Re: linux-next: build failure after merge of the aio tree

[Benjamin LaHaise]

On Thu, Feb 04, 2016 at 04:17:42PM +0000, Russell King - ARM Linux wrote:
> On Thu, Feb 04, 2016 at 11:01:01AM -0500, Benjamin LaHaise wrote:
> > On Thu, Feb 04, 2016 at 02:39:07PM +0000, Russell King - ARM Linux wrote:
> > > However, this one should warn:
> > > 
> > > int test_wrong(char **v, const char **p)
> > > { return __get_user(*v, p); }
> > > 
> > > Good luck (I think you'll need lots of it to get a working solution)! :)
> > 
> > This works with your test cases on x86-32.  Note that it's only compile + 
> > link tested at present.
> 
> That's the easy bit!
> 
> The problem you're going to run into is here:
> 
> #define __get_user_nocheck(x, ptr, size)                                \
> ({                                                                      \
>         int __gu_err;                                                   \
>         unsigned long __gu_val;                                         \
>         __uaccess_begin();                                              \
>         __get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT);    \
>         __uaccess_end();                                                \
>         (x) = (__force __typeof__(*(ptr)))__gu_val;                     \
> 
> __gu_val will be 32-bit, even when you're wanting a 64-bit quantity.
> That's where the fun and games start...

Ugh.  You're making me install a 32 bit distro.....!

		-ben

> -- 
> RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
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