From: Mohammad Shehar Yaar Tausif <sheharyaar48@xxxxxxxxx>
The original function call passed size of smap->bucket before the number of
buckets which raises the error 'calloc-transposed-args' on compilation.
Vlastimil Babka added:
The order of parameters can be traced back all the way to 6ac99e8f23d4
("bpf: Introduce bpf sk local storage") accross several refactorings,
and that's why the commit is used as a Fixes: tag.
In v6.10-rc1, a different commit 2c321f3f70bc ("mm: change inlined
allocation helpers to account at the call site") however exposed the
order of args in a way that gcc-14 has enough visibility to start
warning about it, because (in !CONFIG_MEMCG case) bpf_map_kvcalloc is
then a macro alias for kvcalloc instead of a static inline wrapper.
To sum up the warning happens when the following conditions are all met:
- gcc-14 is used (didn't see it with gcc-13)
- commit 2c321f3f70bc is present
- CONFIG_MEMCG is not enabled in .config
- CONFIG_WERROR turns this from a compiler warning to error
Fixes: 6ac99e8f23d4 ("bpf: Introduce bpf sk local storage")
Reviewed-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Signed-off-by: Mohammad Shehar Yaar Tausif <sheharyaar48@xxxxxxxxx>
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
---
kernel/bpf/bpf_local_storage.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
index 976cb258a0ed..c938dea5ddbf 100644
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -782,8 +782,8 @@ bpf_local_storage_map_alloc(union bpf_attr *attr,
nbuckets = max_t(u32, 2, nbuckets);
smap->bucket_log = ilog2(nbuckets);
- smap->buckets = bpf_map_kvcalloc(&smap->map, sizeof(*smap->buckets),
- nbuckets, GFP_USER | __GFP_NOWARN);
+ smap->buckets = bpf_map_kvcalloc(&smap->map, nbuckets,
+ sizeof(*smap->buckets), GFP_USER | __GFP_NOWARN);
if (!smap->buckets) {
err = -ENOMEM;
goto free_smap;
--
2.45.2
