Le 22/06/2018 à 16:55, Mathieu Malaterre a écrit :
On Fri, Jun 22, 2018 at 3:49 PM Christophe Leroy <christophe.le...@c-s.fr> wrote:This patch fixes the following warnings (obtained with make W=1). arch/powerpc/mm/slice.c: In function 'slice_range_to_mask': arch/powerpc/mm/slice.c:73:12: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (start < SLICE_LOW_TOP) { ^ arch/powerpc/mm/slice.c:81:20: error: comparison is always false due to limited range of data type [-Werror=type-limits] if ((start + len) > SLICE_LOW_TOP) { ^ arch/powerpc/mm/slice.c: In function 'slice_mask_for_free': arch/powerpc/mm/slice.c:136:17: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (high_limit <= SLICE_LOW_TOP) ^ arch/powerpc/mm/slice.c: In function 'slice_check_range_fits': arch/powerpc/mm/slice.c:185:12: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (start < SLICE_LOW_TOP) { ^ arch/powerpc/mm/slice.c:195:39: error: comparison is always false due to limited range of data type [-Werror=type-limits] if (SLICE_NUM_HIGH && ((start + len) > SLICE_LOW_TOP)) { ^ arch/powerpc/mm/slice.c: In function 'slice_scan_available': arch/powerpc/mm/slice.c:306:11: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (addr < SLICE_LOW_TOP) { ^ arch/powerpc/mm/slice.c: In function 'get_slice_psize': arch/powerpc/mm/slice.c:709:11: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (addr < SLICE_LOW_TOP) { ^ Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> --- arch/powerpc/mm/slice.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c index 9530c6db406a..17c57760e06c 100644 --- a/arch/powerpc/mm/slice.c +++ b/arch/powerpc/mm/slice.c @@ -62,6 +62,13 @@ static void slice_print_mask(const char *label, const struct slice_mask *mask) { #endif +static inline bool slice_addr_is_low(unsigned long addr) +{ + u64 tmp = (u64)addr; + + return tmp < SLICE_LOW_TOP; +} + static void slice_range_to_mask(unsigned long start, unsigned long len, struct slice_mask *ret) { @@ -71,7 +78,7 @@ static void slice_range_to_mask(unsigned long start, unsigned long len, if (SLICE_NUM_HIGH) bitmap_zero(ret->high_slices, SLICE_NUM_HIGH); - if (start < SLICE_LOW_TOP) { + if (slice_addr_is_low(start)) { unsigned long mend = min(end, (unsigned long)(SLICE_LOW_TOP - 1)); @@ -79,7 +86,7 @@ static void slice_range_to_mask(unsigned long start, unsigned long len, - (1u << GET_LOW_SLICE_INDEX(start)); } - if ((start + len) > SLICE_LOW_TOP) { + if (!slice_addr_is_low(end)) { unsigned long start_index = GET_HIGH_SLICE_INDEX(start); unsigned long align_end = ALIGN(end, (1UL << SLICE_HIGH_SHIFT)); unsigned long count = GET_HIGH_SLICE_INDEX(align_end) - start_index; @@ -134,7 +141,7 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret, if (!slice_low_has_vma(mm, i)) ret->low_slices |= 1u << i; - if (high_limit <= SLICE_LOW_TOP) + if (slice_addr_is_low(high_limit - 1))Is high_limit ever going to be 0 ?
See slice_get_unmapped_area(), high_limit will never be 0. Christophe
return; for (i = 0; i < GET_HIGH_SLICE_INDEX(high_limit); i++) @@ -183,7 +190,7 @@ static bool slice_check_range_fits(struct mm_struct *mm, unsigned long end = start + len - 1; u64 low_slices = 0; - if (start < SLICE_LOW_TOP) { + if (slice_addr_is_low(start)) { unsigned long mend = min(end, (unsigned long)(SLICE_LOW_TOP - 1)); @@ -193,7 +200,7 @@ static bool slice_check_range_fits(struct mm_struct *mm, if ((low_slices & available->low_slices) != low_slices) return false; - if (SLICE_NUM_HIGH && ((start + len) > SLICE_LOW_TOP)) { + if (SLICE_NUM_HIGH && !slice_addr_is_low(end)) { unsigned long start_index = GET_HIGH_SLICE_INDEX(start); unsigned long align_end = ALIGN(end, (1UL << SLICE_HIGH_SHIFT)); unsigned long count = GET_HIGH_SLICE_INDEX(align_end) - start_index; @@ -304,7 +311,7 @@ static bool slice_scan_available(unsigned long addr, int end, unsigned long *boundary_addr) { unsigned long slice; - if (addr < SLICE_LOW_TOP) { + if (slice_addr_is_low(addr)) { slice = GET_LOW_SLICE_INDEX(addr); *boundary_addr = (slice + end) << SLICE_LOW_SHIFT; return !!(available->low_slices & (1u << slice)); @@ -707,7 +714,7 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr) VM_BUG_ON(radix_enabled()); - if (addr < SLICE_LOW_TOP) { + if (slice_addr_is_low(addr)) { psizes = mm->context.low_slices_psize; index = GET_LOW_SLICE_INDEX(addr); } else { -- 2.13.3
