When FIFO reaches near full state, device will issue pause frame. If pause slot is enabled(set to 1), in this time, device will issue pause frame only once. But if pause slot is disabled(set to 0), device will keep sending pause frames until FIFO reaches near empty state.
When pause slot is disabled, if there is no one to handle receive packets, device FIFO will reach near full state and keep sending pause frames. That will impact entire local area network.
This issue can be reproduced in Chromebox (not Chromebook) in developer mode running a test image (and v5.10 kernel): 1) ping -f $CHROMEBOX (from workstation on same local network) 2) run "powerd_dbus_suspend" from command line on the $CHROMEBOX 3) ping $ROUTER (wait until ping fails from workstation)
Takes about ~20-30 seconds after step 2 for the local network to stop working.
Fix this issue by enabling pause slot to only send pause frame once when FIFO reaches near full state.
Fixes: f1bce4ad2f1c ("r8169: add support for RTL8125") Reported-by: Grant Grundler grundler@chromium.org Tested-by: Grant Grundler grundler@chromium.org Cc: stable@vger.kernel.org Signed-off-by: ChunHao Lin hau@realtek.com --- v2: - update comment and title. --- drivers/net/ethernet/realtek/r8169_main.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c index 62cabeeb842a..bb787a52bc75 100644 --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -196,6 +196,7 @@ enum rtl_registers { /* No threshold before first PCI xfer */ #define RX_FIFO_THRESH (7 << RXCFG_FIFO_SHIFT) #define RX_EARLY_OFF (1 << 11) +#define RX_PAUSE_SLOT_ON (1 << 11) /* 8125b and later */ #define RXCFG_DMA_SHIFT 8 /* Unlimited maximum PCI burst. */ #define RX_DMA_BURST (7 << RXCFG_DMA_SHIFT) @@ -2306,9 +2307,13 @@ static void rtl_init_rxcfg(struct rtl8169_private *tp) case RTL_GIGA_MAC_VER_40 ... RTL_GIGA_MAC_VER_53: RTL_W32(tp, RxConfig, RX128_INT_EN | RX_MULTI_EN | RX_DMA_BURST | RX_EARLY_OFF); break; - case RTL_GIGA_MAC_VER_61 ... RTL_GIGA_MAC_VER_63: + case RTL_GIGA_MAC_VER_61: RTL_W32(tp, RxConfig, RX_FETCH_DFLT_8125 | RX_DMA_BURST); break; + case RTL_GIGA_MAC_VER_63: + RTL_W32(tp, RxConfig, RX_FETCH_DFLT_8125 | RX_DMA_BURST | + RX_PAUSE_SLOT_ON); + break; default: RTL_W32(tp, RxConfig, RX128_INT_EN | RX_DMA_BURST); break;