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Subject: Re: [PATCH] arch/s390/configs: Change CONFIG_VIRTIO_CONSOLE to "m"
To:     Thomas Huth <thuth@redhat.com>, linux-s390@vger.kernel.org,
        Heiko Carstens <hca@linux.ibm.com>
Cc:     linux-kernel@vger.kernel.org, Vasily Gorbik <gor@linux.ibm.com>,
        Marc Hartmayer <mhartmay@linux.ibm.com>,
        Halil Pasic <pasic@linux.ibm.com>, cohuck@redhat.com
References: <20210428082442.321327-1-thuth@redhat.com>
 <c015ef3f-ff88-113b-a089-e2af9202399a@de.ibm.com>
 <6e44cc81-fe19-f75b-972f-5c4707f2410f@redhat.com>
From:   Christian Borntraeger <borntraeger@de.ibm.com>
Message-ID: <b75f0447-55d4-09b8-8f3e-d0d54471cac1@de.ibm.com>
Date:   Wed, 28 Apr 2021 23:03:22 +0200
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On 28.04.21 11:30, Thomas Huth wrote:
> On 28/04/2021 10.31, Christian Borntraeger wrote:
>> On 28.04.21 10:24, Thomas Huth wrote:
>>> In former times, the virtio-console code had to be compiled into
>>> the kernel since the old guest virtio transport had some hard de-
>>> pendencies. But since the old virtio transport has been removed in
>>> commit 7fb2b2d51244 ("s390/virtio: remove the old KVM virtio transport"),
>>> we do not have this limitation anymore.
>>> Commit bb533ec8bacd ("s390/config: do not select VIRTIO_CONSOLE via
>>> Kconfig") then also lifted the hard setting in the Kconfig system, so
>>> we can finally switch the CONFIG_VIRTIO_CONSOLE knob to compile this
>>> driver as a module now, making it more flexible for the user to only
>>> load it if it is really required.
>>
>> Isnt that a distro specific decision? I would be perfectly fine to have
>> this change in Fedora, Redhat and co.
> 
> Sure, I'll try to get it changed there, too.
> 
>> Not so sure about defconfig.
>> We often use the defconfig in our CI and development things to have a
>> kernel config that boots up fine, even without a ramdisk. I agree that
>> virtio console is no longer really the most important console but does
>> it really hurt?
> 
> Well, it's about a default configuration that should be fine for most users. I don't think that anybody really uses virtio-console in a ramdisk already ... or are you really doing that in your CI? If so, then please disregard my patch.

I think anybody uses the sclp console nowadays. The only question is, do
we care about manual configs with virtio-console?