From: Martin Habets habetsm.xilinx@gmail.com
[ Upstream commit 458f5d92df4807e2a7c803ed928369129996bf96 ]
When the page_ring is not used page_ptr_mask is 0. Do not dereference page_ring[0] in this case.
Fixes: 2768935a4660 ("sfc: reuse pages to avoid DMA mapping/unmapping costs") Reported-by: Taehee Yoo ap420073@gmail.com Signed-off-by: Martin Habets habetsm.xilinx@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/sfc/rx_common.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/net/ethernet/sfc/rx_common.c b/drivers/net/ethernet/sfc/rx_common.c index 633ca77a26fd..b925de9b4302 100644 --- a/drivers/net/ethernet/sfc/rx_common.c +++ b/drivers/net/ethernet/sfc/rx_common.c @@ -166,6 +166,9 @@ static void efx_fini_rx_recycle_ring(struct efx_rx_queue *rx_queue) struct efx_nic *efx = rx_queue->efx; int i;
+ if (unlikely(!rx_queue->page_ring)) + return; + /* Unmap and release the pages in the recycle ring. Remove the ring. */ for (i = 0; i <= rx_queue->page_ptr_mask; i++) { struct page *page = rx_queue->page_ring[i];