From c6210760f2428690255e1fd91cf084b12e827a0a Mon Sep 17 00:00:00 2001 From: Dmitry Fleytman Date: Tue, 13 Oct 2015 12:48:18 +0300 Subject: [PATCH] e1000e: fix division by zero on jumbo MTUs [ Upstream commit b77ac46bbae862dcb3f51296825c940404c69b0f ] This patch fixes possible division by zero in receive interrupt handler when working without adaptive interrupt moderation. The adaptive interrupt moderation mechanism is typically disabled on jumbo MTUs. Signed-off-by: Dmitry Fleytman Signed-off-by: Leonid Bloch Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/intel/e1000e/netdev.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 0a854a47d31a..80ec587d510e 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -1959,8 +1959,10 @@ static irqreturn_t e1000_intr_msix_rx(int __always_unused irq, void *data) * previous interrupt. */ if (rx_ring->set_itr) { - writel(1000000000 / (rx_ring->itr_val * 256), - rx_ring->itr_register); + u32 itr = rx_ring->itr_val ? + 1000000000 / (rx_ring->itr_val * 256) : 0; + + writel(itr, rx_ring->itr_register); rx_ring->set_itr = 0; } -- 2.34.1