Ping!
regards,
dan carpenter
On Thu, Apr 21, 2022 at 06:52:48PM +0300, Dan Carpenter wrote:
> Hello Horatiu Vultur,
>
> The patch 2ea1cbac267e: "net: lan966x: Update FDMA to change MTU."
> from Apr 8, 2022, leads to the following Smatch static checker
> warning:
>
> drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c:736 lan966x_fdma_reload()
> warn: 'rx_dcbs' was already freed.
>
> drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> 685 static int lan966x_fdma_reload(struct lan966x *lan966x, int new_mtu)
> 686 {
> 687 void *rx_dcbs, *tx_dcbs, *tx_dcbs_buf;
> 688 dma_addr_t rx_dma, tx_dma;
> 689 u32 size;
> 690 int err;
> 691
> 692 /* Store these for later to free them */
> 693 rx_dma = lan966x->rx.dma;
> 694 tx_dma = lan966x->tx.dma;
> 695 rx_dcbs = lan966x->rx.dcbs;
> 696 tx_dcbs = lan966x->tx.dcbs;
> 697 tx_dcbs_buf = lan966x->tx.dcbs_buf;
> 698
> 699 napi_synchronize(&lan966x->napi);
> 700 napi_disable(&lan966x->napi);
> 701 lan966x_fdma_stop_netdev(lan966x);
> 702
> 703 lan966x_fdma_rx_disable(&lan966x->rx);
> 704 lan966x_fdma_rx_free_pages(&lan966x->rx);
> 705 lan966x->rx.page_order = round_up(new_mtu, PAGE_SIZE) / PAGE_SIZE - 1;
> 706 err = lan966x_fdma_rx_alloc(&lan966x->rx);
> 707 if (err)
> 708 goto restore;
> 709 lan966x_fdma_rx_start(&lan966x->rx);
> 710
> 711 size = sizeof(struct lan966x_rx_dcb) * FDMA_DCB_MAX;
> 712 size = ALIGN(size, PAGE_SIZE);
> 713 dma_free_coherent(lan966x->dev, size, rx_dcbs, rx_dma);
> ^^^^^^^
> Freed
>
> 714
> 715 lan966x_fdma_tx_disable(&lan966x->tx);
> 716 err = lan966x_fdma_tx_alloc(&lan966x->tx);
> 717 if (err)
> 718 goto restore_tx;
> ^^^^^^^^^^^^^^^
>
> 719
> 720 size = sizeof(struct lan966x_tx_dcb) * FDMA_DCB_MAX;
> 721 size = ALIGN(size, PAGE_SIZE);
> 722 dma_free_coherent(lan966x->dev, size, tx_dcbs, tx_dma);
> 723
> 724 kfree(tx_dcbs_buf);
> 725
> 726 lan966x_fdma_wakeup_netdev(lan966x);
> 727 napi_enable(&lan966x->napi);
> 728
> 729 return err;
> 730 restore:
> 731 lan966x->rx.dma = rx_dma;
> 732 lan966x->tx.dma = tx_dma;
> 733 lan966x_fdma_rx_start(&lan966x->rx);
> 734
> 735 restore_tx:
> --> 736 lan966x->rx.dcbs = rx_dcbs;
> ^^^^^^^
>
> 737 lan966x->tx.dcbs = tx_dcbs;
> 738 lan966x->tx.dcbs_buf = tx_dcbs_buf;
> 739
> 740 return err;
> 741 }
>
> regards,
> dan carpenter
