summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorYASUAKI ISHIMATSU <yasu.isimatu@gmail.com>2017-10-03 16:16:29 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-10-03 17:54:25 -0700
commit1dd2bfc86818ddbc95f98e312e7704350223fd7d (patch)
tree394d0f26cd302875089057232dca4c13fd4c82de
parentc9653850c90d6050197bc76ba672e00a7771aea5 (diff)
downloadlinux-1dd2bfc86818ddbc95f98e312e7704350223fd7d.tar.bz2
mm/memory_hotplug: change pfn_to_section_nr/section_nr_to_pfn macro to inline function
pfn_to_section_nr() and section_nr_to_pfn() are defined as macro. pfn_to_section_nr() has no issue even if it is defined as macro. But section_nr_to_pfn() has overflow issue if sec is defined as int. section_nr_to_pfn() just shifts sec by PFN_SECTION_SHIFT. If sec is defined as unsigned long, section_nr_to_pfn() returns pfn as 64 bit value. But if sec is defined as int, section_nr_to_pfn() returns pfn as 32 bit value. __remove_section() calculates start_pfn using section_nr_to_pfn() and scn_nr defined as int. So if hot-removed memory address is over 16TB, overflow issue occurs and section_nr_to_pfn() does not calculate correct pfn. To make callers use proper arg, the patch changes the macros to inline functions. Fixes: 815121d2b5cd ("memory_hotplug: clear zone when removing the memory") Link: http://lkml.kernel.org/r/e643a387-e573-6bbf-d418-c60c8ee3d15e@gmail.com Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Reza Arbab <arbab@linux.vnet.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--include/linux/mmzone.h10
-rw-r--r--mm/memory_hotplug.c2
2 files changed, 9 insertions, 3 deletions
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 356a814e7c8e..c8f89417740b 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1094,8 +1094,14 @@ static inline unsigned long early_pfn_to_nid(unsigned long pfn)
#error Allocator MAX_ORDER exceeds SECTION_SIZE
#endif
-#define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
-#define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
+static inline unsigned long pfn_to_section_nr(unsigned long pfn)
+{
+ return pfn >> PFN_SECTION_SHIFT;
+}
+static inline unsigned long section_nr_to_pfn(unsigned long sec)
+{
+ return sec << PFN_SECTION_SHIFT;
+}
#define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
#define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 23d5bd968950..efd1ad37bb57 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -551,7 +551,7 @@ static int __remove_section(struct zone *zone, struct mem_section *ms,
return ret;
scn_nr = __section_nr(ms);
- start_pfn = section_nr_to_pfn(scn_nr);
+ start_pfn = section_nr_to_pfn((unsigned long)scn_nr);
__remove_zone(zone, start_pfn);
sparse_remove_one_section(zone, ms, map_offset);