2: 7ffc645e70f8 CR3: 00049e120001 CR4: 003606f0 >> 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:7ffc645e70f8 EFLAGS: 0202 ORIG_RAX: 00a9 >> RAX: ffda RBX: 4321fedc RCX: 7fc03839b373 >> ROX: 4321fedc RSI: 28121969 RDI: fee1dead >> RBP: 7ffc645e7160 R08: R09: >> R10: 0002 R11: 0202 R12: 7ffc645e7168 >> R13: R14: 001b0004 R15: 7ffc645e7458 >> 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 >> 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: b0ca80037be8 -- Daniel J Blueman
RE: 4.14.44: BUG_ON(!list_empty(>wait_list));
> -Original Message- > From: Daniel J Blueman [mailto:dan...@quora.org] > Sent: Thursday, May 31, 2018 9:21 PM > To: Linux Kernel; linux-a...@vger.kernel.org > Cc: Limonciello, Mario; Dominguez, Jared > Subject: 4.14.44: BUG_ON(!list_empty(>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(>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: [#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: 9bc2ab6b9740 task.stack: bOca80034000 > RIP: 0010:acpi_os_delete_semaphore+0x6d/0x70 > RSP: 0018:bOca80037be8 EFLAGS: 00010283 > RAX: bOca83f8fc40 RBX: 9bc238b5dbe0 RCX: > RDX: 9bc238b5dbe8 RSI: RDI: 9bc238b5dbe0 > RBP: 9bc2adlc0990 ROB: 9bc2bdc25f20 R09: 9bc29ee56300 > R10: e03bd2796440 R11: 9bc2ad183fa0 R12: 9bc22f1321e0 > R13: 0001 R14: 0001 R15: 9bc22f132eb0 > FS: 7fc03886f940() GS:9bc2bdc0() > knlGS: > CS: 0010 DS: ES: CRO: 80050033 > CR2: 7ffc645e70f8 CR3: 00049e120001 CR4: 003606f0 > 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:7ffc645e70f8 EFLAGS: 0202 ORIG_RAX: 00a9 > RAX: ffda RBX: 4321fedc RCX: 7fc03839b373 > ROX: 4321fedc RSI: 28121969 RDI: fee1dead > RBP: 7ffc645e7160 R08: R09: > R10: 0002 R11: 0202 R12: 7ffc645e7168 > R13: R14: 001b0004 R15: 7ffc645e7458 > 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 > 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: b0ca80037be8 > -- > Daniel J Blueman
RE: 4.14.44: BUG_ON(!list_empty(>wait_list));
> -Original Message- > From: Daniel J Blueman [mailto:dan...@quora.org] > Sent: Thursday, May 31, 2018 9:21 PM > To: Linux Kernel; linux-a...@vger.kernel.org > Cc: Limonciello, Mario; Dominguez, Jared > Subject: 4.14.44: BUG_ON(!list_empty(>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(>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: [#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: 9bc2ab6b9740 task.stack: bOca80034000 > RIP: 0010:acpi_os_delete_semaphore+0x6d/0x70 > RSP: 0018:bOca80037be8 EFLAGS: 00010283 > RAX: bOca83f8fc40 RBX: 9bc238b5dbe0 RCX: > RDX: 9bc238b5dbe8 RSI: RDI: 9bc238b5dbe0 > RBP: 9bc2adlc0990 ROB: 9bc2bdc25f20 R09: 9bc29ee56300 > R10: e03bd2796440 R11: 9bc2ad183fa0 R12: 9bc22f1321e0 > R13: 0001 R14: 0001 R15: 9bc22f132eb0 > FS: 7fc03886f940() GS:9bc2bdc0() > knlGS: > CS: 0010 DS: ES: CRO: 80050033 > CR2: 7ffc645e70f8 CR3: 00049e120001 CR4: 003606f0 > 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:7ffc645e70f8 EFLAGS: 0202 ORIG_RAX: 00a9 > RAX: ffda RBX: 4321fedc RCX: 7fc03839b373 > ROX: 4321fedc RSI: 28121969 RDI: fee1dead > RBP: 7ffc645e7160 R08: R09: > R10: 0002 R11: 0202 R12: 7ffc645e7168 > R13: R14: 001b0004 R15: 7ffc645e7458 > 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 > 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: b0ca80037be8 > -- > Daniel J Blueman
4.14.44: BUG_ON(!list_empty(>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(>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? Thanks, Daniel -- [1] kernel BUG at /home/kernel/COD/linux/drivers/acpi/osl.c:1201 invalid opcode: [#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: 9bc2ab6b9740 task.stack: bOca80034000 RIP: 0010:acpi_os_delete_semaphore+0x6d/0x70 RSP: 0018:bOca80037be8 EFLAGS: 00010283 RAX: bOca83f8fc40 RBX: 9bc238b5dbe0 RCX: RDX: 9bc238b5dbe8 RSI: RDI: 9bc238b5dbe0 RBP: 9bc2adlc0990 ROB: 9bc2bdc25f20 R09: 9bc29ee56300 R10: e03bd2796440 R11: 9bc2ad183fa0 R12: 9bc22f1321e0 R13: 0001 R14: 0001 R15: 9bc22f132eb0 FS: 7fc03886f940() GS:9bc2bdc0() knlGS: CS: 0010 DS: ES: CRO: 80050033 CR2: 7ffc645e70f8 CR3: 00049e120001 CR4: 003606f0 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:7ffc645e70f8 EFLAGS: 0202 ORIG_RAX: 00a9 RAX: ffda RBX: 4321fedc RCX: 7fc03839b373 ROX: 4321fedc RSI: 28121969 RDI: fee1dead RBP: 7ffc645e7160 R08: R09: R10: 0002 R11: 0202 R12: 7ffc645e7168 R13: R14: 001b0004 R15: 7ffc645e7458 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 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: b0ca80037be8 -- Daniel J Blueman
4.14.44: BUG_ON(!list_empty(>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(>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? Thanks, Daniel -- [1] kernel BUG at /home/kernel/COD/linux/drivers/acpi/osl.c:1201 invalid opcode: [#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: 9bc2ab6b9740 task.stack: bOca80034000 RIP: 0010:acpi_os_delete_semaphore+0x6d/0x70 RSP: 0018:bOca80037be8 EFLAGS: 00010283 RAX: bOca83f8fc40 RBX: 9bc238b5dbe0 RCX: RDX: 9bc238b5dbe8 RSI: RDI: 9bc238b5dbe0 RBP: 9bc2adlc0990 ROB: 9bc2bdc25f20 R09: 9bc29ee56300 R10: e03bd2796440 R11: 9bc2ad183fa0 R12: 9bc22f1321e0 R13: 0001 R14: 0001 R15: 9bc22f132eb0 FS: 7fc03886f940() GS:9bc2bdc0() knlGS: CS: 0010 DS: ES: CRO: 80050033 CR2: 7ffc645e70f8 CR3: 00049e120001 CR4: 003606f0 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:7ffc645e70f8 EFLAGS: 0202 ORIG_RAX: 00a9 RAX: ffda RBX: 4321fedc RCX: 7fc03839b373 ROX: 4321fedc RSI: 28121969 RDI: fee1dead RBP: 7ffc645e7160 R08: R09: R10: 0002 R11: 0202 R12: 7ffc645e7168 R13: R14: 001b0004 R15: 7ffc645e7458 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 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: b0ca80037be8 -- Daniel J Blueman
