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Date: Fri, 27 Oct 2006 06:24:33 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: Stephen Rothwell <sfr@canb.auug.org.au>
cc: LKML <linux-kernel@vger.kernel.org>, ppc-dev <linuxppc-dev@ozlabs.org>,
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Subject: Re: [PATCH 2/3] Create compat_sys_migrate_pages
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On Fri, 27 Oct 2006, Stephen Rothwell wrote:

> No they aren't because they have compat routines that convert the bitmaps
> before calling the "normal" syscall.  They, importantly, only use
> compat_alloc_user_space once each.

Ah...

> > Fixing get_nodes() to do the proper thing would fix all of these
> > without having to touch sys_migrate_pages or creating a compat_ function
> > (which usually is placed in kernel/compat.c)
> 
> You need the compat_ version of the syscalls to know if you were called
> from a 32bit application in order to know if you may need to fixup the
> bitmaps that are passed from/to user mode.

The compat functions should be placed in kernel/compat.c next to 
compat_sys_move_pages.