From mboxrd@z Thu Jan  1 00:00:00 1970
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Subject: RE: PTE entries
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Siva Prasad <sprasad@bivio.net>
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Date: Thu, 03 May 2007 08:12:46 +1000
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On Wed, 2007-05-02 at 12:58 -0700, Siva Prasad wrote:
> Hi Ben,
> 
> First, 
> Are there any other places where we have self modifying code in Linux
> kernel, other than in arch/powerpc/mm/ppc_mmu_32.c:MMU_init_hw()
> (basically modified create_hpte and flush_hash_page)

There is the cpu feature fixup code, there might also be something
around the SMP code.

> Second,
> Instead of using addis, why can't we move it from SDR1 register and mask
> the second half. SDR1 has the required value. Right?
> May be I am missing something here.

Would be slower. Accessing SPRs is slow.