The patch titled
Subject: mm/sparse: fix a bad comparison
has been added to the -mm tree. Its filename is
mm-sparse-fix-a-bad-comparison.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-sparse-fix-a-bad-comparison.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-sparse-fix-a-bad-comparison.patch
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------------------------------------------------------
From: Qian Cai <cai@xxxxxx>
Subject: 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@xxxxxx
Fixes: c4e1be9ec113 ("mm, sparsemem: break out of loops early")
Signed-off-by: Qian Cai <cai@xxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/sparse.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/sparse.c~mm-sparse-fix-a-bad-comparison
+++ a/mm/sparse.c
@@ -197,7 +197,7 @@ static inline int next_present_section_n
}
#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))
_
Patches currently in -mm which might be from cai@xxxxxx are
page_poison-play-nicely-with-kasan.patch
slab-kmemleak-no-scan-alien-caches.patch
slub-remove-an-unused-addr-argument.patch
mm-compaction-be-selective-about-what-pageblocks-to-clear-skip-hints-fix.patch
mm-hotplug-fix-an-imbalance-with-debug_pagealloc.patch
mm-sparse-fix-a-bad-comparison.patch
signal-allow-the-null-signal-in-rt_sigqueueinfo.patch
