Re: [Qemu-ppc] [Qemu-devel] ELF load command alignment not page-aligned

[Richard Henderson]

On 9/17/19 7:40 AM, Peter Maydell wrote:
> On Tue, 17 Sep 2019 at 11:49, Philippe Mathieu-Daudé <address@hidden> wrote:
>>
>> Cc'ing PPC folks and Laurent.
>>
>> On 9/16/19 11:06 PM, Niccolò Belli wrote:
>>> Hi,
>>> I'm trying to use qemu-user-static to chroot into a foreign amd64
>>> environment from my ppc64le host.
>>> The host has a 64k page size, while x86_64 uses 4k.
>>> I get those errors while loading shared libraries: "ELF load command
>>> alignment not page-aligned"
>>> Is there any way to fix this? I cannot simply switch to 4k page size
>>> because my btrfs filesystem won't mount anymore (it requires the
>>> sectorsize to be equal to the page size).
> 
> I vaguely recall that the answer is that we don't really
> support running a linux-user guest which has a smaller page
> size than the host. There are some sort-of-hacks in the code,
> so some simple cases might more-or-less work, but I'm not
> very surprised that you've run into something that doesn't
> work.
> 
> Cc:ing Richard who probably has a more accurate answer.

You are correct that this combination will not work.

This combination is exactly why I've proposed enabling softmmu for linux-user.
 With that, arbitrary mappings can be made between host and guest.  But it's a
fair amount of effort, which no one has yet found time for.


r~