Re: [PATCHv5, REBASED 9/9] x86/mm: Allow to have userspace mappings above 47-bits

On Mon, May 15, 2017 at 10:49:43PM +0800, kbuild test robot wrote:

Hi Kirill,

[auto build test ERROR on linus/master]
[also build test ERROR on v4.12-rc1 next-20170515]
[cannot apply to tip/x86/core xen-tip/linux-next]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Kirill-A-Shutemov/x86-5-level-paging-enabling-for-v4-12-Part-4/20170515-202736
config: i386-defconfig (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All error/warnings (new ones prefixed by >>):

   In file included from include/linux/cache.h:4:0,
                    from include/linux/printk.h:8,
                    from include/linux/kernel.h:13,
                    from mm/mmap.c:11:
   mm/mmap.c: In function 'arch_get_unmapped_area_topdown':
   arch/x86/include/asm/processor.h:878:50: error: 'TASK_SIZE_LOW' undeclared (first use in this function)
    #define TASK_UNMAPPED_BASE  __TASK_UNMAPPED_BASE(TASK_SIZE_LOW)

Thanks. Fixup is below.

Let me know if I need to send the full patch:

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index aaed58b03ddb..65663de9287b 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h

@@ -794,6 +794,7 @@ static inline void spin_lock_prefetch(const void *x)
  */
 #define IA32_PAGE_OFFSET	PAGE_OFFSET
 #define TASK_SIZE		PAGE_OFFSET
+#define TASK_SIZE_LOW		TASK_SIZE
 #define TASK_SIZE_MAX		TASK_SIZE
 #define DEFAULT_MAP_WINDOW	TASK_SIZE
 #define STACK_TOP		TASK_SIZE

-- 
 Kirill A. Shutemov