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From: Michael Ellerman <mpe@ellerman.id.au>
To: Nicholas Piggin <npiggin@gmail.com>, linuxppc-dev@lists.ozlabs.org
Cc: Jiri Slaby <jslaby@suse.com>, linux-kernel@vger.kernel.org, Nicholas Piggin <npiggin@gmail.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH 04/15] powerpc/powernv: opal-kmsg use flush fallback from console code
In-Reply-To: <20180430145558.4308-5-npiggin@gmail.com>
References: <20180430145558.4308-1-npiggin@gmail.com> <20180430145558.4308-5-npiggin@gmail.com>
Date: Fri, 04 May 2018 15:16:37 +1000
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Nicholas Piggin <npiggin@gmail.com> writes:

> Use the more refined and tested event polling loop from opal_put_chars
> as the fallback console flush in the opal-kmsg path. This loop is used
> by the console driver today, whereas the opal-kmsg fallback is not
> likely to have been used for years.
>
> Use WARN_ONCE rather than a printk when the fallback is invoked to
> prepare for moving the console flush into a common function.

Do we want to add a WARN in that path? If we're panicking things might
get worse if we WARN (which takes a trap).

cheers