4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Niklas Cassel <niklas.cassel@xxxxxxxx> [ Upstream commit 426849e6611f2092553f8d53372ae310818a6292 ] stmmac_tso_allocator can fail to set the Last Descriptor bit on a descriptor that actually was the last descriptor. This happens when the buffer of the last descriptor ends up having a size of exactly TSO_MAX_BUFF_SIZE. When the IP eventually reaches the next last descriptor, which actually has the bit set, the DMA will hang. When the DMA hangs, we get a tx timeout, however, since stmmac does not do a complete reset of the IP in stmmac_tx_timeout, we end up in a state with completely hung TX. Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx> Acked-by: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx> Acked-by: Alexandre TORGUE <alexandre.torgue@xxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1953,7 +1953,7 @@ static void stmmac_tso_allocator(struct priv->hw->desc->prepare_tso_tx_desc(desc, 0, buff_size, 0, 1, - (last_segment) && (buff_size < TSO_MAX_BUFF_SIZE), + (last_segment) && (tmp_len <= TSO_MAX_BUFF_SIZE), 0, 0); tmp_len -= TSO_MAX_BUFF_SIZE;