2009-09-29 14:00:27

by Bo Branten

[permalink] [raw]
Subject: still mtrr problems


Hello,

when installing 8G RAM on an Intel DG965OT motherboard Linux will hang at
boot (or parhaps only become very very slow) if I dont add the boot option
mem=8192M, Windows Vista 64-bit works without any probelm on the same
hardware.

/proc/mtrr:
reg00: base=0x00000000 ( 0MB), size=2048MB: write-back, count=1
reg01: base=0x80000000 (2048MB), size=1024MB: write-back, count=1
reg02: base=0xc0000000 (3072MB), size= 256MB: write-back, count=1
reg03: base=0xcf800000 (3320MB), size= 8MB: uncachable, count=1
reg04: base=0xcf700000 (3319MB), size= 1MB: uncachable, count=1
reg05: base=0x100000000 (4096MB), size=4096MB: write-back, count=1
reg06: base=0x200000000 (8192MB), size= 512MB: write-back, count=1
reg07: base=0xd0000000 (3328MB), size= 256MB: write-combining, count=1

dmesg|grep e820:
[ 0.000000] BIOS-e820: 0000000000000000 - 000000000008f000 (usable)
[ 0.000000] BIOS-e820: 000000000008f000 - 00000000000a0000 (reserved)
[ 0.000000] BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
[ 0.000000] BIOS-e820: 0000000000100000 - 00000000cf561000 (usable)
[ 0.000000] BIOS-e820: 00000000cf561000 - 00000000cf56e000 (reserved)
[ 0.000000] BIOS-e820: 00000000cf56e000 - 00000000cf637000 (usable)
[ 0.000000] BIOS-e820: 00000000cf637000 - 00000000cf6e9000 (ACPI NVS)
[ 0.000000] BIOS-e820: 00000000cf6e9000 - 00000000cf6ed000 (usable)
[ 0.000000] BIOS-e820: 00000000cf6ed000 - 00000000cf6f2000 (ACPI data)
[ 0.000000] BIOS-e820: 00000000cf6f2000 - 00000000cf6f3000 (usable)
[ 0.000000] BIOS-e820: 00000000cf6f3000 - 00000000cf6ff000 (ACPI data)
[ 0.000000] BIOS-e820: 00000000cf6ff000 - 00000000cf700000 (usable)
[ 0.000000] BIOS-e820: 00000000cf700000 - 00000000d0000000 (reserved)
[ 0.000000] BIOS-e820: 00000000fff00000 - 0000000100000000 (reserved)
[ 0.000000] BIOS-e820: 0000000100000000 - 000000022c000000 (usable)


2009-09-29 19:28:50

by Yinghai Lu

[permalink] [raw]
Subject: Re: still mtrr problems

On Tue, Sep 29, 2009 at 6:52 AM, Bo Brant?n <[email protected]> wrote:
>
> Hello,
>
> when installing 8G RAM on an Intel DG965OT motherboard Linux will hang at
> boot (or parhaps only become very very slow) if I dont add the boot option
> mem=8192M, Windows Vista 64-bit works without any probelm on the same
> hardware.
>
> /proc/mtrr:
> reg00: base=0x00000000 ( ? 0MB), size=2048MB: write-back, count=1
> reg01: base=0x80000000 (2048MB), size=1024MB: write-back, count=1
> reg02: base=0xc0000000 (3072MB), size= 256MB: write-back, count=1
> reg03: base=0xcf800000 (3320MB), size= ? 8MB: uncachable, count=1
> reg04: base=0xcf700000 (3319MB), size= ? 1MB: uncachable, count=1
> reg05: base=0x100000000 (4096MB), size=4096MB: write-back, count=1
> reg06: base=0x200000000 (8192MB), size= 512MB: write-back, count=1
> reg07: base=0xd0000000 (3328MB), size= 256MB: write-combining, count=1
>
> dmesg|grep e820:
> [ ? ?0.000000] ?BIOS-e820: 0000000000000000 - 000000000008f000 (usable)
> [ ? ?0.000000] ?BIOS-e820: 000000000008f000 - 00000000000a0000 (reserved)
> [ ? ?0.000000] ?BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
> [ ? ?0.000000] ?BIOS-e820: 0000000000100000 - 00000000cf561000 (usable)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf561000 - 00000000cf56e000 (reserved)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf56e000 - 00000000cf637000 (usable)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf637000 - 00000000cf6e9000 (ACPI NVS)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf6e9000 - 00000000cf6ed000 (usable)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf6ed000 - 00000000cf6f2000 (ACPI data)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf6f2000 - 00000000cf6f3000 (usable)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf6f3000 - 00000000cf6ff000 (ACPI data)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf6ff000 - 00000000cf700000 (usable)
> [ ? ?0.000000] ?BIOS-e820: 00000000cf700000 - 00000000d0000000 (reserved)
> [ ? ?0.000000] ?BIOS-e820: 00000000fff00000 - 0000000100000000 (reserved)
> [ ? ?0.000000] ?BIOS-e820: 0000000100000000 - 000000022c000000 (usable)
> --

kernel should trim your e820 to 220000000, could be some strange MTRR
layout that we don't want to touch.

can you post whole bootlog with debug?

YH