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

From: Paul E. McKenney
Date: Mon Jan 23 2023 - 14:12:50 EST


On Tue, Jan 24, 2023 at 02:01:50AM +0700, Ammar Faizi wrote:
> On Mon, Jan 23, 2023 at 09:40:03AM -0800, Paul E. McKenney wrote:
> > I looked for that, but didn't find it, so thank you!
> >
> > (Yes, I should have used dpkg, but I was lazy.)
> >
> > 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.
>
> This is an interesting bug.
>
> I'm a bit reluctant to say that this is a qemu bug. But I can't
> reproduce it on my machine. I use qemu that comes from Ubuntu 22.04.
>
> FWIW, my qemu version is:
>
> $ qemu-x86_64 -version
> qemu-x86_64 version 6.2.0 (Debian 1:6.2+dfsg-2ubuntu6.6)
> Copyright (c) 2003-2021 Fabrice Bellard and the QEMU Project developers
>
> I'll take a look at that gettimeofday() code and see if we have a bug in
> it. In meantime, could you send your qemu version info?

Thank you for looking into this, and here you go:

$ qemu-x86_64 -version
qemu-x86_64 version 4.2.1 (Debian 1:4.2-3ubuntu6.24)
Copyright (c) 2003-2019 Fabrice Bellard and the QEMU Project developers

The version that I built by hand (which passed all tests) is as follows:

$ /home/git/qemu/build/qemu-x86_64 -version
qemu-x86_64 version 7.2.0 (v7.2.0)
Copyright (c) 2003-2022 Fabrice Bellard and the QEMU Project developers

Thanx, Paul