Bug 15366

Created attachment 25149 [details]
[PATCH] Make sure curr_clocksource gets initialized 

Ugh. Yea, looks like the clocksource rework missed this. 

Here's a test patch that tries to avoid the value being uninitialized. I've not tested it, but let me know if it doesn't resolve the issue.

thanks
-john

(In reply to comment #1)
> Created an attachment (id=25149) [details]
> [PATCH] Make sure curr_clocksource gets initialized 
> 
> Ugh. Yea, looks like the clocksource rework missed this. 
> 
> Here's a test patch that tries to avoid the value being uninitialized. I've
> not
> tested it, but let me know if it doesn't resolve the issue.

In practice that patch would work, but it will introduce section mismatch warnings:

  CC      kernel/time/clocksource.o
  LD      kernel/time/built-in.o
WARNING: kernel/time/built-in.o(.text+0x1c04): Section mismatch in reference from the function clocksource_unregister() to the function .init.text:clocksource_default_clock()
The function clocksource_unregister() references
the function __init clocksource_default_clock().
This is often because clocksource_unregister lacks a __init
annotation or the annotation of clocksource_default_clock is wrong.

WARNING: kernel/time/built-in.o(.text+0x1c68): Section mismatch in reference from the function __clocksource_change_rating() to the function .init.text:clocksource_default_clock()
The function __clocksource_change_rating() references
the function __init clocksource_default_clock().
This is often because __clocksource_change_rating lacks a __init
annotation or the annotation of clocksource_default_clock is wrong.

WARNING: kernel/time/built-in.o(.text+0x1e1c): Section mismatch in reference from the function sysfs_override_clocksource() to the function .init.text:clocksource_default_clock()
The function sysfs_override_clocksource() references
the function __init clocksource_default_clock().
This is often because sysfs_override_clocksource lacks a __init
annotation or the annotation of clocksource_default_clock is wrong.

WARNING: kernel/time/built-in.o(.text+0x1f10): Section mismatch in reference from the function clocksource_register() to the function .init.text:clocksource_default_clock()
The function clocksource_register() references
the function __init clocksource_default_clock().
This is often because clocksource_register lacks a __init
annotation or the annotation of clocksource_default_clock is wrong.

Created attachment 25166 [details]
Second attempt at getting curr_clocksource initialized

Thanks for the testing and sorry it wasn't right. Here's another attempt to make sure curr_clocksource is set. Build but not boot tested.

thanks
-john

(In reply to comment #3)
> Created an attachment (id=25166) [details]
> Second attempt at getting curr_clocksource initialized
> 
> Thanks for the testing and sorry it wasn't right. Here's another attempt to
> make sure curr_clocksource is set. Build but not boot tested.

This patch does not have build issues, and even better, my computer does not oops anymore:

# cat /sys/devices/system/clocksource/clocksource0/current_clocksource
jiffies

Thanks. I hope the fix will end up in stable tree (2.6.32.x).

Aaro, thanks for testing! I'll push this to 2.6.33.x and 2.6.32.x today.

Patch is upstream.