TARGET_PAGE_BITS

TARGET_PAGE_BITS

[@ 2008-09-11 15:31 UTC (permalink / raw)]

Hi,

I'm trying to use KVM (74) on an ia64 server with the kernel 2.6.26 as 
recommanded. Everything is ok about compilation, installation.
But, when i'm trying to boot a guest, i got this error : Error! Host 
page size != qemu target page size, you may need to change 
TARGET_PAGE_BITS in qemu!host page size:0x4000.
I looked for how to change this value, i find qemu/target-ia64/cpu.h but 
i imagine that isn't the right place.
Any idea ?

Thanks for your help (and i would like to apologize for my rude english).
Sebastien

Re: TARGET_PAGE_BITS

[Alex Williamson]

On Thu, 2008-09-11 at 17:31 +0200, Sébastien Bassompierre wrote:
> Hi,
> 
> I'm trying to use KVM (74) on an ia64 server with the kernel 2.6.26 as 
> recommanded. Everything is ok about compilation, installation.
> But, when i'm trying to boot a guest, i got this error : Error! Host 
> page size != qemu target page size, you may need to change 
> TARGET_PAGE_BITS in qemu!host page size:0x4000.
> I looked for how to change this value, i find qemu/target-ia64/cpu.h but 
> i imagine that isn't the right place.
> Any idea ?

That's where I changed it in my local build tree and it works.  The
default appears to be set to match upstream Linux/ia64 defconfig, which
uses 64k pages.  I don't know why we don't detect this automatically at
build time.

Alex

-- 
Alex Williamson                             HP Open Source & Linux Org.

Re: TARGET_PAGE_BITS

[Jes Sorensen]

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>>>>> "Alex" = Alex Williamson <alex.williamson@hp.com> writes:

Alex> On Thu, 2008-09-11 at 17:31 +0200, Sébastien Bassompierre
Alex> wrote:
>> I'm trying to use KVM (74) on an ia64 server with the kernel 2.6.26
>> as recommanded. Everything is ok about compilation, installation.
>> But, when i'm trying to boot a guest, i got this error : Error!
>> Host page size != qemu target page size, you may need to change
>> TARGET_PAGE_BITS in qemu!host page size:0x4000.  I looked for how
>> to change this value, i find qemu/target-ia64/cpu.h but i imagine
>> that isn't the right place.  Any idea ?

Alex> That's where I changed it in my local build tree and it works.
Alex> The default appears to be set to match upstream Linux/ia64
Alex> defconfig, which uses 64k pages.  I don't know why we don't
Alex> detect this automatically at build time.

Actually doing a build time setting of host page size in qemu is
broken, it should be reworked to call getpagesize() but thats probably
going to be a bit more work :-(

Cheers,
Jes