Messages in this thread | | | Date | Fri, 25 Jan 2008 00:39:25 -0800 | From | "Yinghai Lu" <> | Subject | Re: [PATCH] x86: trim ram need to check if mtrr is there v2 |
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On Jan 25, 2008 12:13 AM, Yinghai Lu <yhlu.kernel@gmail.com> wrote: > > On Jan 24, 2008 11:43 PM, Jeremy Fitzhardinge <jeremy@goop.org> wrote: > > > > Yinghai Lu wrote: > > > [PATCH] x86: trim ram need to check if mtrr is there v2 > > > > > > > > >>> Jeremy Fitzhardinge wrote: > > >>> When booting a current x86.git kernel under kvm, I get this: > > >>> > > >>> (qemu) Linux version 2.6.24-rc8 (jeremy@ezr) (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 > > >>> *************** > > >>> > > >> H. Peter Anvin wrote: > > >> Looks like the code doesn't check that the CPU *has* MTRRs... > > >> > > > > > > so check it mtrr is there, also check if mem less 4G and is AMD as early > > > > > > > Thanks, this gets me to usermode under kvm. > > i think the is 0xffffffff to 0xffffffffUL make the difference. > > the cpu mode in KVM/qemu may cpu_has_mtrr, but doesn't really have > return mtrr msr with correct value. > > is_cpu(INTEL) already make sure we have mtrr_if got assigned and cpu_has_mtrr. > > may need to fix qemu instead... > > Can you try post /proc/mtrr for your guest in kvm/qemu?
jeremy,
can you try v3 patch?
Thanks
YH
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