From: "John W. Linville" <linville@xxxxxxxxxxxxx>
Date: Fri, 5 Jun 2009 14:50:48 -0400
> On Fri, Jun 05, 2009 at 07:29:07PM +0200, Michael Buesch wrote:
>> On Friday 05 June 2009 14:25:03 John W. Linville wrote:
>> > On Thu, Jun 04, 2009 at 11:18:33PM +0200, Michael Buesch wrote:
>> > > From: Matthieu CASTET <castet.matthieu@xxxxxxx>
>> > >
>> > > Fix possible unaligned u32 access in b43_generate_plcp_hdr().
>> > > Unaligned data is read/write with a u32 pointer instead of using the
>> > > packed structure. Some versions of gcc ignore the "packed" attribute, if the
>> > > structure element is accessed through a local pointer.
>> > >
>> > > Signed-off-by: Matthieu CASTET <castet.matthieu@xxxxxxx>
>> > > Signed-off-by: Michael Buesch <mb@xxxxxxxxx>
>> >
>> > That seems pretty brain-dead...can you cite a source for this
>> > information? The patch seems like a no-op...
>> >
>> > John
>>
>> struct foo {
>> int data;
>> } __attribute__((packed));
>>
>> struct foo foo;
>> int *d = &foo->data;
>> foo->data = x; /* Works for unaligned */
>> *d = y; /* Does not work for unaligned */
>
> Why not?
Because "int *" does not have the packed attribute.
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
