On Tue, Feb 23, 2021 at 09:01:06AM -0800, Jakub Kicinski wrote:
> On Tue, 23 Feb 2021 14:24:40 +0100 Simon Horman wrote:
> > From: Yinjun Zhang <yinjun.zh...@corigine.com>
> >
> > The command "ethtool -L <intf> combined 0" may clean the RX/TX channel
> > count and skip the error path, since the attrs
> > tb[ETHTOOL_A_CHANNELS_RX_COUNT] and tb[ETHTOOL_A_CHANNELS_TX_COUNT]
> > are NULL in this case when recent ethtool is used.
> >
> > Tested using ethtool v5.10.
> >
> > Fixes: 7be92514b99c ("ethtool: check if there is at least one channel for
> > TX/RX in the core")
> > Signed-off-by: Yinjun Zhang <yinjun.zh...@corigine.com>
> > Signed-off-by: Simon Horman <simon.hor...@netronome.com>
> > Signed-off-by: Louis Peens <louis.pe...@netronome.com>
>
> Please make sure you CC Michal on ethtool patches.
>
> > diff --git a/net/ethtool/channels.c b/net/ethtool/channels.c
> > index 25a9e566ef5c..e35ef627f61f 100644
> > --- a/net/ethtool/channels.c
> > +++ b/net/ethtool/channels.c
> > @@ -175,14 +175,14 @@ int ethnl_set_channels(struct sk_buff *skb, struct
> > genl_info *info)
> >
> > /* ensure there is at least one RX and one TX channel */
> > if (!channels.combined_count && !channels.rx_count)
> > - err_attr = tb[ETHTOOL_A_CHANNELS_RX_COUNT];
> > + err_attr = mod_combined ? tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT]
> > :
> > + tb[ETHTOOL_A_CHANNELS_RX_COUNT];
> > else if (!channels.combined_count && !channels.tx_count)
> > - err_attr = tb[ETHTOOL_A_CHANNELS_TX_COUNT];
> > + err_attr = mod_combined ? tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT]
> > :
> > + tb[ETHTOOL_A_CHANNELS_TX_COUNT];
> > else
> > err_attr = NULL;
> > if (err_attr) {
> > - if (mod_combined)
> > - err_attr = tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT];
> > ret = -EINVAL;
> > NL_SET_ERR_MSG_ATTR(info->extack, err_attr, "requested channel
> > counts would result in no RX or TX channel being configured");
> > goto out_ops;
>
> In case driver decides to adjust max counts - I'd lean towards:
I missed this note while reading the e-mail for the first time so I
thouoght this was just a cleanup. You are right, this would address both
issues.
Michal
>
> diff --git a/net/ethtool/channels.c b/net/ethtool/channels.c
> index 5635604cb9ba..73d267415819 100644
> --- a/net/ethtool/channels.c
> +++ b/net/ethtool/channels.c
> @@ -116,10 +116,10 @@ int ethnl_set_channels(struct sk_buff *skb, struct
> genl_info *info)
> struct ethtool_channels channels = {};
> struct ethnl_req_info req_info = {};
> struct nlattr **tb = info->attrs;
> - const struct nlattr *err_attr;
> const struct ethtool_ops *ops;
> struct net_device *dev;
> u32 max_rx_in_use = 0;
> + u32 err_attr;
> int ret;
>
> ret = ethnl_parse_header_dev_get(&req_info,
> @@ -157,34 +157,34 @@ int ethnl_set_channels(struct sk_buff *skb, struct
> genl_info *info)
>
> /* ensure new channel counts are within limits */
> if (channels.rx_count > channels.max_rx)
> - err_attr = tb[ETHTOOL_A_CHANNELS_RX_COUNT];
> + err_attr = ETHTOOL_A_CHANNELS_RX_COUNT;
> else if (channels.tx_count > channels.max_tx)
> - err_attr = tb[ETHTOOL_A_CHANNELS_TX_COUNT];
> + err_attr = ETHTOOL_A_CHANNELS_TX_COUNT;
> else if (channels.other_count > channels.max_other)
> - err_attr = tb[ETHTOOL_A_CHANNELS_OTHER_COUNT];
> + err_attr = ETHTOOL_A_CHANNELS_OTHER_COUNT;
> else if (channels.combined_count > channels.max_combined)
> - err_attr = tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT];
> + err_attr = ETHTOOL_A_CHANNELS_COMBINED_COUNT;
> else
> - err_attr = NULL;
> + err_attr = 0;
> if (err_attr) {
> ret = -EINVAL;
> - NL_SET_ERR_MSG_ATTR(info->extack, err_attr,
> + NL_SET_ERR_MSG_ATTR(info->extack, tb[err_attr],
> "requested channel count exceeds
> maximum");
> goto out_ops;
> }
>
> /* ensure there is at least one RX and one TX channel */
> if (!channels.combined_count && !channels.rx_count)
> - err_attr = tb[ETHTOOL_A_CHANNELS_RX_COUNT];
> + err_attr = ETHTOOL_A_CHANNELS_RX_COUNT;
> else if (!channels.combined_count && !channels.tx_count)
> - err_attr = tb[ETHTOOL_A_CHANNELS_TX_COUNT];
> + err_attr = ETHTOOL_A_CHANNELS_TX_COUNT;
> else
> - err_attr = NULL;
> + err_attr = 0;
> if (err_attr) {
> if (mod_combined)
> - err_attr = tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT];
> + err_attr = ETHTOOL_A_CHANNELS_COMBINED_COUNT;
> ret = -EINVAL;
> - NL_SET_ERR_MSG_ATTR(info->extack, err_attr, "requested
> channel counts would result in no RX or TX channel being configured");
> + NL_SET_ERR_MSG_ATTR(info->extack, tb[err_attr], "requested
> channel counts would result in no RX or TX channel being configured");
> goto out_ops;
> }
>
