2.6.24.3 SMP kernel sees only one of my 2 cores..

[Roger Heflin]

Gautam Thaker wrote:
> I am running Fedora Core 8 w/ all the updates installed. The kernel
> version is 2.6.24.3-34.fc8 SMP. I  have been using the system happily
> for about 2 months. I don't know just when, but in last week, the
> kernel sees only  1 of my 2 cores. I know i have run quite some time
> w/ 2 cores. I am not sure if this is related to some SW update or a
> bios problem (i loaded "defaults" in bios) or can the CPU actually
> break and be left w/ just 1 core?  I do see a msg at start up, at very
> start, that says:
> 
> i8042c: can not read CTR when initializing i8042.
> 
> Can this be related to my problem? Any hints welcome, I tried lots of
> google search but did not find anything related.
> 
> Gautam
> 
> 
> [root at zadapi-L gthaker]# more /proc/cpuinfo
> processor       : 0
> vendor_id       : AuthenticAMD
> cpu family      : 15
> model           : 107
> model name      : AMD Athlon(tm) 64 X2 Dual Core Processor 4000+
> stepping        : 1
> cpu MHz         : 1000.000
> cache size      : 512 KB
> physical id     : 0
> siblings        : 1
> core id         : 0
> cpu cores       : 1
> fdiv_bug        : no
> hlt_bug         : no
> f00f_bug        : no
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 1
> wp              : yes
> flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca
> cmov pat
> pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt rdtscp
> lm 3dnowext
>  3dnow pni cx16 lahf_lm cmp_legacy svm extapic cr8_legacy misalignsse
> ts fid vid
>  ttp tm stc 100mhzsteps
> bogomips        : 2010.70
> clflush size    : 64
> 
> THERE SHOULD BE 1 MORE PROCESSOR....!
> 

Check the bios settings, someone else lost most of his cores and traced it back 
to a bios setting that caused the cpus to not be seen in some version of the 
kernel.

He had disabled CPUID LIMIT in the bios and cpus disappeared in some kernel 
versions, see if yours is enabled or disabled.

Also a number of other bios settings will cause cpus to disappear.

                            Roger