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From:   Marco Elver <elver@google.com>
Date:   Thu, 14 Jul 2022 23:40:53 +0200
Message-ID: <CANpmjNP-YYB05skVuJkk9CRB=KVvS+5Yd+yTAzXC7MAkKAe4jw@mail.gmail.com>
Subject: Re: [PATCH 2/2] kcsan: test: Add a .kunitconfig to run KCSAN tests
To:     Daniel Latypov <dlatypov@google.com>
Cc:     David Gow <davidgow@google.com>,
        Brendan Higgins <brendanhiggins@google.com>,
        Shuah Khan <skhan@linuxfoundation.org>,
        Dmitry Vyukov <dvyukov@google.com>,
        KUnit Development <kunit-dev@googlegroups.com>,
        kasan-dev <kasan-dev@googlegroups.com>,
        "open list:KERNEL SELFTEST FRAMEWORK" 
        <linux-kselftest@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, 14 Jul 2022 at 22:23, Daniel Latypov <dlatypov@google.com> wrote:
>
> On Thu, May 19, 2022 at 6:24 AM Marco Elver <elver@google.com> wrote:
> > I'd keep it simple for now, and remove both lines i.e. make non-strict
> > the default. It's easy to just run with --kconfig_add
> > CONFIG_KCSAN_STRICT=y, along with other variations. I know that
> > rcutoruture uses KCSAN_STRICT=y by default, so it's already getting
> > coverage there. ;-)
>
> David decided to drop the parent patch (the new QEMU config) now
> --qemu_args was merged into the kunit tree.
> Did we want a standalone v2 of this patch?
>
> Based on Marco's comments, we'd change:
> * drop CONFIG_KCSAN_STRICT=y per this comment [1]
> * drop CONFIG_KCSAN_WEAK_MEMORY per previous comments
> Then for --qemu_args changes:
> * add CONFIG_SMP=y explicitly to this file
> * update the comment to show to include --qemu_args="-smp 8"
>
> Does this sound right?

Yes, sounds good to me, and thanks for remembering this. I'd prefer a
close-to-default config.

> [1] Note: there's also patches in kunit now so you could do
> --kconfig_add=CONFIG_KCSAN_STRICT=n to explicitly disable it. This
> wasn't possible before. Does that change what we want for the default?

I'd just have KCSAN_STRICT=n by default, and if desired it can be
added per kconfig_add just the same way.

Thanks,
-- Marco