kernel build bot showed a warning triggered by commit
76695af20c01 ("locking, arch: use WRITE_ONCE()/READ_ONCE() in
smp_store_release()/smp_load_acquire()"). Turns out that sparse
does not like WRITE_ONCE accessing elements from the (sparse)
rcu address space.fs/afs/inode.c:448:9: sparse: incorrect type in initializer (different address spaces) fs/afs/inode.c:448:9: expected struct afs_permits *__val fs/afs/inode.c:448:9: got void [noderef] <asn:4>*<noident> Solution is to force cast away the sparse attributes for the initializer of the union in WRITE_SAME. As this now gets too long, lets split the macro. Signed-off-by: Christian Borntraeger <[email protected]> --- include/linux/compiler.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/include/linux/compiler.h b/include/linux/compiler.h index e08a6ae..c836eb2 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -252,7 +252,12 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s ({ union { typeof(x) __val; char __c[1]; } __u; __read_once_size(&(x), __u.__c, sizeof(x)); __u.__val; }) #define WRITE_ONCE(x, val) \ - ({ union { typeof(x) __val; char __c[1]; } __u = { .__val = (val) }; __write_once_size(&(x), __u.__c, sizeof(x)); __u.__val; }) +({ \ + union { typeof(x) __val; char __c[1]; } __u = \ + { .__val = (__force typeof(x)) (val) }; \ + __write_once_size(&(x), __u.__c, sizeof(x)); \ + __u.__val; \ +}) /** * READ_ONCE_CTRL - Read a value heading a control dependency -- 2.3.8 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
