From 8f76e549e9c52366c48169f18c80c2e0557a0791 Mon Sep 17 00:00:00 2001 From: Brian King Date: Fri, 17 Nov 2017 11:05:49 -0600 Subject: [PATCH] i40evf: Use smp_rmb rather than read_barrier_depends commit f72271e2a0ae4277d53c4053f5eed8bb346ba38a upstream. The original issue being fixed in this patch was seen with the ixgbe driver, but the same issue exists with i40evf as well, as the code is very similar. read_barrier_depends is not sufficient to ensure loads following it are not speculatively loaded out of order by the CPU, which can result in stale data being loaded, causing potential system crashes. Signed-off-by: Brian King Acked-by: Jesse Brandeburg Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c index 75f2a2cdd738..c03800d1000a 100644 --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -184,7 +184,7 @@ static bool i40e_clean_tx_irq(struct i40e_vsi *vsi, break; /* prevent any other reads prior to eop_desc */ - read_barrier_depends(); + smp_rmb(); /* we have caught up to head, no work left to do */ if (tx_head == tx_desc) -- 2.34.1