[PATCH] mm/show_mem: fix format string inconsistencies and type mismatches
From: Ye Liu
Date: Tue Aug 04 2026 - 22:16:24 EST
From: Ye Liu <liuye@xxxxxxxxxx>
Fix five format string issues in show_free_areas() and __show_mem():
1-2. reserved_highatomic and free_highatomic: %luKB -> %lukB
The uppercase "KB" is inconsistent with all other fields in the
same output block and with /proc/meminfo convention.
3. local_pcp: %ukB -> %lukB with explicit (unsigned long) cast
per_cpu_pages.count is int, so K(count) yields int. Using %u
was a signed/unsigned mismatch. Cast to unsigned long and use
%lu for consistency with all other K() usages in the file.
4. total pagecache pages: %ld -> %lu
global_node_page_state() returns unsigned long. Using %ld is a
signedness mismatch caught by gcc -Wformat-signedness.
5. hwpoisoned pages: %lu -> %ld
atomic_long_read() returns long (signed). Using %lu is a
signedness mismatch caught by gcc -Wformat-signedness.
Verified with: make KCFLAGS="-Wformat -Wformat-signedness" mm/show_mem.o
Signed-off-by: Ye Liu <liuye@xxxxxxxxxx>
---
mm/show_mem.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/mm/show_mem.c b/mm/show_mem.c
index d1288b4c2b64..b938cbcd774a 100644
--- a/mm/show_mem.c
+++ b/mm/show_mem.c
@@ -309,8 +309,8 @@ static void show_free_areas(unsigned int filter, const nodemask_t *nodemask,
" min:%lukB"
" low:%lukB"
" high:%lukB"
- " reserved_highatomic:%luKB"
- " free_highatomic:%luKB"
+ " reserved_highatomic:%lukB"
+ " free_highatomic:%lukB"
" active_anon:%lukB"
" inactive_anon:%lukB"
" active_file:%lukB"
@@ -323,7 +323,7 @@ static void show_free_areas(unsigned int filter, const nodemask_t *nodemask,
" mlocked:%lukB"
" bounce:%lukB"
" free_pcp:%lukB"
- " local_pcp:%ukB"
+ " local_pcp:%lukB"
" free_cma:%lukB"
"\n",
zone->name,
@@ -350,7 +350,7 @@ static void show_free_areas(unsigned int filter, const nodemask_t *nodemask,
K(zone_page_state(zone, NR_MLOCK)),
0UL,
K(free_pcp),
- K(this_cpu_read(zone->per_cpu_pageset->count)),
+ K((unsigned long)this_cpu_read(zone->per_cpu_pageset->count)),
K(zone_page_state(zone, NR_FREE_CMA_PAGES)));
printk("lowmem_reserve[]:");
for (i = 0; i < MAX_NR_ZONES; i++)
@@ -400,7 +400,7 @@ static void show_free_areas(unsigned int filter, const nodemask_t *nodemask,
hugetlb_show_meminfo_node(nid);
}
- printk("%ld total pagecache pages\n", global_node_page_state(NR_FILE_PAGES));
+ printk("%lu total pagecache pages\n", global_node_page_state(NR_FILE_PAGES));
show_swap_cache_info();
}
@@ -430,7 +430,7 @@ void __show_mem(unsigned int filter, const nodemask_t *nodemask,
printk("%lu pages cma reserved\n", totalcma_pages);
#endif
#ifdef CONFIG_MEMORY_FAILURE
- printk("%lu pages hwpoisoned\n", atomic_long_read(&num_poisoned_pages));
+ printk("%ld pages hwpoisoned\n", atomic_long_read(&num_poisoned_pages));
#endif
#ifdef CONFIG_MEM_ALLOC_PROFILING
static DEFINE_SPINLOCK(mem_alloc_profiling_spinlock);
--
2.25.1