On Sun, Mar 30, 2014 at 09:08:06PM +0300, Or Gerlitz wrote:

On Sun, Mar 30, 2014 at 6:26 PM, Amir Vadai [off-list ref] wrote:

quoted

Fix issue introduced by commit: 97a5221 "net/mlx4_core: pass
pci_device_id.driver_data to __mlx4_init_one during reset".

pci_match_id() might return NULL if someone binds the driver to a device
manually using /sys/bus/pci/drivers/.../new_id. Need to check 'id'
before using it.

Thanks to Bjorn who raised the problem.

Well, that commit was applied to net and is now present in Linus
tree... so assuming it's too late for 3.14, need to queue this for
-stable

Or.

Sorry for this bothering, hope this will not block someone.

Here is my suggestion for fixing this, not sure this is a good way to export
pci_match_device() to modules. This is my current solution to this problem. If
you have any comments, please let me know.

------------------------------------------------------------------------------

From 9361e1edd6776202c6e11dd44d3d4d72c990b111 Mon Sep 17 00:00:00 2001

From: Wei Yang <redacted>
Date: Mon, 31 Mar 2014 11:34:57 +0800
Subject: [PATCH net-next] net/mlx4_core: match pci_device_id including dynids

Fix issue introduced by commit: 97a5221 "net/mlx4_core: pass
pci_device_id.driver_data to __mlx4_init_one during reset".

pci_match_id() just match the static pci_device_id, which may return NULL if
someone binds the driver to a device manually using
/sys/bus/pci/drivers/.../new_id.

This patch match pci_device_id with pci_match_device() to cover both dynids
and static id_table.

Thanks to Bjorn finding this issue.

CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Amir Vadai <redacted>
Signed-off-by: Wei Yang <redacted>
---
 drivers/net/ethernet/mellanox/mlx4/main.c |    4 +++-
 drivers/pci/pci-driver.c                  |    3 ++-
 include/linux/pci.h                       |    2 ++
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index aa54ef7..b0edb5c 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c

@@ -2673,7 +2673,9 @@ static pci_ers_result_t mlx4_pci_slot_reset(struct pci_dev *pdev)
 	const struct pci_device_id *id;
 	int ret;
 
-	id = pci_match_id(mlx4_pci_table, pdev);
+	id = pci_match_device(pci_dev_driver(pdev), pdev);
+	BUG_ON(!id);
+
 	ret = __mlx4_init_one(pdev, id->driver_data);
 
 	return ret ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 25f0bc6..1ee26a1 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c

@@ -225,7 +225,7 @@ const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
  * system is in its list of supported devices.  Returns the matching
  * pci_device_id structure or %NULL if there is no match.
  */
-static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
+const struct pci_device_id *pci_match_device(struct pci_driver *drv,
 						    struct pci_dev *dev)
 {
 	struct pci_dynid *dynid;

@@ -1355,6 +1355,7 @@ postcore_initcall(pci_driver_init);
 
 EXPORT_SYMBOL_GPL(pci_add_dynid);
 EXPORT_SYMBOL(pci_match_id);
+EXPORT_SYMBOL(pci_match_device);
 EXPORT_SYMBOL(__pci_register_driver);
 EXPORT_SYMBOL(pci_unregister_driver);
 EXPORT_SYMBOL(pci_dev_driver);

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 6d1cc9e..d7a7d05 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h

@@ -1135,6 +1135,8 @@ int pci_add_dynid(struct pci_driver *drv,
 		  unsigned long driver_data);
 const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
 					 struct pci_dev *dev);
+const struct pci_device_id *pci_match_device(struct pci_driver *drv,
+						    struct pci_dev *dev);
 int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 		    int pass);
 

-- 
1.7.9.5


-- 
Richard Yang
Help you, Help me