[PATCH V2] ARM: mm: make UACCESS_WITH_MEMCPY huge page aware

[Steve Capper]

On Fri, Oct 11, 2013 at 10:57:51AM +0100, Russell King - ARM Linux wrote:
> On Wed, Sep 25, 2013 at 01:31:29PM +0100, Steve Capper wrote:
> > The memory pinning code in uaccess_with_memcpy.c does not check
> > for HugeTLB or THP pmds, and will enter an infinite loop should
> > a __copy_to_user or __clear_user occur against a huge page.
> 
> This patch causes a build error with certain configuration options:
> 
> arch/arm/lib/uaccess_with_memcpy.c: In function 'pin_page_for_write':
> arch/arm/lib/uaccess_with_memcpy.c:57:2: error: implicit declaration of function 'pmd_thp_or_huge'
> arch/arm/lib/uaccess_with_memcpy.c:60:3: error: implicit declaration of function 'pmd_hugewillfault'
> 
> found via a randconfig build, configuration:
> 
> http://www.arm.linux.org.uk/developer/build/file.php?type=config&idx=6265
> 
> > ---
> >  arch/arm/include/asm/pgtable-3level.h |  3 +++
> >  arch/arm/lib/uaccess_with_memcpy.c    | 41 ++++++++++++++++++++++++++++++++---
> >  2 files changed, 41 insertions(+), 3 deletions(-)
> 
> As the macros are in pgtable-3level.h, this won't work with any configuration
> using the 2level header file.

Hi Russell,
Apologies, that was careless rebasing on my part.

Would you like a fix for this, or should I send a new patch?

Thanks,
-- 
Steve