Re: [RFC] [PATCH] Fix b43 driver build for arm

[Michael Buesch <mb@bu3sch.de>]

On Saturday 23 February 2008 11:14:23 Gordon Farquharson wrote:
> On Fri, Feb 22, 2008 at 10:51 PM, Michael Buesch <mb@bu3sch.de> wrote:
> >  A big fat comment is something like that:
> >
> >  /* Explicit padding to support a broken sanity check in file2alias.c.
> >   * The check will compare the size of the structure in the kernel
> >   * object file to the userspace the kernel is compiled on.
> >   * This breaks on cross-compilation. This padding is a workaround
> >   * for this. */
> 
> ---
> 
> Align the members of the SSB device structure to a 32 bit boundary so
> that the b43 driver can be built for arm using a cross compiler. This
> alignment is required so that the test in scripts/mod/file2alias.c
> that checks that the size of the device ID type against the size of
> the section in the object file succeeds (see comment and
> http://lkml.org/lkml/2008/2/18/481 for explanation).
> 
> Signed-off-by: Gordon Farquharson <gordonfarquharson@gmail.com>

Acked-by: Michael Buesch <mb@bu3sch.de>

> ---
> 
> diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
> index 139d49d..208d49a 100644
> --- a/include/linux/mod_devicetable.h
> +++ b/include/linux/mod_devicetable.h
> @@ -351,7 +351,13 @@ struct sdio_device_id {
>  struct ssb_device_id {
>  	__u16	vendor;
>  	__u16	coreid;
> -	__u8	revision;
> +	/* Explicit padding to support a broken sanity check in file2alias.c.
> +	 * The check compares the size of the structure in the kernel
> +	 * object file to the size of the structure reported in userspace for
> +	 * the system on which the kernel is compiled. The check breaks on
> +	 * cross-compilation, and the padding is a workaround for this. */
> +	__u8	revision
> +		__attribute__((aligned(sizeof(__u32))));
>  };
>  #define SSB_DEVICE(_vendor, _coreid, _revision)  \
>  	{ .vendor = _vendor, .coreid = _coreid, .revision = _revision, }
> 



-- 
Greetings Michael.