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From: Paul Mackerras <paulus@samba.org>
To: Michael Ellerman <michael@ellerman.id.au>
Cc: linuxppc-dev@ozlabs.org, Arnd Bergmann <arnd.bergmann@de.ibm.com>
Subject: Re: [PATCH] Assume we're on cpu 0 in early boot
Date: Wed, 28 Jun 2006 11:42:01 +1000	[thread overview]
Message-ID: <17569.56937.308576.848377@cargo.ozlabs.ibm.com> (raw)
In-Reply-To: <20060627040036.469B767B28@ozlabs.org>

Michael Ellerman writes:

> There's a small period early in boot where we don't know which cpu we're
> running on. That's ok, except that it means we have no paca, or more
> correctly that our paca pointer points somewhere random.
> 
> So that we can safely call things like smp_processor_id(), we need a paca,
> so just assume we're on cpu 0. No code should _write_ to the paca before
> we've set the correct one up.

OK, but why not just do a setup_paca(0) at the start of early_setup(),
in C code?  You can also remove the redundant paca setting in
start_here_common() in head_64.S.

Paul.

  reply	other threads:[~2006-06-28  1:42 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-06-23  8:20 [PATCH 2/8] Assume we're on cpu 0 in early boot Michael Ellerman
2006-06-23 10:03 ` Jimi Xenidis
2006-06-27  4:00   ` [PATCH] " Michael Ellerman
2006-06-28  1:42     ` Paul Mackerras [this message]
2006-06-28  2:11       ` Michael Ellerman
2006-06-28  3:18       ` Michael Ellerman

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