Re: [Qemu-devel] Cryptic errors from PIP install if missing openssl-devel

[Cleber Rosa]

On Fri, Sep 06, 2019 at 11:43:58AM -0300, Eduardo Habkost wrote:
> On Fri, Sep 06, 2019 at 10:34:16AM +1000, David Gibson wrote:
> > On Thu, Sep 05, 2019 at 09:38:24AM -0400, Cleber Rosa wrote:
> > > On Thu, Sep 05, 2019 at 12:09:24PM +1000, David Gibson wrote:
> > > > On Wed, Sep 04, 2019 at 03:57:17PM -0400, Cleber Rosa wrote:
> > > > > 
> > > > > Hi David,
> > > > > 
> > > > > I've pushed a branch here (most of the commits have already been sent
> > > > > separately):
> > > > > 
> > > > >    https://github.com/clebergnu/qemu/tree/ppc64
> > > > > 
> > > > > I've tested on a RHEL 8 ppc64le Power 9, and it seems to work for me.
> > > > > My steps for building QEMU:
> > > > > 
> > > > >   - Configured with: '/home/cleber/src/qemu/configure' 
> > > > > '--enable-slirp=git' '--python=/usr/bin/python3' 
> > > > > '--target-list=x86_64-softmmu,ppc64-softmmu,arm-softmmu,aarch64-softmmu,mips-softmmu,mipsel-softmmu,mips64-softmmu,mips64el-softmmu,sh4-softmmu,s390x-softmmu,alpha-softmmu,m68k-softmmu,riscv64-softmmu'
> > > > >   - make
> > > > >   - make check-acceptance
> > > > > 
> > > > > Would you be able to test if that branch works smoothly for you?
> > > > 
> > > > So, with this tree I'm no longer getting problems if openssl-devel is
> > > > not installed, so that much looks good.
> > > > 
> > > > I am getting some different errors - I was seeing this before (with
> > > > openssl-devel installed) sometimes, but only sometimes.  I haven't yet
> > > > worked out a pattern for when they appeared.  They also don't appear
> > > > to be fatal, the rest of the tests seem to be running ok.  Any ideas?
> > > > 
> > > >  VENV    /home/dwg/qemu/build/rhel8/tests/venv
> > > >   PIP     /home/dwg/qemu/tests/requirements.txt
> > > >   AVOCADO tests/acceptance
> > > > Error running method "run" of plugin "html": 'Namespace' object has no 
> > > > attribute 'get'
> > > > Error running method "run" of plugin "varianter_cit": 'Namespace' 
> > > > object has no attribute 'get'
> > > 
> > > Hi David,
> > > 
> > > Yes, those should not be fatal.  Anyway, they are caused by two things:
> > > 
> > >  1) A second set of Avocado plugins installation with different versions
> > >     than the Avocado installation on QEMU's tests venv
> > 
> > Ah!  That'll be from the Avocado setup that Lukaš set up on there for
> > some different tests.
> > 
> > >  2) The tests' venv, which is created with "--system-site-packages",
> > >     option that is described as "Give the virtual environment access
> > >     to the system site-packages dir."
> > > 
> > > The motivation to have "--system-site-packages" is that, if the user
> > > had any of the "requirements.txt" depedencies installed system wide,
> > > the venv would simply use it and skip downloads.  Maybe we should make
> > > that an optional feature, disabled by default, so that the test's venv
> > > is better isolated and more predictable by default.
> > 
> > If pip doesn't have good enough version tracking that it's verifying
> > the correct versions of the installed packages as well as the
> > presence, then yes I tend to agree that keeping it better isolated
> > would be preferable.
> 
> pip ensures the right version of packages we request are
> installed, but Avocado plugins are separate packages and we don't
> tell pip anything about the plugins we are not using (but could be
> already installed in the system).

Right.

> 
> Cleber, does Avocado have any kind of plugin API versioning, so
> it could detect incompatible plugins before using them?
>

It does not.  And while making an exact version match requirement
between plugins and core Avocado would be easy, it would put unfair
(IMO) requirements on plugin writers.  It's quite possible that
an external plugin would work for many different avocado versions,
and the author wouldn't feel like updating it just to satisfy the
version check.

I'm not quite sure we should be trying to solve this problem here, but
I'm open to suggestions.

- Cleber.

> -- 
> Eduardo