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=626...
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.