This is a note to let you know that I've just added the patch titled net: stmmac: fix completely hung TX when using TSO to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-stmmac-fix-completely-hung-tx-when-using-tso.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Jun 8 08:58:26 CEST 2017 From: Niklas Cassel <niklas.cassel@xxxxxxxx> Date: Tue, 6 Jun 2017 09:25:00 +0200 Subject: net: stmmac: fix completely hung TX when using TSO 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; Patches currently in stable-queue which might be from niklas.cassel@xxxxxxxx are queue-4.9/net-stmmac-fix-completely-hung-tx-when-using-tso.patch