Add missing parentheses around use of macro argument "pos" in those
patterns to ensure operator precedence behaves as expected:
- typeof(*pos)
- pos->member
This corrects the following usage pattern where operator precedence is
unexpected:
LIST_HEAD(testlist);
struct test {
struct list_head node;
int a;
};
// pos->member issue
void f(void)
{
struct test *t1;
struct test **t2 = &t1;
list_for_each_entry_rcu((*t2), &testlist, node) { /* works */
//...
}
list_for_each_entry_rcu(*t2, &testlist, node) { /* broken */
//...
}
}
The typeof(*pos) lack of parentheses around "pos" is not an issue per se
in the specific macros modified here because "pos" is used as an lvalue,
which should prevent use of any operator causing issue. Still add the
extra parentheses for consistency.
Signed-off-by: Mathieu Desnoyers <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Neeraj Upadhyay <[email protected]>
Cc: Joel Fernandes <[email protected]>
Cc: Josh Triplett <[email protected]>
Cc: Boqun Feng <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Lai Jiangshan <[email protected]>
Cc: Zqiang <[email protected]>
Cc: [email protected]
Cc: [email protected]
---
include/linux/rculist.h | 28 ++++++++++++++--------------
1 file changed, 14 insertions(+), 14 deletions(-)
diff --git a/include/linux/rculist.h b/include/linux/rculist.h
index d29740be4833..d27aeff5447d 100644
--- a/include/linux/rculist.h
+++ b/include/linux/rculist.h
@@ -388,9 +388,9 @@ static inline void list_splice_tail_init_rcu(struct list_head *list,
*/
#define list_for_each_entry_rcu(pos, head, member, cond...) \
for (__list_check_rcu(dummy, ## cond, 0), \
- pos = list_entry_rcu((head)->next, typeof(*pos), member); \
- &pos->member != (head); \
- pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
+ pos = list_entry_rcu((head)->next, typeof(*(pos)), member);\
+ &(pos)->member != (head); \
+ pos = list_entry_rcu((pos)->member.next, typeof(*(pos)), member))
/**
* list_for_each_entry_srcu - iterate over rcu list of given type
@@ -407,9 +407,9 @@ static inline void list_splice_tail_init_rcu(struct list_head *list,
*/
#define list_for_each_entry_srcu(pos, head, member, cond) \
for (__list_check_srcu(cond), \
- pos = list_entry_rcu((head)->next, typeof(*pos), member); \
- &pos->member != (head); \
- pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
+ pos = list_entry_rcu((head)->next, typeof(*(pos)), member);\
+ &(pos)->member != (head); \
+ pos = list_entry_rcu((pos)->member.next, typeof(*(pos)), member))
/**
* list_entry_lockless - get the struct for this entry
@@ -441,9 +441,9 @@ static inline void list_splice_tail_init_rcu(struct list_head *list,
* but never deleted.
*/
#define list_for_each_entry_lockless(pos, head, member) \
- for (pos = list_entry_lockless((head)->next, typeof(*pos), member); \
- &pos->member != (head); \
- pos = list_entry_lockless(pos->member.next, typeof(*pos), member))
+ for (pos = list_entry_lockless((head)->next, typeof(*(pos)), member); \
+ &(pos)->member != (head); \
+ pos = list_entry_lockless((pos)->member.next, typeof(*(pos)), member))
/**
* list_for_each_entry_continue_rcu - continue iteration over list of given type
@@ -464,9 +464,9 @@ static inline void list_splice_tail_init_rcu(struct list_head *list,
* position.
*/
#define list_for_each_entry_continue_rcu(pos, head, member) \
- for (pos = list_entry_rcu(pos->member.next, typeof(*pos), member); \
- &pos->member != (head); \
- pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
+ for (pos = list_entry_rcu((pos)->member.next, typeof(*(pos)), member); \
+ &(pos)->member != (head); \
+ pos = list_entry_rcu((pos)->member.next, typeof(*(pos)), member))
/**
* list_for_each_entry_from_rcu - iterate over a list from current point
@@ -486,8 +486,8 @@ static inline void list_splice_tail_init_rcu(struct list_head *list,
* after the given position.
*/
#define list_for_each_entry_from_rcu(pos, head, member) \
- for (; &(pos)->member != (head); \
- pos = list_entry_rcu(pos->member.next, typeof(*(pos)), member))
+ for (; &(pos)->member != (head); \
+ pos = list_entry_rcu((pos)->member.next, typeof(*(pos)), member))
/**
* hlist_del_rcu - deletes entry from hash list without re-initialization
--
2.25.1