| Message ID | 1344752791-21140-1-git-send-email-yefremov.denis@gmail.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Sun, Aug 12, 2012 at 10:26:31AM +0400, Denis Efremov wrote: > rcu_dereference occurs in update section. Replacement by > rcu_dereference_protected in order to prevent lockdep > complaint. > > Found by Linux Driver Verification project (linuxtesting.org) > > Signed-off-by: Denis Efremov <yefremov.denis@gmail.com> > --- > drivers/net/macvtap.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c > index 0737bd4..0f0f9ce 100644 > --- a/drivers/net/macvtap.c > +++ b/drivers/net/macvtap.c > @@ -94,7 +94,8 @@ static int get_slot(struct macvlan_dev *vlan, struct macvtap_queue *q) > int i; > > for (i = 0; i < MAX_MACVTAP_QUEUES; i++) { > - if (rcu_dereference(vlan->taps[i]) == q) > + if (rcu_dereference_protected(vlan->taps[i], > + lockdep_is_held(&macvtap_lock)) == q) And now it's too long. Maybe a temporary would be better? struct macvtap_queue *t; t = rcu_dereference_protected(vlan->taps[i], lockdep_is_held(&macvtap_lock)); if (t == q) return i; ? Anyway - Acked-by: Michael S. Tsirkin <mst@redhat.com> > return i; > } > > -- > 1.7.7 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: "Michael S. Tsirkin" <mst@redhat.com> Date: Sun, 12 Aug 2012 11:49:29 +0300 > On Sun, Aug 12, 2012 at 10:26:31AM +0400, Denis Efremov wrote: >> rcu_dereference occurs in update section. Replacement by >> rcu_dereference_protected in order to prevent lockdep >> complaint. >> >> Found by Linux Driver Verification project (linuxtesting.org) >> >> Signed-off-by: Denis Efremov <yefremov.denis@gmail.com> ... > Acked-by: Michael S. Tsirkin <mst@redhat.com> Applied, thanks everyone. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 0737bd4..0f0f9ce 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -94,7 +94,8 @@ static int get_slot(struct macvlan_dev *vlan, struct macvtap_queue *q) int i; for (i = 0; i < MAX_MACVTAP_QUEUES; i++) { - if (rcu_dereference(vlan->taps[i]) == q) + if (rcu_dereference_protected(vlan->taps[i], + lockdep_is_held(&macvtap_lock)) == q) return i; }
rcu_dereference occurs in update section. Replacement by rcu_dereference_protected in order to prevent lockdep complaint. Found by Linux Driver Verification project (linuxtesting.org) Signed-off-by: Denis Efremov <yefremov.denis@gmail.com> --- drivers/net/macvtap.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)