6.6-stable review patch. If anyone has any objections, please let me know.
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From: Larysa Zaremba larysa.zaremba@intel.com
[ Upstream commit 05d6f442f31f901d27dbc64fd504a8ec7d5013de ]
A bug occurs because a safety check guarding AF_XDP-related queues in ethnl_set_channels(), does not trigger. This happens, because kernel and ice driver interpret the ethtool command differently.
How the bug occurs: 1. ethtool -l <IFNAME> -> combined: 40 2. Attach AF_XDP to queue 30 3. ethtool -L <IFNAME> rx 15 tx 15 combined number is not specified, so command becomes {rx_count = 15, tx_count = 15, combined_count = 40}. 4. ethnl_set_channels checks, if there are any AF_XDP of queues from the new (combined_count + rx_count) to the old one, so from 55 to 40, check does not trigger. 5. ice interprets `rx 15 tx 15` as 15 combined channels and deletes the queue that AF_XDP is attached to.
Interpret the command in a way that is more consistent with ethtool manual [0] (--show-channels and --set-channels).
Considering that in the ice driver only the difference between RX and TX queues forms dedicated channels, change the correct way to set number of channels to:
ethtool -L <IFNAME> combined 10 /* For symmetric queues */ ethtool -L <IFNAME> combined 8 tx 2 rx 0 /* For asymmetric queues */
[0] https://man7.org/linux/man-pages/man8/ethtool.8.html
Fixes: 87324e747fde ("ice: Implement ethtool ops for channels") Reviewed-by: Michal Swiatkowski michal.swiatkowski@linux.intel.com Signed-off-by: Larysa Zaremba larysa.zaremba@intel.com Tested-by: Chandan Kumar Rout chandanx.rout@intel.com Tested-by: Pucha Himasekhar Reddy himasekharx.reddy.pucha@intel.com Acked-by: Maciej Fijalkowski maciej.fijalkowski@intel.com Signed-off-by: Jacob Keller jacob.e.keller@intel.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/ice/ice_ethtool.c | 19 ++----------------- 1 file changed, 2 insertions(+), 17 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c index 9be13e9840917..39b5f24be7e4f 100644 --- a/drivers/net/ethernet/intel/ice/ice_ethtool.c +++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c @@ -3429,7 +3429,6 @@ static int ice_set_channels(struct net_device *dev, struct ethtool_channels *ch) struct ice_pf *pf = vsi->back; int new_rx = 0, new_tx = 0; bool locked = false; - u32 curr_combined; int ret = 0;
/* do not support changing channels in Safe Mode */ @@ -3451,22 +3450,8 @@ static int ice_set_channels(struct net_device *dev, struct ethtool_channels *ch) return -EOPNOTSUPP; }
- curr_combined = ice_get_combined_cnt(vsi); - - /* these checks are for cases where user didn't specify a particular - * value on cmd line but we get non-zero value anyway via - * get_channels(); look at ethtool.c in ethtool repository (the user - * space part), particularly, do_schannels() routine - */ - if (ch->rx_count == vsi->num_rxq - curr_combined) - ch->rx_count = 0; - if (ch->tx_count == vsi->num_txq - curr_combined) - ch->tx_count = 0; - if (ch->combined_count == curr_combined) - ch->combined_count = 0; - - if (!(ch->combined_count || (ch->rx_count && ch->tx_count))) { - netdev_err(dev, "Please specify at least 1 Rx and 1 Tx channel\n"); + if (ch->rx_count && ch->tx_count) { + netdev_err(dev, "Dedicated RX or TX channels cannot be used simultaneously\n"); return -EINVAL; }