> -----Original Message----- > From: Intel-wired-lan <[email protected]> On Behalf Of > Larysa Zaremba > Sent: Thursday, April 18, 2024 3:29 PM > To: Nguyen, Anthony L <[email protected]>; > [email protected]; [email protected]; > [email protected] > Cc: Fijalkowski, Maciej <[email protected]>; Tantilov, Emil S > <[email protected]>; Zaremba, Larysa <[email protected]>; > Czapnik, Lukasz <[email protected]>; Eric Dumazet > <[email protected]>; Brady, Alan <[email protected]>; Michal Swiatkowski > <[email protected]>; Jakub Kicinski <[email protected]>; Paolo > Abeni <[email protected]>; David S. Miller <[email protected]> > Subject: [Intel-wired-lan] [PATCH RESEND iwl-net] ice: Interpret > .set_channels() input differently > > 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 <[email protected]> > Signed-off-by: Larysa Zaremba <[email protected]> > --- > drivers/net/ethernet/intel/ice/ice_ethtool.c | 22 ++++++-------------- > 1 file changed, 6 insertions(+), 16 deletions(-) >
Tested-by: Pucha Himasekhar Reddy <[email protected]> (A Contingent worker at Intel)
