Re: BIOS bug, APIC version if 0 for CPU#0

[Justin Mattock]

On Tue, Apr 22, 2008 at 1:49 PM, Kasper Sandberg <lkml@xxxxxxxxxxx> wrote:
> On Tue, 2008-04-22 at 06:10 +0000, Justin Mattock wrote:
>  > On Tue, Apr 22, 2008 at 5:21 AM, Jacek Luczak <difrost.kernel@xxxxxxxxx> wrote:
>  > > Hi,
>  > >
>  > >
>  > >  > Hello;
>  > >  > with the latest git on a macbook the system can barely boot without
>  > >  > freezing, a work around for me at leat is either disable smp, or once
>  > >  > booted  turn on glxgears,or compiling the kernel i.g. when using the
>  > >  > processors I'm not receiving a freeze, only when everything starts
>  > >  > lowering down. in dmesg I'm noticing BIOS bug, APIC version is 0 for
>  > >  > CPU#0! fixing up to 0x10. (tell you're hw vendor) could this be the
>  > >  > reason for the system freezes?,
>  > >
>  > >  I don't think so. On my machine there's no freezes with latest git and:
>  > >  ACPI: LAPIC (acpi_id[0x00] lapic_id[0x00] enabled)
>  > >  BIOS bug, APIC version is 0 for CPU#0! fixing up to 0x10. (tell your hw vendor)
>  > >  ACPI: LAPIC (acpi_id[0x01] lapic_id[0x01] enabled)
>  > >  BIOS bug, APIC version is 0 for CPU#0! fixing up to 0x10. (tell your hw vendor)
>  > >
>  > >  I've got exactly the same messages.
>  >
>  > Are you using a macbook aswell?
>  >
>  > >
>  > >
>  > >  > also I didnt have a camera handy on me
>  > >  > but the screen spit out = Bug spinlock lockup on CPU#0
>  > >  > swapper/0. c17fa7c0 PID 0, comm: swapper not tainted.
>  > >
>  > >  Can you try to write down more of those bug messages?
>  >
>  > Yeah,
>  >
>  > >
>  > >
>  > >  > I dont have a problem disabling smp, except when I cat /proc/cpuinfo I
>  > >  > don't see anything about my cores.
>  > >
>  > >  What exactly you expect to see in /proc/cpuinfp while smp is disabled?
>  >
>  > under smp I see cpu cores. disabling smp I dont see cpu cores, under
>  > cat /proc/cpuinfo.
>
>  well.. SMP is kindof support for multiple processors, be it in one
>  socket, or multiple sockets.. without SMP you will only be able to use 1
>  of your X cores.

Yeah disabling smp is not a good idea on a macbook pro, performace is horrible.

>  >
>  >
>  > >
>  > >
>  > >  > I know this is a stupid question
>  > >  > but will it hurt the system if smp is disabled
>  > >  > for the macbook pro ati chipset.?
>  > >
>  > >  No it won't.
>  > >
>  > >  -Jacek
>  > >
>  >
>  > Cool as long as the system Is o.k. disabling smp.
>  It is.. but with the limitations outlined above.
>  >   What about x86: PAT
>  > support is disabled. how do I enable this option?
>  > regards;
>  >
>
>
Thanks for the feedback, well I guess this would be either a
regression or a bug. I think the best would be to have somebody else
with a macbook pro 15' ati chipset confirm this freezeing as well,
before going out and jumping the gun, and filing a bug report.
regards;


-- 
Justin P. Mattock
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