[dpdk-dev] [PATCH v2 1/2] bus/pci: fix find device implementation

[Gaetan Rivet <gaetan.rivet@6wind.com>]

If start is set, and a device before it matches the data
passed for comparison, then this first device is returned.

This induces potentially infinite loops.

Fixes: c7fe1eea8a74 ("bus: simplify finding starting point")
Cc: stable@dpdk.org

Signed-off-by: Gaetan Rivet <gaetan.rivet@6wind.com>
---
 drivers/bus/pci/pci_common.c  | 21 ++++++++++++---------
 drivers/bus/pci/rte_bus_pci.h |  3 +++
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/drivers/bus/pci/pci_common.c b/drivers/bus/pci/pci_common.c
index 6bed0bc9d..7215aaec3 100644
--- a/drivers/bus/pci/pci_common.c
+++ b/drivers/bus/pci/pci_common.c
@@ -455,17 +455,20 @@ static struct rte_device *
 pci_find_device(const struct rte_device *start, rte_dev_cmp_t cmp,
 		const void *data)
 {
-	struct rte_pci_device *dev;
+	const struct rte_pci_device *pstart;
+	struct rte_pci_device *pdev;
 
-	FOREACH_DEVICE_ON_PCIBUS(dev) {
-		if (start && &dev->device == start) {
-			start = NULL; /* starting point found */
-			continue;
-		}
-		if (cmp(&dev->device, data) == 0)
-			return &dev->device;
+	if (start != NULL) {
+		pstart = RTE_DEV_TO_PCI_CONST(start);
+		pdev = TAILQ_NEXT(pstart, next);
+	} else {
+		pdev = TAILQ_FIRST(&rte_pci_bus.device_list);
+	}
+	while (pdev != NULL) {
+		if (cmp(&pdev->device, data) == 0)
+			return &pdev->device;
+		pdev = TAILQ_NEXT(pdev, next);
 	}
-
 	return NULL;
 }
 
diff --git a/drivers/bus/pci/rte_bus_pci.h b/drivers/bus/pci/rte_bus_pci.h
index 357afb912..458e6d076 100644
--- a/drivers/bus/pci/rte_bus_pci.h
+++ b/drivers/bus/pci/rte_bus_pci.h
@@ -74,6 +74,9 @@ struct rte_pci_device {
  */
 #define RTE_DEV_TO_PCI(ptr) container_of(ptr, struct rte_pci_device, device)
 
+#define RTE_DEV_TO_PCI_CONST(ptr) \
+	container_of(ptr, const struct rte_pci_device, device)
+
 #define RTE_ETH_DEV_TO_PCI(eth_dev)	RTE_DEV_TO_PCI((eth_dev)->device)
 
 /** Any PCI device identifier (vendor, device, ...) */
-- 
2.11.0