[lkml]   [2006]   [Jul]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
SubjectRe: 2.6.17 -> 2.6.18 regression: cpufreq broken since 2.6.18-rc1 on pentium4
On Sun, Jul 30, 2006 at 03:01:33PM -0400, Dave Jones wrote:

> Normally, if the necessary BIOS bits aren't there, then acpi-cpufreq will
> fail to register. For some reason it sounds like it believes that everything
> went ok. I wonder if something changed in acpi recently that caused this
> change in behaviour ? Len ?

As far as I can see, acpi_cpufreq does not pass on any errors it sees during

static int __init acpi_cpufreq_init (void)
int result = 0;


result = acpi_cpufreq_early_init_acpi();

And from acpi_cpufreq_early_init_acpi():

static int acpi_cpufreq_early_init_acpi(void)
struct acpi_processor_performance *data;
unsigned int i, j;


( some memory allocations, does not look at acpi or bios )

/* Do initialization in ACPI core */
return 0;

Note how any error from acpi_processor_preregister_performance is ignored.

Ghetto patch which "fixes" the problem for me:

--- ./arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c~orig 2006-07-30 21:14:43.000000000 +0200
+++ ./arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c 2006-07-30 21:11:34.000000000 +0200
@@ -384,8 +384,7 @@

/* Do initialization in ACPI core */
- acpi_processor_preregister_performance(acpi_perf_data);
- return 0;
+ return acpi_processor_preregister_performance(acpi_perf_data);

But tonight I have no speedstep laptop available to check if this does not
kill acpi_cpufreq when it can work.
Thanks for the hint, dave!

-- Open source, database driven DNS Software Open and Closed source services
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2006-07-30 21:23    [W:0.212 / U:2.780 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site