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Date: Tue, 6 Nov 2012 14:13:07 -0600
From: Scott Wood <scottwood@freescale.com>
Subject: Re: powerpc: Don't silently handle machine checks from userspace
To: Micha Nelissen <micha.nelissen@Prodrive.nl>
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 (from micha.nelissen@Prodrive.nl on Tue Nov  6 10:43:19 2012)
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Cc: Martijn de Gouw <martijn.de.gouw@Prodrive.nl>,
 "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
 Anton Blanchard <anton@samba.org>
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On 11/06/2012 10:43:19 AM, Micha Nelissen wrote:
> From: Scott Wood [mailto:scottwood@freescale.com]
> >> Hmm I guess there is no simple solution then, since the "recover"
> >> function also prints the kernel messages about the machine check
> >> being in kernel mode without having checked whether it really was =20
> in
> >> kernel mode. In the past the user mode check was in between.
> >
> > It shouldn't be that difficult to make it say "in user mode" or "in
> > kernel mode" depending on which it was... or just remove that phrase
> > altogether and let the following output indicate whether it was in
> > kernel mode.
>=20
> Well printing the correct message is only part of it: do "we" want to =20
> pass guarded load errors (RapidIO bus errors) to user space or not?

Yes.

> And if we pass them, should we print a kernel message at all?

Yes (but maybe ratelimited).

-Scott=