RE: Linux 2.6.38.4 : regression due to x86 AMD ARAT feature

From: Ostrovsky, Boris
Date: Sun Apr 24 2011 - 15:44:40 EST

Next message: favourndoye: "Hello my love, My name is Favour Ndoye,i come across and read through your profile today and i became interested in you,i will also like to know you the more,and i want you to send an e-mail to my e-mail address so i can give you my picture for you to know whom i am and for the both of us to know each other very well and better in life,and we can achieve it in future because ture love and feeling means alot in future.Here is my private e-mail address you can contact me with it.(favourndoye42@gmail.com)I am waiting for your mail to my e-mail address above and aslo, Remember the distance or colour does not matter but love,feeling,e-motions and sympathetic love matters alot in life. Thanks,and i promise to be honest and to keep a very good relationship with you. Favour. favourndoye42@gmail.com"
Previous message: Jean Delvare: "Re: [lm-sensors] [PATCH] thermal: Drop CONFIG_THERMAL_HWMON"
In reply to: JÃrg-Volker Peetz: "Re: Linux 2.6.38.4 : regression due to x86 AMD ARAT feature"
Next in thread: Jörg-Volker Peetz: "Re: Linux 2.6.38.4 : regression due to x86 AMD ARAT feature"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

It's an old family fh processor (CPUID 00020F42) that cpu_has_amd_erratum(amd_erratum_400) apparently hasn't picked up. Since all fh processors are affected by this erratum I'll replace "c->x86 >= 0xf" with "c->x86 > 0xf" (and probably fix erratum formula anyway).

-boris
________________________________________
From: Jörg-Volker Peetz [peetz@xxxxxxxxxxxxxxx]
Sent: Sunday, April 24, 2011 2:55 PM
To: Borislav Petkov; Jörg-Volker Peetz; linux-kernel@xxxxxxxxxxxxxxx; Ostrovsky, Boris; Herrmann3, Andreas; Petkov, Borislav
Subject: Re: Linux 2.6.38.4 : regression due to x86 AMD ARAT feature

Borislav Petkov wrote, on 04/24/11 20:20:
> On Sun, Apr 24, 2011 at 10:06:36AM +0200, Jörg-Volker Peetz wrote:
>> With 2.6.38.4 the clock slows down and the affected laptop sometimes, e.g. for
>> the output of "ps axuw" to appear, needs an input from the keyboard or the
>> touchpad. Please find attached the kernel config file and the output of dmesg.
>>
>> Commenting out the the lines
>>
>> if (c->x86 >= 0xf && !cpu_has_amd_erratum(amd_erratum_400))
>> set_cpu_cap(c, X86_FEATURE_ARAT);
>>
>> in arch/x86/kernel/cpu/amd.c makes this laptop work as before with kernel
>> 2.6.38.3. I think these lines came with commit
>> d7b7f0c401303dd7eafcff11752fe74d3b75c766.
>
> Hmm, interesting.
>
> Can you send also /proc/cpuinfo please?
>
> Looks like your CPU is a single core K8 revE or something but we'd need
> the exact family info.
>
> Thanks.
>

Here it comes:

processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 36
model name : AMD Turion(tm) 64 Mobile Technology MT-40
stepping : 2
cpu MHz : 800.000
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 syscall nx mmxext fxsr_opt lm 3dnowext 3dnow rep_good
nopl pni lahf_lm
bogomips : 1592.98
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

This is a nice mobile processor and i thought it was sold quite a lot.
--
Best regards,
Jörg-Volker.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/