On Thursday 24 January 2008 05:49:00 pm H. Peter Anvin wrote:
> Jeremy Fitzhardinge wrote:
> > When booting a current x86.git kernel under kvm, I get this:
> >
> > (qemu) Linux version 2.6.24-rc8 ([EMAIL PROTECTED]) (gcc version 4.1.2
> > 20070925
> > (Red Hat 4.1.2-33)) #1928 SMP PREEMPT Thu Jan 24 17:09:04 PST 2008
> > early_ioremap_init()
> > BIOS-provided physical RAM map:
> > BIOS-e820: 0000000000000000 - 000000000009fc00 (usable)
> > BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)
> > BIOS-e820: 00000000000e8000 - 0000000000100000 (reserved)
> > BIOS-e820: 0000000000100000 - 000000001fff0000 (usable)
> > BIOS-e820: 000000001fff0000 - 0000000020000000 (ACPI data)
> > BIOS-e820: 00000000fffc0000 - 0000000100000000 (reserved)
> > console [earlyser0] enabled
> > 0MB HIGHMEM available.
> > 511MB LOWMEM available.
> > Scan SMP from c0000000 for 1024 bytes.
> > Scan SMP from c009fc00 for 1024 bytes.
> > Scan SMP from c00f0000 for 65536 bytes.
> > Scan SMP from c009fc00 for 1024 bytes.
> > ***************
> > **** WARNING: likely BIOS bug
> > **** MTRRs don't cover all of memory, trimmed 131056 pages
> > ***************
>
> Looks like the code doesn't check that the CPU *has* MTRRs...
please try this
[PATCH] x86: trim RAM need to check if mtrr is there
Signed-off-by: Yinghai Lu <[EMAIL PROTECTED]>
diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
index a1551d0..a0b6f55 100644
--- a/arch/x86/kernel/cpu/mtrr/main.c
+++ b/arch/x86/kernel/cpu/mtrr/main.c
@@ -646,9 +646,6 @@ static __init int amd_special_default_mtrr(unsigned long
end_pfn)
{
u32 l, h;
- /* Doesn't apply to memory < 4GB */
- if (end_pfn <= (0xffffffff >> PAGE_SHIFT))
- return 0;
if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
return 0;
if (boot_cpu_data.x86 < 0xf || boot_cpu_data.x86 > 0x11)
@@ -682,6 +679,12 @@ int __init mtrr_trim_uncached_memory(unsigned long end_pfn)
mtrr_type type;
u64 trim_start, trim_size;
+ /* Doesn't apply to memory < 4GB */
+ if (end_pfn <= (0xffffffffUL >> PAGE_SHIFT))
+ return 0;
+
+ if (!cpu_has_mtrr)
+ return 0;
/*
* Make sure we only trim uncachable memory on machines that
* support the Intel MTRR architecture:
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
