Re: [PATCH stable 4.14] net: stmmac: Set dma ring length before enabling the DMA

[Greg KH <greg@kroah.com>]

On Mon, Apr 15, 2019 at 09:49:47AM +0200, Lars Persson wrote:
> This was fixed in upstream by commit 7d9e6c5afab6 ("net: stmmac: Integrate
> XGMAC into main driver flow") that is a new feature commit.
> 
> We found a race condition in the DMA init sequence that hits if the
> PHY already has link up during stmmac_hw_setup. Since the ring length
> was programmed after enabling the RX path, we might receive a packet
> before the correct ring length is programmed. When that happened we
> could not get reliable interrupts for DMA RX and the MTL complained
> about RX FIFO overrun.
> 
> Signed-off-by: Lars Persson <larper@axis.com>
> Cc: stable@vger.kernel.org # 4.14.x
> Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
> Cc: Alexandre Torgue <alexandre.torgue@st.com>
> Cc: Jose Abreu <joabreu@synopsys.com>
> ---
>  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

This, and the 4.9 patch now queued up, thanks.

greg k-h