RE: 256 apic id for amd64

From: YhLu (YhLu_at_tyan.com)
Date: 01/08/05

  • Next message: Dave Airlie: "Re: 2.6.10-mm2" 
    To: Mikael Pettersson <mikpe@csd.uu.se>, ak@muc.de
Date:	Fri, 7 Jan 2005 18:53:24 -0800

    I mean keep the bsp physical apic id using 0.

    YH

    -----Original Message-----
    From: Mikael Pettersson [mailto:mikpe@csd.uu.se]
    Sent: Friday, January 07, 2005 6:38 PM
    To: YhLu; ak@muc.de
    Cc: Matt_Domsch@dell.com; discuss@x86-64.org; jamesclv@us.ibm.com;
    linux-kernel@vger.kernel.org; suresh.b.siddha@intel.com
    Subject: Re: 256 apic id for amd64

    On Fri, 7 Jan 2005 22:12:00 +0100, Andi Kleen wrote:
    >On Fri, Jan 07, 2005 at 01:14:24PM -0800, YhLu wrote:
    >> After keep the bsp using 0, the jiffies works well. Werid?
    >
    >Probably a bug somewhere. But since BSP should be always
    >0 I'm not sure it is worth tracking down.

    I hope by "0" you're referring to a Linux kernel defined
    software value and _not_ what the HW or BIOS conjured up!

    Case in point: I was involved a while ago in tracking down
    and fixing a local APIC enumeration bug in the x86-32 (i386)
    kernel code, where the kernel failed miserably on some
    dual K7 boxes because (a) only one CPU socket was populated,
    (b) the BIOS assigned that CPU a non-zero ID, and (c) the
    kernel (apic.c) had a bug which triggered when BSP ID != 0.

    Never trust a BIOS to DTRT.

    /Mikael
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  • Next message: Dave Airlie: "Re: 2.6.10-mm2"

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