[PATCH tip/core/urgent 3/3] idr: fix RCU lockdep splat in idr_get_next()

From: Paul E. McKenney
Date: Tue Jun 15 2010 - 18:29:55 EST


Convert to rcu_dereference_raw() given that many callers may have many
different locking models.

Located-by: Miles Lane <miles.lane@xxxxxxxxx>
Tested-by: Miles Lane <miles.lane@xxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
lib/idr.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/idr.c b/lib/idr.c
index c1a2069..7f1a4f0 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -602,7 +602,7 @@ void *idr_get_next(struct idr *idp, int *nextidp)
/* find first ent */
n = idp->layers * IDR_BITS;
max = 1 << n;
- p = rcu_dereference(idp->top);
+ p = rcu_dereference_raw(idp->top);
if (!p)
return NULL;

@@ -610,7 +610,7 @@ void *idr_get_next(struct idr *idp, int *nextidp)
while (n > 0 && p) {
n -= IDR_BITS;
*paa++ = p;
- p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]);
+ p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]);
}

if (p) {
--
1.7.0.6

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