[dpdk-stable] [PATCH] ethdev: fix secondary process change share memory

[Fang TongHao <fangtonghao@sangfor.com.cn>]

Hi all，I am from Sangfor Tech.I found a bug when using DPDK in
multiprocess scenario.The secondary process enters
"rte_eth_dev_pci_copy_info" function when initializing.Then it
sets the value of struct "rte_eth_dev_data.dev_flags" to zero,
but this struct is shared by primary process and secondary
process, and the value change is unexpected by primary process.
This may cause very serious damage.I think
the secondary process should not enter "rte_eth_dev_pci_copy_info"
function or changes the value of struct "rte_eth_dev_data.dev_flags"
in shared memory.
I fixed this bug by adding an if-statement to forbid the secondary
process changing the above-mentioned value.
Thansk, All.
Cc: stable@dpdk.org

Signed-off-by: Fang TongHao <fangtonghao@sangfor.com.cn>
---
 lib/librte_ethdev/rte_ethdev_pci.h | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/lib/librte_ethdev/rte_ethdev_pci.h b/lib/librte_ethdev/rte_ethdev_pci.h
index ccdbb46ec..916de8a14 100644
--- a/lib/librte_ethdev/rte_ethdev_pci.h
+++ b/lib/librte_ethdev/rte_ethdev_pci.h
@@ -59,15 +59,16 @@ rte_eth_copy_pci_info(struct rte_eth_dev *eth_dev,
 	}
 
 	eth_dev->intr_handle = &pci_dev->intr_handle;
-
-	eth_dev->data->dev_flags = 0;
-	if (pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_LSC)
-		eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_LSC;
-	if (pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_RMV)
-		eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_RMV;
-
-	eth_dev->data->kdrv = pci_dev->kdrv;
-	eth_dev->data->numa_node = pci_dev->device.numa_node;
+	if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
+		eth_dev->data->dev_flags = 0;
+		if (pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_LSC)
+			eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_LSC;
+		if (pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_RMV)
+			eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_RMV;
+
+		eth_dev->data->kdrv = pci_dev->kdrv;
+		eth_dev->data->numa_node = pci_dev->device.numa_node;
+	}
 }
 
 static inline int
-- 
2.24.1.windows.2