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Subject: Re: [PATCH] powerpc: Apply early paca fixups to boot_paca and the
 boot cpu's paca
From: Geoff Levand <geoff@infradead.org>
To: Michael Ellerman <michael@ellerman.id.au>
Date: Wed, 13 Feb 2013 16:57:22 -0800
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On Wed, 2013-02-13 at 11:44 +1100, Michael Ellerman wrote:
> In commit 466921c we added a hack to set the paca data_offset to zero so
> that per-cpu accesses would work on the boot cpu prior to per-cpu areas
> being setup. This fixed a problem with lockdep touching per-cpu areas
> very early in boot.
> 
> However if we combine CONFIG_LOCK_STAT=y with any of the PPC_EARLY_DEBUG
> options, we can hit the same problem in udbg_early_init(). To avoid that
> we need to set the data_offset of the boot_paca also. So factor out the
> fixup logic and call it for both the boot_paca, and "the paca of the
> boot cpu".
> 
> Signed-off-by: Michael Ellerman <michael@ellerman.id.au>

Tested-by: Geoff Levand <geoff@infradead.org>

This fixes a boot hang on the PS3 with ps3_defconfig builds of
linux-3.7.

Please consider applying for linux-3.7.x stable.

-Geoff