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| author | Qian Cai <cai@lca.pw> | 2019-03-05 15:50:11 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-03-05 21:07:21 -0800 |
| commit | d778015ac95bc036af73342c878ab19250e01fe1 (patch) | |
| tree | 17b01e3c16b0d9f38aba85f644af3689373c046e /mm/sparse.c | |
| parent | fc8efd2ddfed3f343c11b693e87140ff358d7ff5 (diff) | |
| download | lwn-d778015ac95bc036af73342c878ab19250e01fe1.tar.gz lwn-d778015ac95bc036af73342c878ab19250e01fe1.zip | |
mm/sparse: fix a bad comparison
next_present_section_nr() could only return an unsigned number -1, so
just check it specifically where compilers will convert -1 to unsigned
if needed.
mm/sparse.c: In function 'sparse_init_nid':
mm/sparse.c:200:20: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
((section_nr >= 0) && \
^~
mm/sparse.c:478:2: note: in expansion of macro
'for_each_present_section_nr'
for_each_present_section_nr(pnum_begin, pnum) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~
mm/sparse.c:200:20: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
((section_nr >= 0) && \
^~
mm/sparse.c:497:2: note: in expansion of macro
'for_each_present_section_nr'
for_each_present_section_nr(pnum_begin, pnum) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~
mm/sparse.c: In function 'sparse_init':
mm/sparse.c:200:20: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
((section_nr >= 0) && \
^~
mm/sparse.c:520:2: note: in expansion of macro
'for_each_present_section_nr'
for_each_present_section_nr(pnum_begin + 1, pnum_end) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~
Link: http://lkml.kernel.org/r/20190228181839.86504-1-cai@lca.pw
Fixes: c4e1be9ec113 ("mm, sparsemem: break out of loops early")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/sparse.c')
| -rw-r--r-- | mm/sparse.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/sparse.c b/mm/sparse.c index 7ea5dc6c6b19..77a0554fa5bd 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -197,7 +197,7 @@ static inline int next_present_section_nr(int section_nr) } #define for_each_present_section_nr(start, section_nr) \ for (section_nr = next_present_section_nr(start-1); \ - ((section_nr >= 0) && \ + ((section_nr != -1) && \ (section_nr <= __highest_present_section_nr)); \ section_nr = next_present_section_nr(section_nr)) |