Re: [PATCH 4/4] qemu: add bash and python to qemu's RDEPENDS

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Fri, 2013-11-22 at 09:32 +0100, Olof Johansson wrote:
> On 13-11-22 07:25 +0100, Hongxu Jia wrote:
> > Hi Saul,
> > 
> > The script could not be de-bashed,  it was made by create_wrapper
> > which is bashism:
> > Vim image/usr/bin/qemu-mips
> > ...
> > #! /bin/bash
> > realpath=`readlink -fn $0`
> > export QEMU_RESERVED_VA=0x0
> > exec -a `dirname $realpath`/qemu-mips `dirname $realpath`/qemu-mips.real "$@"
> > ...
> > 
> > The exec's -a option is bashism, so we need to add bash to RDEPENDS.
> 
> 1) Is the wrapper still necessary?
> 
> The comment above the do_install_append in the recipe:
> 
> # The following fragment will create a wrapper for qemu-mips user emulation
> # binary in order to work around a segmentation fault issue. Basically, by
> # default, the reserved virtual address space for 32-on-64 bit is set to 4GB.
> # This will trigger a MMU access fault in the virtual CPU. With this change,
> # the qemu-mips works fine.
> # IMPORTANT: This piece needs to be removed once the root cause is fixed!

Someone could retest it but as far as I know the issue still exists.

> 2) More generally, is -a generally necessary when exec'ing like this? Can't
>    this be solved in another way?

We've gone around in circles on this and yes, execing using -a is needed
and if we don't do that we hit other bugs. See the history of the
create_wrapper function.

Cheers,

Richard