Re: [REGRESSION] 41c7f74 rtc: Disable the alarm in the hardware (v2)

[John Stultz]

On 12/01/2013 01:03 PM, Brecht Machiels wrote:
> Hi,
>
> I recently installed (Arch x86_64) Linux with the 3.12.1 kernel on a Toshiba Satellite L300 laptop. After shutting down Linux, the laptop will spontaneously boot up after about five minutes. This seems to be consistent. There are no options in the BIOS for en/disabling or configuring the RTC wakeup alarm. After 'shudown --halt' and shutting down the laptop manually (pressing the power button for 3 seconds), it will not spontaneously boot up. I understand Linux is configuring the RTC alarm on shutdown? 
>
> After finding some other reports of similar problems, I have built a custom 3.12.1 kernel after reverting commit 41c7f74 (rtc: Disable the alarm in the hardware (v2)) [1]. This seems to solve the problem for me.
>
> Related discussions and bug reports:
> * http://thread.gmane.org/gmane.linux.kernel/1527538
>   refers to: https://bugzilla.novell.com/show_bug.cgi?id=812592
>              https://bugzilla.novell.com/show_bug.cgi?id=805740
> * http://thread.gmane.org/gmane.linux.kernel/1275165/focus=1388471
>   refers to: http://bugs.debian.org/691902
>
> Both LKML threads seem to have died without any action being taken.
>
> Setting the RTC alarm time way in the future, as suggested in [2] didn't work for me.
>
> Output of dmidecode is attached. Please let me know if any other information could be useful.
>
> [1] https://github.com/torvalds/linux/commit/41c7f74
> [2] https://forums.computers.toshiba-europe.com/forums/thread.jspa?messageID=256816

Ok, sorry about this. I've been hoping we'd get some better insight into
what's actually happening on these strange BIOSes where disabling the
irq seems to cause it to scream (powering the system back on when its
shutdown), in the hopes of having a proper workaround. But despite
Borislav's efforts, he didn't seem to be able to root cause the issue.

So sadly at this point I guess having the dmi based quirk is the only
reasonable approach. The downside is it will end up killing alarm
functionality on the hardware.

Let me know if the following functions for you (I think I've added the
quirk properly for your system, but am not sure).

Borislav, could you double check this patch still works on your hardware
as well?

thanks
-john