As explained by the comment, we don't strictly need this at moment, but, say, if in future, we decide to save a memory copy in the ping reply code by reusing the receive buffer for transmission, it would work for all interfaces, except for DSA. Therefore, let's iron out this wrinkle. Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> --- drivers/net/dsa.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/net/dsa.c b/drivers/net/dsa.c index ccd7d8755035..e0bf079e4dbf 100644 --- a/drivers/net/dsa.c +++ b/drivers/net/dsa.c @@ -270,7 +270,14 @@ static int dsa_switch_register_edev(struct dsa_switch *ds, struct dsa_port *dp; dp = dsa_port_alloc(ds, dn, port); - dp->rx_buf = xmalloc(DSA_PKTSIZE); + + /* DMA is done on buffer in receive ring allocated by network + * driver. This is then copied into this buffer, so we don't + * strictly need to use dma_alloc() here, unlike ds->tx_buf. + * We do it anyway as we don't want DSA buffers to be subtly + * different to that of a directly used network interface. + */ + dp->rx_buf = dma_alloc(DSA_PKTSIZE); edev = &dp->edev; edev->priv = dp; -- 2.39.2
