ghes_estatus_caches should be add rcu annotation to avoid sparse warnings. drivers/acpi/apei/ghes.c:733:25: sparse: sparse: incompatible types in comparison expression (different address spaces): drivers/acpi/apei/ghes.c:733:25: sparse: struct ghes_estatus_cache [noderef] __rcu * drivers/acpi/apei/ghes.c:733:25: sparse: struct ghes_estatus_cache * drivers/acpi/apei/ghes.c:813:25: sparse: sparse: incompatible types in comparison expression (different address spaces): drivers/acpi/apei/ghes.c:813:25: sparse: struct ghes_estatus_cache [noderef] __rcu * drivers/acpi/apei/ghes.c:813:25: sparse: struct ghes_estatus_cache * unrcu_pointer is to strip the __rcu in cmpxchg. Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Jia He <justin.he@xxxxxxx> --- drivers/acpi/apei/ghes.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 4af269b22bd4..c0b09addb96f 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -153,7 +153,7 @@ struct ghes_vendor_record_entry { static struct gen_pool *ghes_estatus_pool; static unsigned long ghes_estatus_pool_size_request; -static struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE]; +static struct ghes_estatus_cache __rcu *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE]; static atomic_t ghes_estatus_cache_alloced; static int ghes_panic_timeout __read_mostly = 30; @@ -843,8 +843,9 @@ static void ghes_estatus_cache_add( } /* new_cache must be put into array after its contents are written */ smp_wmb(); - if (slot != -1 && cmpxchg(ghes_estatus_caches + slot, - slot_cache, new_cache) == slot_cache) { + if (slot != -1 && unrcu_pointer(cmpxchg(ghes_estatus_caches + slot, + RCU_INITIALIZER(slot_cache), + RCU_INITIALIZER(new_cache))) == slot_cache) { if (slot_cache) call_rcu(&slot_cache->rcu, ghes_estatus_cache_rcu_free); } else -- 2.25.1