[PATCH 5.10 110/142] ice: Dont allow more channels than LAN MSI-X available

Greg Kroah-Hartman
2021-02-02T19:38:01Z

From: Brett Creeley <brett.creeley@intel.com>

[ Upstream commit 943b881e35829403da638fcb34a959125deafef3 ]

Currently users could create more channels than LAN MSI-X available.
This is happening because there is no check against pf->num_lan_msix
when checking the max allowed channels and will cause performance issues
if multiple Tx and Rx queues are tied to a single MSI-X. Fix this by not
allowing more channels than LAN MSI-X available in pf->num_lan_msix.

Fixes: 87324e747fde ("ice: Implement ethtool ops for channels")
Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/intel/ice/ice_ethtool.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index 9e8e9531cd871..69c113a4de7e6 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -3258,8 +3258,8 @@ ice_set_rxfh(struct net_device *netdev, const u32 *indir, const u8 *key,
*/
static int ice_get_max_txq(struct ice_pf *pf)
{
- return min_t(int, num_online_cpus(),
- pf->hw.func_caps.common_cap.num_txq);
+ return min3(pf->num_lan_msix, (u16)num_online_cpus(),
+ (u16)pf->hw.func_caps.common_cap.num_txq);
}

/**
@@ -3268,8 +3268,8 @@ static int ice_get_max_txq(struct ice_pf *pf)
*/
static int ice_get_max_rxq(struct ice_pf *pf)
{
- return min_t(int, num_online_cpus(),
- pf->hw.func_caps.common_cap.num_rxq);
+ return min3(pf->num_lan_msix, (u16)num_online_cpus(),
+ (u16)pf->hw.func_caps.common_cap.num_rxq);
}

/**
--
2.27.0