This is a note to let you know that I've just added the patch titled

igbvf: Use smp_rmb rather than read_barrier_depends

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: igbvf-use-smp_rmb-rather-than-read_barrier_depends.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 1e1f9ca546556e508d021545861f6b5fc75a95fe Mon Sep 17 00:00:00 2001

From: Brian King brking@linux.vnet.ibm.com Date: Fri, 17 Nov 2017 11:05:46 -0600 Subject: igbvf: Use smp_rmb rather than read_barrier_depends

From: Brian King brking@linux.vnet.ibm.com

commit 1e1f9ca546556e508d021545861f6b5fc75a95fe upstream.

The original issue being fixed in this patch was seen with the ixgbe driver, but the same issue exists with igbvf 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 brking@linux.vnet.ibm.com Acked-by: Jesse Brandeburg jesse.brandeburg@intel.com Tested-by: Aaron Brown aaron.f.brown@intel.com Signed-off-by: Jeff Kirsher jeffrey.t.kirsher@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/net/ethernet/intel/igbvf/netdev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/intel/igbvf/netdev.c +++ b/drivers/net/ethernet/intel/igbvf/netdev.c @@ -810,7 +810,7 @@ static bool igbvf_clean_tx_irq(struct ig 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(E1000_TXD_STAT_DD)))

Patches currently in stable-queue which might be from brking@linux.vnet.ibm.com are

queue-4.9/i40evf-use-smp_rmb-rather-than-read_barrier_depends.patch queue-4.9/igb-use-smp_rmb-rather-than-read_barrier_depends.patch queue-4.9/ixgbevf-use-smp_rmb-rather-than-read_barrier_depends.patch queue-4.9/igbvf-use-smp_rmb-rather-than-read_barrier_depends.patch queue-4.9/fm10k-use-smp_rmb-rather-than-read_barrier_depends.patch queue-4.9/ixgbe-fix-skb-list-corruption-on-power-systems.patch queue-4.9/i40e-use-smp_rmb-rather-than-read_barrier_depends.patch