6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Petr Tesarik <petr@xxxxxxxxxxx>
[ Upstream commit 38a15d0a50e0a43778561a5861403851f0b0194c ]
Fix bogus lockdep warnings if multiple u64_stats_sync variables are
initialized in the same file.
With CONFIG_LOCKDEP, seqcount_init() is a macro which declares:
static struct lock_class_key __key;
Since u64_stats_init() is a function (albeit an inline one), all calls
within the same file end up using the same instance, effectively treating
them all as a single lock-class.
Fixes: 9464ca650008 ("net: make u64_stats_init() a function")
Closes: https://lore.kernel.org/netdev/ea1567d9-ce66-45e6-8168-ac40a47d1821@xxxxxxxxxxxx/
Signed-off-by: Petr Tesarik <petr@xxxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240404075740.30682-1-petr@xxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/linux/u64_stats_sync.h | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/include/linux/u64_stats_sync.h b/include/linux/u64_stats_sync.h
index 46040d66334a8..79c3bbaa7e13e 100644
--- a/include/linux/u64_stats_sync.h
+++ b/include/linux/u64_stats_sync.h
@@ -135,10 +135,11 @@ static inline void u64_stats_inc(u64_stats_t *p)
p->v++;
}
-static inline void u64_stats_init(struct u64_stats_sync *syncp)
-{
- seqcount_init(&syncp->seq);
-}
+#define u64_stats_init(syncp) \
+ do { \
+ struct u64_stats_sync *__s = (syncp); \
+ seqcount_init(&__s->seq); \
+ } while (0)
static inline void __u64_stats_update_begin(struct u64_stats_sync *syncp)
{
--
2.43.0
