| Message ID | 20240418095857.2827-1-larysa.zaremba@intel.com |
|---|---|
| State | Accepted |
| Delegated to: | Anthony Nguyen |
| Headers | show |
| Series | [RESEND,iwl-net] ice: Interpret .set_channels() input differently | expand |
>-----Original Message----- >From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of >Zaremba, Larysa >Sent: Thursday, April 18, 2024 3:29 PM >To: Nguyen, Anthony L <anthony.l.nguyen@intel.com>; intel-wired- >lan@lists.osuosl.org; linux-kernel@vger.kernel.org; netdev@vger.kernel.org >Cc: Fijalkowski, Maciej <maciej.fijalkowski@intel.com>; Tantilov, Emil S ><emil.s.tantilov@intel.com>; Zaremba, Larysa <larysa.zaremba@intel.com>; >Czapnik, Lukasz <lukasz.czapnik@intel.com>; Eric Dumazet ><edumazet@google.com>; Brady, Alan <alan.brady@intel.com>; Michal >Swiatkowski <michal.swiatkowski@linux.intel.com>; Jakub Kicinski ><kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; David S. Miller ><davem@davemloft.net> >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 <michal.swiatkowski@linux.intel.com> >Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com> >--- > drivers/net/ethernet/intel/ice/ice_ethtool.c | 22 ++++++-------------- > 1 file changed, 6 insertions(+), 16 deletions(-) > Tested-by: Chandan Kumar Rout <chandanx.rout@intel.com> (A Contingent Worker at Intel)
> -----Original Message----- > From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of Larysa Zaremba > Sent: Thursday, April 18, 2024 3:29 PM > To: Nguyen, Anthony L <anthony.l.nguyen@intel.com>; intel-wired-lan@lists.osuosl.org; linux-kernel@vger.kernel.org; netdev@vger.kernel.org > Cc: Fijalkowski, Maciej <maciej.fijalkowski@intel.com>; Tantilov, Emil S <emil.s.tantilov@intel.com>; Zaremba, Larysa <larysa.zaremba@intel.com>; Czapnik, Lukasz <lukasz.czapnik@intel.com>; Eric Dumazet <edumazet@google.com>; Brady, Alan <alan.brady@intel.com>; Michal Swiatkowski <michal.swiatkowski@linux.intel.com>; Jakub Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; David S. Miller <davem@davemloft.net> > 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 <michal.swiatkowski@linux.intel.com> > Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com> > --- > drivers/net/ethernet/intel/ice/ice_ethtool.c | 22 ++++++-------------- > 1 file changed, 6 insertions(+), 16 deletions(-) > Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c index 78b833b3e1d7..d91f41f61bce 100644 --- a/drivers/net/ethernet/intel/ice/ice_ethtool.c +++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c @@ -3593,7 +3593,6 @@ 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 */ @@ -3615,22 +3614,13 @@ static int ice_set_channels(struct net_device *dev, struct ethtool_channels *ch) return -EOPNOTSUPP; } - curr_combined = ice_get_combined_cnt(vsi); + if (!ch->combined_count) { + netdev_err(dev, "Please specify at least 1 combined channel\n"); + return -EINVAL; + } - /* 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; }
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> --- drivers/net/ethernet/intel/ice/ice_ethtool.c | 22 ++++++-------------- 1 file changed, 6 insertions(+), 16 deletions(-)