diff mbox series

[next,S95,06/12] i40e: fix condition of WARN_ONCE for stat strings

Message ID 20180820151233.14629-6-alice.michael@intel.com
State Accepted
Delegated to: Jeff Kirsher
Headers show
Series None | expand

Commit Message

Michael, Alice Aug. 20, 2018, 3:12 p.m. UTC 
From: Jacob Keller <jacob.e.keller@intel.com>

Commit 9b10df596bd4 ("i40e: use WARN_ONCE to replace the commented
BUG_ON size check") introduced a warning check to make sure
that the size of the stat strings was always the expected value. This
code accidentally inverted the check of the data pointer. Fix this so
that we accurately count the size of the stats we copied in.

This fixes an erroneous WARN kernel splat that occurs when requesting
ethtool statistics.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Bowers, AndrewX Aug. 21, 2018, 7:36 p.m. UTC | #1 
> -----Original Message-----
> From: Intel-wired-lan [mailto:intel-wired-lan-bounces@osuosl.org] On
> Behalf Of Alice Michael
> Sent: Monday, August 20, 2018 8:12 AM
> To: Michael, Alice <alice.michael@intel.com>; intel-wired-
> lan@lists.osuosl.org
> Subject: [Intel-wired-lan] [next PATCH S95 06/12] i40e: fix condition of
> WARN_ONCE for stat strings
> 
> From: Jacob Keller <jacob.e.keller@intel.com>
> 
> Commit 9b10df596bd4 ("i40e: use WARN_ONCE to replace the commented
> BUG_ON size check") introduced a warning check to make sure that the size
> of the stat strings was always the expected value. This code accidentally
> inverted the check of the data pointer. Fix this so that we accurately count
> the size of the stats we copied in.
> 
> This fixes an erroneous WARN kernel splat that occurs when requesting
> ethtool statistics.
> 
> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> ---
>  drivers/net/ethernet/intel/i40e/i40e_ethtool.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Mauro S. M. Rodrigues Aug. 24, 2018, 1:50 a.m. UTC | #2 
On Mon, Aug 20, 2018 at 08:12:27AM -0700, Alice Michael wrote:
> From: Jacob Keller <jacob.e.keller@intel.com>
> 
> Commit 9b10df596bd4 ("i40e: use WARN_ONCE to replace the commented
> BUG_ON size check") introduced a warning check to make sure
> that the size of the stat strings was always the expected value. This
> code accidentally inverted the check of the data pointer. Fix this so
> that we accurately count the size of the stats we copied in.
> 
> This fixes an erroneous WARN kernel splat that occurs when requesting
> ethtool statistics.
> 
> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> ---
>  drivers/net/ethernet/intel/i40e/i40e_ethtool.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
Tested-by: Mauro S. M. Rodrigues <maurosr@linux.vnet.ibm.com>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index ecc30524..3ef9069 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -1863,7 +1863,7 @@  static void i40e_get_stat_strings(struct net_device *netdev, u8 *data)
 	for (i = 0; i < I40E_MAX_USER_PRIORITY; i++)
 		i40e_add_stat_strings(&data, i40e_gstrings_pfc_stats, i);
 
-	WARN_ONCE(p - data != i40e_get_stats_count(netdev) * ETH_GSTRING_LEN,
+	WARN_ONCE(data - p != i40e_get_stats_count(netdev) * ETH_GSTRING_LEN,
 		  "stat strings count mismatch!");
 }