Merge tag 'locking-urgent-2023-09-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Ingo Molnar:
 "Fix a include/linux/atomic/atomic-arch-fallback.h breakage that
  generated incorrect code, and fix a lockdep reporting race that may
  result in lockups"

* tag 'locking-urgent-2023-09-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/seqlock: Do the lockdep annotation before locking in do_write_seqcount_begin_nested()
  locking/atomic: scripts: fix fallback ifdeffery

Author: torvalds

include/linux/atomic/atomic-arch-fallback.h

@@ -459,8 +459,6 @@ raw_atomic_read_acquire(const atomic_t *v)
 {
 #if defined(arch_atomic_read_acquire)
 	return arch_atomic_read_acquire(v);
-#elif defined(arch_atomic_read)
-	return arch_atomic_read(v);
 #else
 	int ret;
 
@@ -508,8 +506,6 @@ raw_atomic_set_release(atomic_t *v, int i)
 {
 #if defined(arch_atomic_set_release)
 	arch_atomic_set_release(v, i);
-#elif defined(arch_atomic_set)
-	arch_atomic_set(v, i);
 #else
 	if (__native_word(atomic_t)) {
 		smp_store_release(&(v)->counter, i);
@@ -2575,8 +2571,6 @@ raw_atomic64_read_acquire(const atomic64_t *v)
 {
 #if defined(arch_atomic64_read_acquire)
 	return arch_atomic64_read_acquire(v);
-#elif defined(arch_atomic64_read)
-	return arch_atomic64_read(v);
 #else
 	s64 ret;
 
@@ -2624,8 +2618,6 @@ raw_atomic64_set_release(atomic64_t *v, s64 i)
 {
 #if defined(arch_atomic64_set_release)
 	arch_atomic64_set_release(v, i);
-#elif defined(arch_atomic64_set)
-	arch_atomic64_set(v, i);
 #else
 	if (__native_word(atomic64_t)) {
 		smp_store_release(&(v)->counter, i);
@@ -4657,4 +4649,4 @@ raw_atomic64_dec_if_positive(atomic64_t *v)
 }
 
 #endif /* _LINUX_ATOMIC_FALLBACK_H */
-// 202b45c7db600ce36198eb1f1fc2c2d5268ace2d
+// 2fdd6702823fa842f9cea57a002e6e4476ae780c

include/linux/seqlock.h

@@ -512,8 +512,8 @@ do {									\
 
 static inline void do_write_seqcount_begin_nested(seqcount_t *s, int subclass)
 {
-	do_raw_write_seqcount_begin(s);
 	seqcount_acquire(&s->dep_map, subclass, 0, _RET_IP_);
+	do_raw_write_seqcount_begin(s);
 }
 
 /**

scripts/atomic/gen-atomic-fallback.sh

@@ -102,7 +102,7 @@ gen_proto_order_variant()
 	fi
 
 	# Allow ACQUIRE/RELEASE/RELAXED ops to be defined in terms of FULL ops
-	if [ ! -z "${order}" ]; then
+	if [ ! -z "${order}" ] && ! meta_is_implicitly_relaxed "${meta}"; then
 		printf "#elif defined(arch_${basename})\n"
 		printf "\t${retstmt}arch_${basename}(${args});\n"
 	fi