Le 10/02/2020 à 06:35, Anshuman Khandual a écrit :
On 02/10/2020 10:22 AM, Andrew Morton wrote:
On Thu, 6 Feb 2020 13:49:35 +0530 Anshuman Khandual <anshuman.khandual@xxxxxxx> wrote:
On 02/06/2020 04:40 AM, kbuild test robot wrote:
Hi Anshuman,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on powerpc/next]
[also build test ERROR on s390/features linus/master arc/for-next v5.5]
[cannot apply to mmotm/master tip/x86/core arm64/for-next/core next-20200205]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Anshuman-Khandual/mm-debug-Add-tests-validating-architecture-page-table-helpers/20200205-215507
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: ia64-allmodconfig (attached as .config)
compiler: ia64-linux-gcc (GCC) 7.5.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
GCC_VERSION=7.5.0 make.cross ARCH=ia64
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@xxxxxxxxx>
All error/warnings (new ones prefixed by >>):
In file included from include/asm-generic/pgtable-nopud.h:8:0,
from arch/ia64/include/asm/pgtable.h:586,
from include/linux/mm.h:99,
from include/linux/highmem.h:8,
from mm/debug_vm_pgtable.c:14:
mm/debug_vm_pgtable.c: In function 'pud_clear_tests':
include/asm-generic/pgtable-nop4d-hack.h:47:32: error: implicit declaration of function '__pgd'; did you mean '__p4d'? [-Werror=implicit-function-declaration]
#define __pud(x) ((pud_t) { __pgd(x) })
^
mm/debug_vm_pgtable.c:141:8: note: in expansion of macro '__pud'
pud = __pud(pud_val(pud) | RANDOM_ORVALUE);
^~~~~
include/asm-generic/pgtable-nop4d-hack.h:47:22: warning: missing braces around initializer [-Wmissing-braces]
#define __pud(x) ((pud_t) { __pgd(x) })
^
mm/debug_vm_pgtable.c:141:8: note: in expansion of macro '__pud'
pud = __pud(pud_val(pud) | RANDOM_ORVALUE);
^~~~~
cc1: some warnings being treated as errors
This build failure is expected now given that we have allowed DEBUG_VM_PGTABLE
with EXPERT without platform requiring ARCH_HAS_DEBUG_VM_PGTABLE. This problem
i.e build failure caused without a platform __pgd(), is known to exist both on
ia64 and arm (32bit) platforms. Please refer https://lkml.org/lkml/2019/9/24/314
for details where this was discussed earlier.
I'd prefer not to merge a patch which is known to cause build
regressions. Is there some temporary thing we can do to prevent these
errors until arch maintainers(?) get around to implementing the
long-term fixes?
We could explicitly disable CONFIG_DEBUG_VM_PGTABLE on ia64 and arm platforms
which will ensure that others can still use the EXPERT path.
config DEBUG_VM_PGTABLE
bool "Debug arch page table for semantics compliance"
depends on MMU
depends on !(IA64 || ARM)
depends on ARCH_HAS_DEBUG_VM_PGTABLE || EXPERT
default n if !ARCH_HAS_DEBUG_VM_PGTABLE
default y if DEBUG_VM
On both ia32 and arm, the fix is trivial.
Can we include the fix within this patch, just the same way as the
mm_p4d_folded() fix for x86 ?
Christophe
