Re: [PATCH v2 2/5] firmware: Basic dmi-sysfs support

[Tony Luck]

On Wed, Feb 23, 2011 at 12:28 PM, Mike Waychison <mikew@xxxxxxxxxx> wrote:
> Ya, I don't think there is anything that guarantees that dmi_header is
> aligned.   The access is probably the struct copy I did here:
>
>        /* Set the key */
>        entry->dh = *dh;

Yup - looking back at the assembly I see that one of the 2-byte
accesses is offset 2
(picking up ->handle), but the second is offset 0 (picking up ->type
and ->length). The
compiler assumed the structure was 2-byte aligned because of ->handle.

> What if we changed that guy to use memcpy?  We'd probably need to
> memcpy the dmi_system_event_log as well.  Patch attached (applies on
> top of the entire patchset).

With the patch, all the unaligned accesses go away.

Tested-by: Tony Luck <tony.luck@xxxxxxxxx>

-Tony
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