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References: <20220513181032.24484-1-dlatypov@google.com>
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From:   Brendan Higgins <brendanhiggins@google.com>
Date:   Wed, 6 Jul 2022 15:58:45 -0400
Message-ID: <CAFd5g47g6Tb4nMB-NQQAF3vXZ9FZj9YwcdP=E_-=5A6fBTbfNw@mail.gmail.com>
Subject: Re: [PATCH v2] kunit: tool: cosmetic: don't specify duplicate kernel
 cmdline options
To:     Daniel Latypov <dlatypov@google.com>
Cc:     davidgow@google.com, linux-kernel@vger.kernel.org,
        kunit-dev@googlegroups.com, linux-kselftest@vger.kernel.org,
        skhan@linuxfoundation.org
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On Fri, May 13, 2022 at 2:10 PM Daniel Latypov <dlatypov@google.com> wrote:
>
> Context:
> When using a non-UML arch, kunit.py will boot the test kernel with
> options like these by default (this is x86_64):
> > mem=1G console=tty kunit_shutdown=halt console=ttyS0 kunit_shutdown=reboot
>
> The first three options are added unconditionally but are only intended
> for UML.
>
> 1. 'mem=1G' is redundant with the '-m 1024' that we hard-code into the
>    qemu commandline.
>
> 2. We specify a 'console' for all tools/testing/kunit/qemu_configs/*.py
>    already, so 'console=tty' gets overwritten.
>
> 3. For QEMU, we need to use 'reboot', and for UML we need to use 'halt'.
>    If you switch them, kunit.py will hang until the --timeout expires.
>
> This patch:
> Having these duplicate options is a bit noisy.
> Switch so we only add UML-specific options for UML.
>
> I.e. we now get
> UML: 'mem=1G console=tty kunit_shutdown=halt' (unchanged)
> x86_64: 'console=ttyS0 kunit_shutdown=reboot'
>
> Side effect: you can't overwrite these options on UML w/ --kernel_arg.
> But you already couldn't for QEMU (console, kunit_shutdown), and why
> would you want to?
>
> Signed-off-by: Daniel Latypov <dlatypov@google.com>
> Reviewed-by: David Gow <davidgow@google.com>

Reviewed-by: Brendan Higgins <brendanhiggins@google.com>