[Buildroot] [PATCH 1/2] qemu-system: new host package

[Arnout Vandecappelle <arnout@mind.be>]

On 04/12/13 13:48, Gustavo Zacarias wrote:
> On 12/04/2013 09:33 AM, Thomas Petazzoni wrote:
>
>> Yes, I agree, the user mode emulation should probably be removed. It
>> simply cannot work properly, because we have no way of guaranteeing
>> that the kernel headers used for the target toolchain are older than
>> the kernel running on the system.

  It's not possible to do it in Config.in, but it's easy to do during the 
build: compare /usr/include/linux/version.h with 
$(STAGING_DIR)/usr/include/linux/version.h

  Or am I missing something? I admit, it assumes that the distro installs 
kernel headers corresponding to the running kernel (but a distro that 
doesn't do that is pretty broken), and it assumes that you'll run qemu on 
the build machine.


>> And even if we want to keep the user mode emulation, I think there
>> should be one single package. Nothing prevents from having sub-options
>> to enable either the user mode or system mode emulation, or both, or to
>> have a version selection.
>
> A single package prevents different versions of -user and -system (at
> least in a nice way).

  We do it for gcc, binutils, ... and it doesn't look that ugly to me. 
It's mostly the Config.in part that looks ugly.


> Sometimes the latest version of qemu doesn't play nice with some kernel
> versions because of newer OpenBIOS/other BIOSes versions breaking with
> newer kernels - it's a common scenario for non-x86/x86_64.
> And there may be some particular need for -user to be a newer or
> different version than system, though i can't come up with any idea of why.
> At the moment i don't think -user is useful for anything in particular
> because of the limitations you wrote.
> Problem is building two different versions in a single package wouldn't
> be all that great, for all intents and purposes they would be two
> packages anyway.

  The two packages would be 90% identical (except for needless 
divergences, like one using generic-package and the other using 
autotools-package). So I don't agree they would be two packages. The host 
and the target build of e.g. python differ more than these two.

  Regards,
  Arnout


-- 
Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
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