From: Brian King Date: Fri, 17 Nov 2017 17:05:45 +0000 (-0600) Subject: ixgbevf: Use smp_rmb rather than read_barrier_depends X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=a8e699dfca04191e209a63d484e347aa921422e2;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git ixgbevf: Use smp_rmb rather than read_barrier_depends commit ae0c585d93dfaf923d2c7eb44b2c3ab92854ea9b upstream. The original issue being fixed in this patch was seen with the ixgbe driver, but the same issue exists with ixgbevf 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 --- diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c index 592ff237d692..50bbad37d640 100644 --- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c +++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c @@ -312,7 +312,7 @@ static bool ixgbevf_clean_tx_irq(struct ixgbevf_q_vector *q_vector, break; /* prevent any other reads prior to eop_desc */ - read_barrier_depends(); + smp_rmb(); /* if DD is not set pending work has not been completed */ if (!(eop_desc->wb.status & cpu_to_le32(IXGBE_TXD_STAT_DD)))