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Subject: Re: hvc_console change results in corrupt oops output
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Anton Blanchard <anton@samba.org>
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Date: Mon, 04 Jul 2011 23:56:27 +1000
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On Mon, 2011-07-04 at 20:57 +1000, Anton Blanchard wrote:

 .../...

> The hypervisor gives us a busy return, so we could retry a number of
> times instead of dropping it on the floor. We'd need to do it in the
> hvc_console driver - the tty drivers share the same backend
> functions so we can't hide it in the pseries put_chars function.

For kernel console, I don't see why not wait forever ... If the
underlying backend really lost the connection it can always return a
negative error no ?

Or we could have "well defined" return codes for "wait forever" vs.
"drop this" ... maybe return -EAGAIN.

Cheers,
Ben.