Re: [PATCH 0/2] selftests/nolibc: small simplification of test development phase

From: Paul E. McKenney
Date: Mon Jan 23 2023 - 14:25:49 EST


On Mon, Jan 23, 2023 at 08:12:50PM +0100, Willy Tarreau wrote:
> On Mon, Jan 23, 2023 at 09:40:03AM -0800, Paul E. McKenney wrote:
> > Except that when I install Ubuntu 20.04's version, I get this:
> >
> > ------------------------------------------------------------------------
> >
> > $ sudo make run-user
> > MKDIR sysroot/x86/include
> > make[1]: Entering directory '/home/git/linux-rcu/tools/include/nolibc'
> > make[2]: Entering directory '/home/git/linux-rcu'
> > make[2]: Leaving directory '/home/git/linux-rcu'
> > make[2]: Entering directory '/home/git/linux-rcu'
> > INSTALL /home/git/linux-rcu/tools/testing/selftests/nolibc/sysroot/sysroot/include
> > make[2]: Leaving directory '/home/git/linux-rcu'
> > make[1]: Leaving directory '/home/git/linux-rcu/tools/include/nolibc'
> > CC nolibc-test
> > 32 gettimeofday_null = -1 EFAULT [FAIL]
> > See all results in /home/git/linux-rcu/tools/testing/selftests/nolibc/run.out
> >
> > ------------------------------------------------------------------------
> >
> > I have attached run.out.
> >
> > In contrast, with my hand-built qemu-x86_64, all tests passed.
> >
> > This might be just a version-related bug, but figured I should let you
> > guys know.
>
> Interesting. Maybe something differs in the way it passes expectedly
> invalid pointers to some syscalls. Keep in mind that it's using your
> local kernel also, that could make a difference. I'm not that much keen
> on trying to investigate that one to be honest, given that this user
> mode is really meant to ease the life of test developers like Ammar
> and myself who just want to focus on the correctness of the test they're
> adding and not that much on the validity of the test itself in this
> context. I suggest we keep this one in mind without putting too much
> effort on it for now.

Indeed, it is easy for me to remove qemu-user and re-install my
hand-built version. In fact, I just now did this and verified that
everything now passes. ;-)

Thanx, Paul