@@ -1089,13 +1089,10 @@ static bool qede_rx_xdp(struct qede_dev *edev,
xdp_prepare_buff(&xdp, page_address(bd->data), *data_offset,
*len, false);
- /* Queues always have a full reset currently, so for the time
- * being until there's atomic program replace just mark read
- * side for map helpers.
+ /* This code is invoked within a single NAPI poll cycle and thus under
+ * local_bh_disable(), which provides the needed RCU protection.
*/
- rcu_read_lock();
act = bpf_prog_run_xdp(prog, &xdp);
- rcu_read_unlock();
/* Recalculate, as XDP might have changed the headers */
*data_offset = xdp.data - xdp.data_hard_start;
The qede driver has rcu_read_lock()/rcu_read_unlock() pairs around XDP program invocations. However, the actual lifetime of the objects referred by the XDP program invocation is longer, all the way through to the call to xdp_do_flush(), making the scope of the rcu_read_lock() too small. This turns out to be harmless because it all happens in a single NAPI poll cycle (and thus under local_bh_disable()), but it makes the rcu_read_lock() misleading. Rather than extend the scope of the rcu_read_lock(), just get rid of it entirely. With the addition of RCU annotations to the XDP_REDIRECT map types that take bh execution into account, lockdep even understands this to be safe, so there's really no reason to keep it around. Cc: Ariel Elior <aelior@marvell.com> Cc: GR-everest-linux-l2@marvell.com Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> --- drivers/net/ethernet/qlogic/qede/qede_fp.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)