Left-shifting past the size of your datatype is undefined behaviour in C. The literal 34 gets the type `int`, and that one is not big enough to be left shifted by 26 bits. An `unsigned` is long enough (on any machine that has at least 32 bits for their ints.) For uniformity, we mark all the literals as unsigned. But it's only really needed for HUGETLB_FLAG_ENCODE_16GB. Thanks to Randy Dunlap for an initial review and suggestion.
Showing the changes to include/uapi (1 of 2 files). Show all
Unified · Split
| @@ -20,18 +20,18 @@ · 19 unmodified lines | |||
| 20 | #define HUGETLB_FLAG_ENCODE_SHIFT 26 | 20 | #define HUGETLB_FLAG_ENCODE_SHIFT 26 |
| 21 | #define HUGETLB_FLAG_ENCODE_MASK 0x3f | 21 | #define HUGETLB_FLAG_ENCODE_MASK 0x3f |
| 22 | 22 | ||
| 23 | #define HUGETLB_FLAG_ENCODE_16KB (14 << HUGETLB_FLAG_ENCODE_SHIFT) | 23 | #define HUGETLB_FLAG_ENCODE_16KB (14U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 24 | #define HUGETLB_FLAG_ENCODE_64KB (16 << HUGETLB_FLAG_ENCODE_SHIFT) | 24 | #define HUGETLB_FLAG_ENCODE_64KB (16U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 25 | #define HUGETLB_FLAG_ENCODE_512KB (19 << HUGETLB_FLAG_ENCODE_SHIFT) | 25 | #define HUGETLB_FLAG_ENCODE_512KB (19U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 26 | #define HUGETLB_FLAG_ENCODE_1MB (20 << HUGETLB_FLAG_ENCODE_SHIFT) | 26 | #define HUGETLB_FLAG_ENCODE_1MB (20U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 27 | #define HUGETLB_FLAG_ENCODE_2MB (21 << HUGETLB_FLAG_ENCODE_SHIFT) | 27 | #define HUGETLB_FLAG_ENCODE_2MB (21U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 28 | #define HUGETLB_FLAG_ENCODE_8MB (23 << HUGETLB_FLAG_ENCODE_SHIFT) | 28 | #define HUGETLB_FLAG_ENCODE_8MB (23U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 29 | #define HUGETLB_FLAG_ENCODE_16MB (24 << HUGETLB_FLAG_ENCODE_SHIFT) | 29 | #define HUGETLB_FLAG_ENCODE_16MB (24U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 30 | #define HUGETLB_FLAG_ENCODE_32MB (25 << HUGETLB_FLAG_ENCODE_SHIFT) | 30 | #define HUGETLB_FLAG_ENCODE_32MB (25U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 31 | #define HUGETLB_FLAG_ENCODE_256MB (28 << HUGETLB_FLAG_ENCODE_SHIFT) | 31 | #define HUGETLB_FLAG_ENCODE_256MB (28U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 32 | #define HUGETLB_FLAG_ENCODE_512MB (29 << HUGETLB_FLAG_ENCODE_SHIFT) | 32 | #define HUGETLB_FLAG_ENCODE_512MB (29U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 33 | #define HUGETLB_FLAG_ENCODE_1GB (30 << HUGETLB_FLAG_ENCODE_SHIFT) | 33 | #define HUGETLB_FLAG_ENCODE_1GB (30U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 34 | #define HUGETLB_FLAG_ENCODE_2GB (31 << HUGETLB_FLAG_ENCODE_SHIFT) | 34 | #define HUGETLB_FLAG_ENCODE_2GB (31U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 35 | #define HUGETLB_FLAG_ENCODE_16GB (34 << HUGETLB_FLAG_ENCODE_SHIFT) | 35 | #define HUGETLB_FLAG_ENCODE_16GB (34U << HUGETLB_FLAG_ENCODE_SHIFT) |
| 36 | 36 | ||
| 37 | #endif /* _ASM_GENERIC_HUGETLB_ENCODE_H_ */ | 37 | #endif /* _ASM_GENERIC_HUGETLB_ENCODE_H_ */ |