On 2020-07-14 17:53:15 [+0200], Rafael J. Wysocki wrote: > acpi_evaluate_integer() doesn't show up in the trace, though, AFAICS. > > > I assumed acpi_ex_opcode_2A_0T_0R() since the other > > candidate was acpi_ev_asynch_execute_gpe_method(). > > Which probably is the case. Specifically > > acpi_ev_asynch_execute_gpe_method: Evaluate _L66 > > is likely to cause the Notify() to be dispatched. … > > Rafael, are you also interested in an ACPI dump? > > That might help a bit. > > So what probably happens is that poking at the TZ causes a GPE to > trigger and a Notify() to be dispatched which then goes into the > workqueue for execution. > > Now, I'm not sure what happens to those Notify() items, though. They > each should cause a handler (in the thermal driver) to be executed, > but does that happen? Stephen's trace contains a few backtraces, all of them look like this: | Call Trace: | acpi_ex_opcode_2A_0T_0R+0x93/0xdf | acpi_ds_exec_end_op+0x10d/0x701 | acpi_ps_parse_loop+0x7f2/0x8c3 | acpi_ps_parse_aml+0x1a5/0x540 | acpi_ps_execute_method+0x1fe/0x2ba | acpi_ns_evaluate+0x345/0x4e2 | acpi_evaluate_object+0x177/0x39f | acpi_evaluate_integer+0x4f/0x110 | acpi_thermal_get_temperature.part.0+0x45/0xc4 | thermal_get_temp.cold+0xc/0x2e | thermal_zone_get_temp+0x4c/0x70 | thermal_zone_device_update.part.0+0x2a/0x110 | acpi_thermal_notify+0xcf/0x140 | acpi_ev_notify_dispatch+0x45/0x5a | acpi_os_execute_deferred_notify+0x34/0x60 | process_one_work+0x1d2/0x3a0 | worker_thread+0x45/0x3c0 | kthread+0xf6/0x130 | ret_from_fork+0x35/0x40 so no GPE and it comes the notify callback while parsing the ACPI table. Any ideas? I guess acpi_ex_opcode_2A_0T_0R() uses the workqueue because it may sleep and it might be invoked from non-preemptible context. Sebastian
