Re: [BUG 2.6.29_rc8] BIOS Bug: CPU MTRRs don't cover all of memory, losing 0MB of RAM.
From: Ozan ÃaÄlayan
Date: Mon Mar 16 2009 - 16:19:29 EST
Yinghai Lu wrote:
> can you check tip/master?
>
> http://people.redhat.com/mingo/tip.git/readme.txt
>
> and post boot log.
I compiled tip/master with the same configuration. Here's the head of the dmesg:
(BTW, I'm not getting this backtrace with 2.6.25.20. I know its rather old but maybe
it will help)
---
Initializing cgroup subsys cpuset
Linux version 2.6.29-rc8-tip-tip (root@stinson) (gcc version 4.3.2 (Pardus Linux) ) #1 SMP Mon Mar 16 21:26:14 EET 2009
KERNEL supported cpus:
Intel GenuineIntel
AMD AuthenticAMD
NSC Geode by NSC
Cyrix CyrixInstead
Centaur CentaurHauls
Transmeta GenuineTMx86
Transmeta TransmetaCPU
UMC UMC UMC UMC
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 000000000009f400 (usable)
BIOS-e820: 000000000009f400 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 00000000cfd43000 (usable)
BIOS-e820: 00000000cfd43000 - 00000000cfd4c000 (ACPI data)
BIOS-e820: 00000000cfd4c000 - 00000000cfd4d000 (usable)
BIOS-e820: 00000000cfd4d000 - 00000000d0000000 (reserved)
BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)
BIOS-e820: 00000000fec00000 - 00000000fed00000 (reserved)
BIOS-e820: 00000000fee00000 - 00000000fee10000 (reserved)
BIOS-e820: 00000000ffc00000 - 0000000100000000 (reserved)
BIOS-e820: 0000000100000000 - 000000082ffff000 (usable)
DMI 2.5 present.
last_pfn = 0x82ffff max_arch_pfn = 0x1000000
MTRR default type: uncachable
MTRR fixed ranges enabled:
00000-9FFFF write-back
A0000-BFFFF uncachable
C0000-FFFFF write-protect
MTRR variable ranges enabled:
0 base 0000000000 mask 0000000000 write-back
1 base 00CFF00000 mask FFFFF00000 uncachable
2 base 00D0000000 mask FFF0000000 uncachable
3 base 00E0000000 mask FFE0000000 uncachable
4 base 0000004000 mask FFFFFFF000 uncachable
5 base 0000005000 mask FFFFFFF000 uncachable
6 base 0000006000 mask FFFFFFF000 uncachable
7 base 0000007000 mask FFFFFFF000 uncachable
x86 PAT enabled: cpu 0, old 0x7040600070406, new 0x7010600070106
get_mtrr: cpu0 reg00 base=0000000000 size=0010000000 write-back
get_mtrr: cpu0 reg01 base=00000cff00 size=0000000100 uncachable
get_mtrr: cpu0 reg02 base=00000d0000 size=0000010000 uncachable
get_mtrr: cpu0 reg03 base=00000e0000 size=0000020000 uncachable
get_mtrr: cpu0 reg04 base=0000000004 size=0000000001 uncachable
get_mtrr: cpu0 reg05 base=0000000005 size=0000000001 uncachable
get_mtrr: cpu0 reg06 base=0000000006 size=0000000001 uncachable
get_mtrr: cpu0 reg07 base=0000000007 size=0000000001 uncachable
e820 update range: 0000000000004000 - 0000000000008000 (usable) ==> (reserved)
e820 update range: 00000000cff00000 - 0000000100000000 (usable) ==> (reserved)
WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing 0MB of RAM.
------------[ cut here ]------------
WARNING: at arch/x86/kernel/cpu/mtrr/cleanup.c:1079 mtrr_trim_uncached_memory+0x2a9/0x2cd()
Hardware name: ProLiant DL580 G5
Modules linked in:
Pid: 0, comm: swapper Not tainted 2.6.29-rc8-tip-tip #1
Call Trace:
[<c0133871>] warn_slowpath+0x71/0xa8
[<c011e23a>] ? default_spin_lock_flags+0x9/0xb
[<c03aad3c>] ? _spin_unlock_irqrestore+0x17/0x1b
[<c011e23a>] ? default_spin_lock_flags+0x9/0xb
[<c03aad3c>] ? _spin_unlock_irqrestore+0x17/0x1b
[<c0133edd>] ? release_console_sem+0x176/0x1a3
[<c0134358>] ? vprintk+0x276/0x299
[<c03a87cc>] ? printk+0xf/0x13
[<c054aece>] mtrr_trim_uncached_memory+0x2a9/0x2cd
[<c0545cf5>] setup_arch+0x43c/0x9ab
[<c0133edd>] ? release_console_sem+0x176/0x1a3
[<c0134358>] ? vprintk+0x276/0x299
[<c0134358>] ? vprintk+0x276/0x299
[<c0548759>] ? __reserve_early+0xe4/0xf8
[<c03a87cc>] ? printk+0xf/0x13
[<c0543580>] start_kernel+0x77/0x323
[<c0543085>] __init_begin+0x85/0x8d
---[ end trace 4eaa2a86a8e2da22 ]---
update e820 for mtrr
--
Ozan ÃaÄlayan
<ozan_at_pardus.org.tr>
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