Re: RFD: x32 ABI system call numbers

[H.J. Lu]

On Sat, Sep 3, 2011 at 10:16 AM,  <Valdis.Kletnieks@xxxxxx> wrote:
> On Sat, 03 Sep 2011 09:40:55 PDT, "H. Peter Anvin" said:
>> Valdis.Kletnieks@xxxxxx wrote:
>>
>> >On Sat, 03 Sep 2011 10:41:16 +0200, Arnd Bergmann said:
>> >
>> >(Admittedly, I'm tuning in late on this discussion, but...)
>> >
>> >> For the ioctl interface however, the __u64/__s64 type in the x32 ABI
>> >> must be defined with __attribute__((packed,aligned(4))) to match what
>> >> the kernel implements because it emulates the x86-32 ABI.
>> >
>> >Is this a cast-in-stone issue, or is it still not too late to change that?
>> >And if we change that, can we simplify anything?
>>
>> The complexity of changing that would be enormous.
>
> Oh, I know changing the x86-32 ABI is impossible - I meant changing the
> decision to emulate that ABI (as opposed to emulating the x86-64 ABI, or a
> variant thereof, or something else).  Or are we already commited to that
> route, even if we're still trying to figure out what syscalls to include?

We can't use 64bit ioctl for x32 if indirect pointers are ever passed
to ioctl.


-- 
H.J.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/