Athlon X2 Dual Core Processor - Second CPU/Core not working with i386 kernel

Thank you for taking the time to report this bug and helping to make Ubuntu better. This bug did not have a package associated with it, which is important for ensuring that it gets looked at by the proper developers. You can learn more about finding the right package at https://wiki.ubuntu.com/Bugs/FindRightPackage . I have classified this bug as a bug in linux the kernel for Hardy Heron.

Thank you for taking the time to report this bug and helping to make Ubuntu better. Unfortunately we can't fix it, because your description doesn't yet have enough information.
Please include as attachments the following additional information (when booting an i386 Live CD), if you have not already done so (please pay attention to lspci's additional options), as required by the Ubuntu Kernel Team:
1. Please include the output of the command 'uname -a' in your next response. It should be one, long line of text which includes the exact kernel version you're running, as well as the CPU architecture.
2. Please run the command 'dmesg > dmesg.log' and attach the resulting file 'dmesg.log' to this bug report.
3. Please run the command 'sudo lspci -vvnn > lspci-vvnn.log' and attach the resulting file 'lspci-vvnn.log' to this bug report.
For your reference, the full description of procedures for kernel-related bug reports is available at https://wiki.ubuntu.com/KernelTeamBugPolicies . Thanks in advance!

Hi, I have encountered the same problem when using Hardy Heron 32 bit, only 1-core is getting activated. While using 64 bit successfully activates 2-cores of my AMD AthlonX2 5600 processor..

I hope this would help:

Output of "uname -a":
Linux ubuntu 2.6.24-12-generic #1 SMP Wed Mar 12 23:01:54 UTC 2008 i686 GNU/Linux

Additionally, I've attached 2 log files as requested.

Regards,

Hadji

Hello, here is the requested info after booting Ubuntu Hardy 8.04 Beta LiveCD for i386:

$uname -a
Linux ubuntu 2.6.24-12-generic #1 SMP Wed Mar 12 23:01:54 UTC 2008 i686 GNU/Linux

Attached files
* dmesg.log
* lspci-vvnn.log
* cpuinfo.log

Hi Brian,

If you are still keen to check on this, we've posted couple of files you've requsted.

Let us know of any progress.

Cheers,

Hadji

I confirm the problem is still there with latest kernel (uname -a):

Linux l5100 2.6.24-16-generic #1 SMP Thu Apr 10 13:23:42 UTC 2008 i686 GNU/Linux

For what it's worth...

I tried to reproduce this problem by booting the Hardy i386 Live Desktop cd on each of my AMD x2 machines. Once the live CD was up and running, I examined /proc/cpuinfo looking for only one core.

I was NOT able to reproduce this problem on the following CPU's:
1) AMD Athlon(tm) 64 X2 Dual Core Processor 3800+
2) AMD Athlon(tm) 64 X2 Dual Core Processor 4000+
3) AMD Athlon(tm) 64 X2 Dual Core Processor 4400+
4) AMD Athlon(tm) 64 X2 Dual Core Processor 4600+
5) AMD Athlon(tm) 64 X2 Dual Core Processor 5600+

Although I have 5 different CPU's, I only have 2 different motherboards, both Nvidia chipsets.

This leads me to believe that this might be a particular to your motherboard? Perhaps a BIOS setting?

What is the motherboard manufacturer and model where these problems are occurring?

:-Dustin

The hardware is a slimline PC sold here as Acer L5100.
I think it contains a bunch of components normally used in laptops
and according to the lspci output (see attachments above)
it uses some AMD/ATI "IO"-chipset(s).

As everything works fine with a amd64/x86_64 kernel I do not like
the idea of messing around with BIOS settings (I haven't seen any
obvious settings related to the CPU problem).

I found a german ubuntu forum meanwhile where someone documented
the same problem with the same hardware.

[ I also compiled 2.6.25 myself to check the new kernel but I failed to
  repackage a working initrd based on the 2.6.24 initrd of ubuntu ...
  So I'm eagerly waiting for Fedora 9 with 2.6.25 kernel for further tests ... ]

Erik

Hello, I've the same bug, with kernel amd64 2xcpu, but with 386 SMP only one cpu.
The computer was an ACER L5100

dmidecode partial

System Information
        Manufacturer: Acer
        Product Name: AL 5100 / VL410
        Version: R01-B0 <------ LASTEST BIOS
        Serial Number:
        UUID: 00000000-0000-0000-0807-060504030201
        Wake-up Type: Power Switch
        SKU Number:
        Family:

Handle 0x0002, DMI type 2, 14 bytes
Base Board Information
        Manufacturer: Acer
        Product Name: FRS690L
        Version:
        Serial Number:

------------
Processor Information
        Socket Designation: Socket AM2
        Type: Central Processor
        Family: Athlon 64 X2
        Manufacturer: AMD
        ID: B1 0F 06 00 FF FB 8B 17
        Signature: Family 15, Model 107, Stepping 1
        Flags:
                FPU (Floating-point unit on-chip)
                VME (Virtual mode extension)
                DE (Debugging extension)
                PSE (Page size extension)
                TSC (Time stamp counter)
                MSR (Model specific registers)
                PAE (Physical address extension)
                MCE (Machine check exception)
                CX8 (CMPXCHG8 instruction supported)
                APIC (On-chip APIC hardware supported)
                SEP (Fast system call)
                MTRR (Memory type range registers)
                PGE (Page global enable)
                MCA (Machine check architecture)
                CMOV (Conditional move instruction supported)
                PAT (Page attribute table)
                PSE-36 (36-bit page size extension)
                CLFSH (CLFLUSH instruction supported)
                MMX (MMX technology supported)
                FXSR (Fast floating-point save and restore)
                SSE (Streaming SIMD extensions)
                SSE2 (Streaming SIMD extensions 2)
                HTT (Hyper-threading technology)
        Version: AMD Athlon(tm) 64 X2 Dual Core Processor 5000+
        Voltage: 1.3 V
        External Clock: 199 MHz
        Max Speed: 3000 MHz
        Current Speed: 2587 MHz
        Status: Populated, Enabled
        Upgrade: Socket 940
        L1 Cache Handle: 0x0008
        L2 Cache Handle: 0x0009
        L3 Cache Handle: Not Provided
        Serial Number:
        Asset Tag:
        Part Number:
        Core Count: 2
        Core Enabled: 2
        Thread Count: 2
        Characteristics:
                64-bit capable

 #uname -a
Linux XXXXXXXXXX 2.6.22-14-generic #1 SMP Tue Feb 12 07:42:25 UTC 2008 i686 GNU/Linux

# cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 107
model name : AMD Athlon(tm) 64 X2 Dual Core Processor 5000+
stepping : 1
cpu MHz : 2200.000
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 sep mtrr pge mca cmov pat pse36 clflush mmx f...

I have the Acer Aspire L5100.

Same problem here, only one core recognized.

I wouldn't mind running the 64bit version of Ubuntu, but unfortunately the Atheros AR5007EG WLAN NIC is not natively supported by Linux (madwifi). There is a new madwifi patch, but it only runs on 32bit.
That leaves me with ndiswrapper and windoze driver. I tried it, but the setup made the entire system unbearably unstable, not to mention the gargantua cpu ressource munching of the wrapper.

I decided to try the brand new Fedora i386 Live-CD which comes with kernel 2.6.25.
Booting the CD in (default) quiet mode gives the following error:
...
Booting the kernel.
tick-braodcast: ignoring broadcast for offline CPU #1
...

So still the same problem: 2nd core works with 64-bit kernel but not with any i386 kernel.

(Because onboard WLAN doesn't work with 64-bit I tried all my USB WLAN sticks.
 Three different chipsets, but none works with 64-bit (they do with 32-bit). Annoying ...)

Erik

i have the same problem here with ubuntu 8.04 x86 desktop edition.
only one core is viewed by the kernel as reported by /proc/cpuinfo or monitor application.

it works with a 2.6.24 kernel on ArchLinux http://www.archliunx.org !
so the big distro fail where the small ones do a better job.
may be it has something to do with the DSDT acpi table. i see that there is one in use in ubuntu here while none for archlinux.

i have a dell inspiron 531; athlon 64 x2 4400+, MCP61 chipset,

i have
CPU #1 not responding - cannot use it.

in dmesg during the booting process

Offering this as it may help diagnose this issue. I have it operating BOTH ways on two identical systems.

System #1. Dell Inspiron 531s, Factory setup, 1 GB RAM, Processor name string: AMD Athlon(tm) 64 X2 Dual Core Processor 4000+. It reports only 1 CPU responding, (using system monitor)

This system was originally built from an Ubuntu Desktop 7.10, i386.
I added the Myth Frontend using the "Add/Remove" gnome-app-install
I Upgraded to 8.04 using Update Manager. It apparently noticed the "myth" installation and upgraded like a mythbuntu installation. The system now starts up more like a mythbuntu system (mythbuntu logo splash), but I use it as a standard Ubuntu Desktop and only start the Myth Frontend as needed.

System #2 Same hardware as System #1. It reports 2 CPUs, (using system monitor)

This system was originally built from a "mythbuntu 7.10" installation and serves as a permanent mythTV backend.
I upgraded to 8.04 using Update Manager. Upgrade went as expected.

So I have two systems with identical hardware, running essentially the same kernel, that report different behaviors of the dual-core Athlon processor. I'm willing to try whatever you think might be helpful in diagnosing this issue.

Jim - Could you please add the full output of 'sudo dmidecode' for both systems as attachments to this bug report so we can try and troubleshoot this issue? Thanks in advance.

I'm attaching the output. Unfortunately, the systems no longer exhibit the behavior. Either something in the last several patches has fixed the issue, or I have inadvertently changed some configuration.

I've been accepting updates; however, I hadn't actually checked to see if the issue remained after each one, so I can't be sure exactly when it started working. Dangit! As a programmer, I'm usually more careful than that.

Sorry, I know how hard it is to track down machine dependent issues. If there is anything else I can collect, let me know.

Problem still exists with latest updates.

Here is the dmidecode output from the Acer L5100 PC
(identical output with i386 and x86_64 system)

Erik

Just to be absolutely clear which kernel version are you running Jim and Erik?

Both of my systems are currently running:
jim@jim-desktop:~$ uname -a
Linux jim-desktop 2.6.24-17-generic #1 SMP Thu May 1 14:31:33 UTC 2008 i686 GNU/Linux

Have just updated from 6.06 to 8.04. on an old dell insperation 410 dual PentiumII. Under 6.06 by default only one processor was enabled. By searching in Synaptic for linux-686-SMP you found the new kernel, installed and Bob's yer uncle, it all worked.
However, under 8.04 even though it claims to be an SMP aware kernel only one processor is working.

Is it worth waiting for an update or should I just downgrade back to 6.06 I have 3 children waiting to jump on this machine and give it hell (as they have done quite happily for years under 6.06)

same problem at MacBook

cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 15
model name : Intel(R) Core(TM)2 CPU T5600 @ 1.83GHz
stepping : 2
cpu MHz : 1833.000
cache size : 2048 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr lahf_lm
bogomips : 3661.66
clflush size : 64

Guys, were is my core? :)

Enable updates in your synaptic package manager so that you get the 2.6.24-19 kernel which has a fix for this issue.
System/Administration/Synaptic Package Manager/Settings/Repositories/Updates/Recommended Updates

Thanks for the hard work!
If we are talking about the latest 2.6.24-19.34 (generic) kernel (installed 2008-06-18), I am sorry to say that it makes no difference here.
Btw, I also tried latest kernel from kernel.org, tried compiling as K8, tried disabling ACPI in Grub. No luck.

Awwww, the bug isn't fixed: the kernel upgrade doesn't help!

I have the same problem on an AMD Phenom 9600 Quad-core processor running the latest kernel 2.6.24-19 on a board with ATI RS690 chipset. Only one of the four cores comes up. From all I see so far (google), it seems that the problem only exists for AMD dual/triple/quad core processors running on ATI RS690 or ATI790 chipsets. Did anyone incur the problem on a non-ATI chipset?

Linux sokrates 2.6.24-19-generic #1 SMP Wed Jun 18 14:43:41 UTC 2008 i686 GNU/Linux

Thanks everybody for all the work done already!

problem still exists with 32-bit version of the 2.6.24-19 kernel

It appears to be true that the bug only shows in AMD chipsets, i've tried myself with a brand new AMD 770 based motherboard and my old and faithfull M2N32-SLI which is nForce 590 and it does not shows on the nVidia chipset.

I also do not remember this happening with feisty but have not tried.

Using 8.04.1

Same problem here with an AMD Athlon(tm) X2 Dual Core Processor BE-2300, after trying numerous solutions and distributions I've given up on making the dual core work with 32 bit 2.6.24-X generic kernels.

2.6.25.10 - Still doesn't use both cores
2.6.26-RC9 - Both cores work

So it appears the growing number of AMD users with this problem will have to wait for Intrepid before being able to fully utilize our machines. As a band aid I am using 2.6.26-3-generic from the Intrepid alpha installed in 8.04.1, which works but leads to minor problems, such as not being able to compile ATI drivers, and corrupted boot splash display.

I confirm that both cores work with newest kernel 2.6.26.

I found the following instructions to "ubuntu" the kernel sources (as root):
You need the compiler stuff (aptitude install build-essential?) and make-kpkg:

Get linux-2.6.26.tar.bz2, e.g. from www.kernel.org
# tar xvfj linux-2.6.26.tar.bz2
# cd linux-2.6.26
# make-kpkg clean
# cp /boot/config<your_version> ./oldconfig
# make oldconfig
Press <return> a lot to confirm default answers ;-)
# make-kpkg --initrd --revision cpubug001 kernel_image
# cd ..
# dpkg -i ./linux-image-2.6.26*deb
(This will setup everything in /boot so you can boot the new kernel)

After rebooting both cpu cores are listed - yippee-ki-yay!

#cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 107
model name : AMD Athlon(tm) 64 X2 Dual Core Processor 4200+
stepping : 2
cpu MHz : 1000.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
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 sep 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 3dnowprefetch
bogomips : 2062.69
clflush size : 64
power management: ts fid vid ttp tm stc 100mhzsteps

processor : 1
...
core id : 1
...
apicid : 1
initial apicid : 1
...

The Ubuntu Kernel Team is planning to move to the 2.6.27 kernel for the upcoming Intrepid Ibex 8.10 release. As a result, the kernel team would appreciate it if you could please test this newer 2.6.27 Ubuntu kernel. There are one of two ways you should be able to test:

1) If you are comfortable installing packages on your own, the linux-image-2.6.27-* package is currently available for you to install and test.

--or--

2) The upcoming Alpha5 for Intrepid Ibex 8.10 will contain this newer 2.6.27 Ubuntu kernel. Alpha5 is set to be released Thursday Sept 4. Please watch http://www.ubuntu.com/testing for Alpha5 to be announced. You should then be able to test via a LiveCD.

Please let us know immediately if this newer 2.6.27 kernel resolves the bug reported here or if the issue remains. More importantly, please open a new bug report for each new bug/regression introduced by the 2.6.27 kernel and tag the bug report with 'linux-2.6.27'. Also, please specifically note if the issue does or does not appear in the 2.6.26 kernel. Thanks again, we really appreicate your help and feedback.

I already upgraded ("update-manager -d" to Intrepid a few days ago and meanwhile also have kernel 2.6.27 in use after latest "apt-get dist-upgrade".

I still have some issues with Intrepid (crashing "gnome backend" apps), but I can see both CPU cores are detected,
so this bug (213011) is fixed with either kernel 2.6.26 or 2.6.27.

Erik

(If any L5100 owners read this: The latest ATI-driver (8.8) doesn't compile properly with newer kernels (looks like smp_call_function has different argument list now). For the time being the only way to get acceptable graphics is
to use "radeonhd" driver, neither vesa nor radeon give good results (e.g. max resolution 800x600)).

Thanks for the update Erik. I'm going to mark this "Fix Released" for Intrepid.

I have an AMD Athlon64 X2 5600+ and I am only getting one CPU core working, as evidenced by /proc/cpuinfo:

processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 67
model name : AMD Athlon(tm) 64 X2 Dual Core Processor 5600+
stepping : 3
cpu MHz : 1000.000
cache size : 1024 KB
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow rep_good nopl pni cx16 lahf_lm cmp_legacy svm extapic cr8_legacy
bogomips : 2010.27
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: ts fid vid ttp tm stc

Per a decision made by the Ubuntu Kernel Team, bugs will longer be assigned to the ubuntu-kernel-team in Launchpad as part of the bug triage process. The ubuntu-kernel-team is being unassigned from this bug report. Refer to https://wiki.ubuntu.com/KernelTeamBugPolicies for more information. Thanks.