diff mbox series

[S13,v2,04/17] ice: fix the divide by zero issue

Message ID 20190227003523.28733-5-anirudh.venkataramanan@intel.com
State Accepted
Delegated to: Jeff Kirsher
Headers show
Series Bug fixes and minor feature updates for ice | expand

Commit Message

Anirudh Venkataramanan Feb. 27, 2019, 12:35 a.m. UTC 
From: Kiran Patil <kiran.patil@intel.com>

Static analysis flagged a potential divide by zero error because
vsi->num_rxq can become zero in certain condition and it is used as
divisor.

Signed-off-by: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
---
[Anirudh Venkataramanan <anirudh.venkataramanan@intel.com> cleaned up commit message]
---
 drivers/net/ethernet/intel/ice/ice_lib.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

Comments

Bowers, AndrewX Feb. 28, 2019, 11:08 p.m. UTC | #1 
> -----Original Message-----
> From: Intel-wired-lan [mailto:intel-wired-lan-bounces@osuosl.org] On
> Behalf Of Anirudh Venkataramanan
> Sent: Tuesday, February 26, 2019 4:35 PM
> To: intel-wired-lan@lists.osuosl.org
> Subject: [Intel-wired-lan] [PATCH S13 v2 04/17] ice: fix the divide by zero
> issue
> 
> From: Kiran Patil <kiran.patil@intel.com>
> 
> Static analysis flagged a potential divide by zero error because
> vsi->num_rxq can become zero in certain condition and it is used as
> divisor.
> 
> Signed-off-by: Kiran Patil <kiran.patil@intel.com>
> Signed-off-by: Anirudh Venkataramanan
> <anirudh.venkataramanan@intel.com>
> ---
> [Anirudh Venkataramanan <anirudh.venkataramanan@intel.com> cleaned
> up commit message]
> ---
>  drivers/net/ethernet/intel/ice/ice_lib.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)

Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index a602bd329cfa..5d364b79eb4d 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -881,7 +881,18 @@  static void ice_vsi_setup_q_map(struct ice_vsi *vsi, struct ice_vsi_ctx *ctxt)
 		tx_count += tx_numq_tc;
 		ctxt->info.tc_mapping[i] = cpu_to_le16(qmap);
 	}
-	vsi->num_rxq = offset;
+
+	/* if offset is non-zero, means it is calculated correctly based on
+	 * enabled TCs for a given VSI otherwise qcount_rx will always
+	 * be correct and non-zero because it is based off - VSI's
+	 * allocated Rx queues which is at least 1 (hence qcount_tx will be
+	 * at least 1)
+	 */
+	if (offset)
+		vsi->num_rxq = offset;
+	else
+		vsi->num_rxq = qcount_rx;
+
 	vsi->num_txq = tx_count;
 
 	if (vsi->type == ICE_VSI_VF && vsi->num_txq != vsi->num_rxq) {