[merged] bitops-avoid-integer-overflow-in-genmask_ull.patch removed from -mm tree

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The patch titled
     Subject: bitops: avoid integer overflow in GENMASK(_ULL)
has been removed from the -mm tree.  Its filename was
     bitops-avoid-integer-overflow-in-genmask_ull.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Subject: bitops: avoid integer overflow in GENMASK(_ULL)

GENMASK(_ULL) performs a left-shift of ~0UL(L), which technically results
in an integer overflow.  clang raises a warning if the overflow occurs in
a preprocessor expression.  Clear the low-order bits through a
substraction instead of the left-shift to avoid the overflow.

(akpm: no change in .text size in my testing)

Link: http://lkml.kernel.org/r/20170803212020.24939-1-mka@xxxxxxxxxxxx
Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 include/linux/bitops.h |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff -puN include/linux/bitops.h~bitops-avoid-integer-overflow-in-genmask_ull include/linux/bitops.h
--- a/include/linux/bitops.h~bitops-avoid-integer-overflow-in-genmask_ull
+++ a/include/linux/bitops.h
@@ -19,10 +19,11 @@
  * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
  */
 #define GENMASK(h, l) \
-	(((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h))))
+	(((~0UL) - (1UL << (l)) + 1) & (~0UL >> (BITS_PER_LONG - 1 - (h))))
 
 #define GENMASK_ULL(h, l) \
-	(((~0ULL) << (l)) & (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h))))
+	(((~0ULL) - (1ULL << (l)) + 1) & \
+	 (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h))))
 
 extern unsigned int __sw_hweight8(unsigned int w);
 extern unsigned int __sw_hweight16(unsigned int w);
_

Patches currently in -mm which might be from mka@xxxxxxxxxxxx are


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