From 0e4248a114bb1735078c2ef2e954e847aa67cdb9 Mon Sep 17 00:00:00 2001
From: Hans Petter Selasky <hselasky@FreeBSD.org>
Date: Fri, 10 Nov 2017 13:40:27 +0000
Subject: [PATCH] Prevent mlx5 core from accessing host memory after shutdown
 by disabling PCI busmaster.

Sponsored by:	Mellanox Technologies
MFC after:	1 week
---
 sys/dev/mlx5/mlx5_core/mlx5_main.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/sys/dev/mlx5/mlx5_core/mlx5_main.c b/sys/dev/mlx5/mlx5_core/mlx5_main.c
index 5c102f40ea2..07a04b232d0 100644
--- a/sys/dev/mlx5/mlx5_core/mlx5_main.c
+++ b/sys/dev/mlx5/mlx5_core/mlx5_main.c
@@ -1134,6 +1134,12 @@ static void remove_one(struct pci_dev *pdev)
 	kfree(dev);
 }
 
+static void shutdown_one(struct pci_dev *pdev)
+{
+	/* prevent device from accessing host memory after shutdown */
+	pci_clear_master(pdev);
+}
+
 static const struct pci_device_id mlx5_core_pci_table[] = {
 	{ PCI_VDEVICE(MELLANOX, 4113) }, /* Connect-IB */
 	{ PCI_VDEVICE(MELLANOX, 4114) }, /* Connect-IB VF */
@@ -1175,6 +1181,7 @@ MODULE_DEVICE_TABLE(pci, mlx5_core_pci_table);
 static struct pci_driver mlx5_core_driver = {
 	.name           = DRIVER_NAME,
 	.id_table       = mlx5_core_pci_table,
+	.shutdown	= shutdown_one,
 	.probe          = init_one,
 	.remove         = remove_one
 };