Host with i686 kernel

Host with i686 kernel

[Alexander Smirnov]

Hi all,

I've faced with the problem building Isar on i686 host kernel. The amd64 
configuration fails on debootstrap with error:

  - mount: cannot execute binary file: Exec format error

As I found, this error happened when debootstrap tries to run 
'/bin/mount' in chroot. The issue is that there is no binfmt for x86_64.

I've found a binfmt config for AMD64:

http://seeblog.seenet.ca/2016/03/running-amd64-binaries-on-an-i386-linux-system/

But it works very unstable (possibly this is the reason why it's not 
included in default package).

Conclusion: Isar can't build 64-bit systems on 32-bit host kernels.

Alex

Re: Host with i686 kernel

[Henning Schild]

Am Tue, 1 May 2018 21:19:19 +0300
schrieb Alexander Smirnov <asmirnov@ilbers.de>:

> Hi all,
> 
> I've faced with the problem building Isar on i686 host kernel. The
> amd64 configuration fails on debootstrap with error:
> 
>   - mount: cannot execute binary file: Exec format error
> 
> As I found, this error happened when debootstrap tries to run 
> '/bin/mount' in chroot. The issue is that there is no binfmt for
> x86_64.
> 
> I've found a binfmt config for AMD64:
> 
> http://seeblog.seenet.ca/2016/03/running-amd64-binaries-on-an-i386-linux-system/
> 
> But it works very unstable (possibly this is the reason why it's not 
> included in default package).
> 
> Conclusion: Isar can't build 64-bit systems on 32-bit host kernels.

I think that is OK, 32bit x86 is dead. To follow up one could open a
debian bug about the missing/broken binfmt and document that limitation
in Isar.

Henning

> Alex
> 

Re: Host with i686 kernel

[Jan Kiszka]

On 2018-05-02 10:52, [ext] Henning Schild wrote:
> Am Tue, 1 May 2018 21:19:19 +0300
> schrieb Alexander Smirnov <asmirnov@ilbers.de>:
> 
>> Hi all,
>>
>> I've faced with the problem building Isar on i686 host kernel. The
>> amd64 configuration fails on debootstrap with error:
>>
>>   - mount: cannot execute binary file: Exec format error
>>
>> As I found, this error happened when debootstrap tries to run 
>> '/bin/mount' in chroot. The issue is that there is no binfmt for
>> x86_64.
>>
>> I've found a binfmt config for AMD64:
>>
>> http://seeblog.seenet.ca/2016/03/running-amd64-binaries-on-an-i386-linux-system/
>>
>> But it works very unstable (possibly this is the reason why it's not 
>> included in default package).
>>
>> Conclusion: Isar can't build 64-bit systems on 32-bit host kernels.
> 
> I think that is OK, 32bit x86 is dead. To follow up one could open a
> debian bug about the missing/broken binfmt and document that limitation
> in Isar.

It could easily be a qemu-user issue as well. QEMU always had problems
mapping the full register set of x86-64 on the constrained one of i386.
Plus, no one is using 32-bit anymore (except some crazy embedded and/or
nostalgic folks).

Jan

-- 
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux