On Friday, 26 of September 2008, Zhao, Yakui wrote: > Alan gives a suggestion that after processing the EC notification event, EC driver > should continue to issue the query command and process the EC notification > event until the query command returns zero. > But this suggestion will break my laptop. On my laptop when issuing the query > command, a non-zero query event is returned but it can't be processed.(There > is no corresponding ACPI _Qxx object). At the same time the SCI_EVT bit won't > be cleared. In such case OS can't exit the function of acpi_ec_query_handler, > which causes that the acpid kernel thread can't work well. Well, perhaps we should exit acpi_ec_query_handler() if SCI_EVT is clear _or_ the processing of an event fails due to the lack of a _Qxx object? Alex? > In fact according to my analysis IMO Alexey's patch will break my laptop. That obviously would be a regression. > But now the laptop is not in my hand and I can't do the test. After I own the > laptop again, I will do the test and attach the corresponding info. OK, how much time is it going to take, approximately? > At the same time there are two generic issues in this patch: > a. spin_lock is overkill. When 2000 EC I/O read/write are executed, the > CPU interrupt will be disabled for about 1.5ms. This will affect the normal > laptops. OTOH, I think we need _some_ locking in there in order to prevent races from happening. > b. the local variable that resides in process stack space is used in > interrupt-context. Which one? Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
