Re: Linux v2.6.16

[Peter Williams <pwil3058@bigpond.net.au>]

Ashok Raj wrote:
> On Tue, Mar 21, 2006 at 09:22:41PM -0800, Peter Williams wrote:
> 
>>   I/O APICs
>>   Mar 22 16:10:31 heathwren kernel: More than 8 CPUs detected and
>>   CONFIG_X86_PC cannot handle it.
>>
>>   ###  No more CPUs seen but something in there thinks there's more than
>>   8
>>   of them.
>>
>>   Mar 22 16:10:31 heathwren kernel: Use CONFIG_X86_GENERICARCH or
>>   CONFIG_X86_BIGSMP.
>>
> 
> 
> 
> This was disussed here,  
> 
> http://marc.theaimsgroup.com/?l=linux-kernel&m=114228068804099&w=2
> 
> but we didnt yet close out on it, Andrew didnt feel comfortable
> making CONFIG_HOTPLUG_CPU depend on !X86_PC, and making it depend on CONFIG_GENERICARCH
> or CONFIG_BIGSMP this late in the process.
> 
> The warning is bogus,

That's what I thought but I thought I should still report it as bogus 
messages can cause people to become inured and ignore real ones.

> when BIGSMP was first introduced it was solely to handle >8 CPUS
> using custer mode configuration. We switched bigsmp to use flat physical mode just like 
> what we do for x86_64, because some chipsets have ill effects with cpu hotplug.
> when we wakeup a new cpu. Details here
> 
> http://marc.theaimsgroup.com/?l=linux-kernel&m=113261865814107&w=2
> 
> Hence we switched to bigsmp, but the error message was not reworked, better yet is
> to have the right config depends so we dont run into any race and instability issues.
> 
> 

Peter
-- 
Peter Williams                                   pwil3058@bigpond.net.au

"Learning, n. The kind of ignorance distinguishing the studious."
  -- Ambrose Bierce