El Thu, Aug 03, 2017 at 04:24:56PM +0300 Yury Norov ha dit: > On Wed, Aug 02, 2017 at 03:51:58PM -0700, Matthias Kaehlcke wrote: > > GENMASK_ULL performs a left-shift of (~0ULL), which technically > > results in an integer overflow. clang raises a warning about > > this if the overflow occurs in a preprocessor expression. To > > avoid the overflow first perform a right-shift to clear the > > bits that are shifted out. > > > > Signed-off-by: Matthias Kaehlcke <[email protected]> > > --- > > include/linux/bitops.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/include/linux/bitops.h b/include/linux/bitops.h > > index a83c822c35c2..21dfe63001e3 100644 > > --- a/include/linux/bitops.h > > +++ b/include/linux/bitops.h > > @@ -22,7 +22,7 @@ > > (((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h)))) > > Once you touche GENMASK_ULL, why not to fix also GENMASK.
Will do, thanks. Even though GENMASK_ULL can't be used (as is) to define the arm64 PAGE_OFFSET as initially intended it seems the change is still worthwhile since there are a few other preprocessor expressions using GENMASK_ULL.
