On 8/28/20 2:01 AM, kernel test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > head: 88abac0b753dfdd85362a26d2da8277cb1e0842b > commit: f464f9a6a06f2f521f78a6e1ac8680bca2e929e4 [3165/3717] device-dax: add an 'align' attribute > config: arm64-randconfig-r013-20200827 (attached as .config) > compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 71f3169e1baeff262583b35ef88f8fb6df7be85e) > reproduce (this is a W=1 build): > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > # install arm64 cross compiling tool for clang build > # apt-get install binutils-aarch64-linux-gnu > git checkout f464f9a6a06f2f521f78a6e1ac8680bca2e929e4 > # save the attached .config to linux build tree > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot <lkp@xxxxxxxxx> > > All warnings (new ones prefixed by >>): > > In file included from drivers/dax/super.c:18: >>> drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 68719476736 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] > if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) > ~~~~~ ^ ~~~~~~~~ > In file included from drivers/dax/bus.c:10: >>> drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 68719476736 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] > if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) > ~~~~~ ^ ~~~~~~~~ > 1 warning generated. > -- > In file included from drivers/dax/device.c:14: >>> drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 68719476736 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] > if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) > ~~~~~ ^ ~~~~~~~~ Despite HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD being x86 only, arm64 would still need the following fixup: device-dax-add-an-align-attribute-fix.patch: From: Joao Martins <joao.m.martins@xxxxxxxxxx> Date: Fri, 28 Aug 2020 11:33:14 -0400 Subject: [PATCH] device-dax: Fix dax_align_valid() to work on PAGE_SHIFT>=14 With ARM64_PAGE_SHIFT=14, we get: In file included from drivers/dax/device.c:14: drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 68719476736 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) ~~~~~ ^ ~~~~~~~~ In file included from drivers/dax/super.c:18: drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 68719476736 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) ~~~~~ ^ ~~~~~~~~ In file included from drivers/dax/bus.c:10: drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 68719476736 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) ~~~~~ ^ ~~~~~~~~ Or with ARM64_PAGE_SHIFT=16 && ARM64_VA_BITS_52=y: In file included from drivers/dax/device.c:14: drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 4398046511104 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) ~~~~~ ^ ~~~~~~~~ In file included from drivers/dax/super.c:18: drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 4398046511104 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) In file included from drivers/dax/bus.c:10: drivers/dax/dax-private.h:94:12: warning: result of comparison of constant 4398046511104 with expression of type 'unsigned int' is always false [-Wtautological-constant-out-of-range-compare] if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) ~~~~~ ^ ~~~~~~~~ Change dax_align_valid() to unsigned long (dax_align_valid() already is unsigned long). Note that in practice CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD is only set on x86, so a dax_align_valid(PUD_SIZE) check always return false. An alternative would be to invert the check to: if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) && align == PUD_SIZE) Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx> Link: https://lore.kernel.org/linux-mm/202008280906.WPrik7QQ%25lkp@xxxxxxxxx/ Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx> --- drivers/dax/dax-private.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index fe337436d7f5..1c974b7caae6 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -89,7 +89,7 @@ static inline struct dax_mapping *to_dax_mapping(struct device *dev) phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, unsigned long size); #ifdef CONFIG_TRANSPARENT_HUGEPAGE -static inline bool dax_align_valid(unsigned int align) +static inline bool dax_align_valid(unsigned long align) { if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) return true; @@ -100,7 +100,7 @@ static inline bool dax_align_valid(unsigned int align) return false; } #else -static inline bool dax_align_valid(unsigned int align) +static inline bool dax_align_valid(unsigned long align) { return align == PAGE_SIZE; } -- 2.17.1
