diff mbox

[1/2] igb: fix rtnl race in PM resume path

Message ID 1333638664-17062-1-git-send-email-bpoirier@suse.de
State Awaiting Upstream, archived
Delegated to: David Miller
Headers show

Commit Message

Benjamin Poirier April 5, 2012, 3:11 p.m. UTC 
Since the caller (PM resume code) is not the one holding rtnl, when taking the
'else' branch rtnl may be released at any moment, thereby defeating the whole
purpose of this code block.

Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
---
 drivers/net/ethernet/intel/igb/igb_main.c |   20 ++++++--------------
 1 files changed, 6 insertions(+), 14 deletions(-)

Comments

Kirsher, Jeffrey T April 5, 2012, 11:02 p.m. UTC | #1 
On Thu, 2012-04-05 at 11:11 -0400, Benjamin Poirier wrote:
> Since the caller (PM resume code) is not the one holding rtnl, when
> taking the
> 'else' branch rtnl may be released at any moment, thereby defeating
> the whole
> purpose of this code block.
> 
> Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
> ---
>  drivers/net/ethernet/intel/igb/igb_main.c |   20 ++++++--------------
>  1 files changed, 6 insertions(+), 14 deletions(-) 

Thanks Benjamin, I will add the patch to my igb queue of patches.
diff mbox

Patch

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index f022ff7..4854ab6 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -1083,9 +1083,12 @@  msi_only:
 		adapter->flags |= IGB_FLAG_HAS_MSI;
 out:
 	/* Notify the stack of the (possibly) reduced queue counts. */
+	rtnl_lock();
 	netif_set_real_num_tx_queues(adapter->netdev, adapter->num_tx_queues);
-	return netif_set_real_num_rx_queues(adapter->netdev,
-					    adapter->num_rx_queues);
+	err = netif_set_real_num_rx_queues(adapter->netdev,
+		adapter->num_rx_queues);
+	rtnl_unlock();
+	return err;
 }
 
 /**
@@ -6646,18 +6649,7 @@  static int igb_resume(struct device *dev)
 	pci_enable_wake(pdev, PCI_D3hot, 0);
 	pci_enable_wake(pdev, PCI_D3cold, 0);
 
-	if (!rtnl_is_locked()) {
-		/*
-		 * shut up ASSERT_RTNL() warning in
-		 * netif_set_real_num_tx/rx_queues.
-		 */
-		rtnl_lock();
-		err = igb_init_interrupt_scheme(adapter);
-		rtnl_unlock();
-	} else {
-		err = igb_init_interrupt_scheme(adapter);
-	}
-	if (err) {
+	if (igb_init_interrupt_scheme(adapter)) {
 		dev_err(&pdev->dev, "Unable to allocate memory for queues\n");
 		return -ENOMEM;
 	}