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Subject: Re: [RFC PATCH v2 1/3] printk: Add function to set console to
 preferred console's driver
To:     Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>, Petr Mladek <pmladek@suse.com>,
        linux-serial@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Arvind Sankar <nivedita@alum.mit.edu>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        "David S. Miller" <davem@davemloft.net>,
        Feng Tang <feng.tang@intel.com>
References: <20200430161438.17640-1-alpernebiyasak@gmail.com>
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From:   Alper Nebi Yasak <alpernebiyasak@gmail.com>
Message-ID: <b1b5514e-936e-a5e4-3dd6-3e640a819ffc@gmail.com>
Date:   Fri, 1 May 2020 14:48:36 +0300
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On 01/05/2020 04:44, Sergey Senozhatsky wrote:
> Hmm. Preferred console selection is very fragile, there are too many
> setups and workarounds that even minor tweaks introduce regressions
> oftentimes.

All this would only execute on #ifdef VT_CONSOLE right now and I think
they can be gated further by a new Kconfig like VT_CONSOLE_PREFERRED, if
that'd make it better.

> We have, by the way, a pending patchset which changes the same
> are - preferred console selection.
>
> git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk.git for-5.7-preferred-console

I was working on next-20200430 where that patchset is already included,
can confirm it doesn't solve this problem. I hope I've correctly avoided
breaking it by setting its "has_preferred_console" variable (thus this
patchset somewhat depends on that).

> Let me take a look over the weekend.

Thanks in advance.