From mboxrd@z Thu Jan  1 00:00:00 1970
From: will.deacon@arm.com (Will Deacon)
Date: Tue, 8 Jul 2014 10:30:24 +0100
Subject: [PATCH resend] arm64: dmi: Add SMBIOS/DMI support
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 <20140708091513.GC8235@arm.com>
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To: linux-arm-kernel@lists.infradead.org
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On Tue, Jul 08, 2014 at 10:27:06AM +0100, Ard Biesheuvel wrote:
> On 8 July 2014 11:15, Will Deacon <will.deacon@arm.com> wrote:
> > On Tue, Jul 08, 2014 at 09:55:53AM +0100, Ard Biesheuvel wrote:
> >> > +#include <linux/slab.h>
> >> > +#include <linux/efi.h>
> >> > +
> >> > +/* Use efi mappings for DMI */
> >> > +#define dmi_early_remap(x, l)          efi_lookup_mapped_addr(x)
> >
> > Throwing away the length doesn't feel right, especially since the efi map
> > *does* have a size field.
> >
> 
> The thing to realize here is that, instead of doing actual ioremap()
> or early_ioremap() calls, we just reuse an existing EFI mapping here.
> (On x86, DMI/SMBIOS and EFI are not as tightly coupled, whereas on
> arm64, the former implies the latter). So would you prefer some kind
> of test against the size of the mapping before doing that?

Yeah, might not be a bad idea. Even if the thing happens to work by
construction, we still have an API that takes a size, so checking it's what
we have mapped sounds sensible.

Will