On Tue, 20 Jan 2026 18:34:40 +0900, Takashi Kozu wrote:
> Change igc_set_rxfh() to accept and save a userspace-provided
> RSS key. When a key is provided, store it in the adapter and write the
> E1000 registers accordingly.
>
> This can be tested using `ethtool -X <dev> hkey <key>`.
>
> Signed-off-by: Takashi Kozu <[email protected]>
> ---
> drivers/net/ethernet/intel/igb/igb.h | 1 +
> drivers/net/ethernet/intel/igb/igb_ethtool.c | 49 +++++++++++---------
> drivers/net/ethernet/intel/igb/igb_main.c | 3 +-
> 3 files changed, 30 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/igb/igb.h
> b/drivers/net/ethernet/intel/igb/igb.h
> index 8c9b02058cec..2509ec30acf3 100644
> --- a/drivers/net/ethernet/intel/igb/igb.h
> +++ b/drivers/net/ethernet/intel/igb/igb.h
> @@ -657,6 +657,7 @@ struct igb_adapter {
> u32 rss_indir_tbl_init;
> u8 rss_indir_tbl[IGB_RETA_SIZE];
> u8 rss_key[IGB_RSS_KEY_SIZE];
> + bool has_user_rss_key;
Hi Kozu-san.
While preparing for testing, I noticed that now 'has_user_rss_key' is
not necessary.
Since netdev_rss_key_fill() is called in igb_sw_init() and igb_sw_init()
is called only once for the adapter's lifetime, adapter->rss_key
wouldn't be changed except for user-intended change.
I'd drop that flag and related code (see below)
>
> unsigned long link_check_timeout;
> int copper_tries;
> diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c
> b/drivers/net/ethernet/intel/igb/igb_ethtool.c
> index b387121f0ea7..1db9c2447c91 100644
> --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
> +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
> @@ -3357,35 +3357,40 @@ static int igb_set_rxfh(struct net_device *netdev,
> u32 num_queues;
>
> /* We do not allow change in unsupported parameters */
> - if (rxfh->key ||
> - (rxfh->hfunc != ETH_RSS_HASH_NO_CHANGE &&
> - rxfh->hfunc != ETH_RSS_HASH_TOP))
> + if (rxfh->hfunc != ETH_RSS_HASH_NO_CHANGE &&
> + rxfh->hfunc != ETH_RSS_HASH_TOP)
> return -EOPNOTSUPP;
> - if (!rxfh->indir)
> - return 0;
>
> - num_queues = adapter->rss_queues;
> + if (rxfh->indir) {
> + num_queues = adapter->rss_queues;
>
> - switch (hw->mac.type) {
> - case e1000_82576:
> - /* 82576 supports 2 RSS queues for SR-IOV */
> - if (adapter->vfs_allocated_count)
> - num_queues = 2;
> - break;
> - default:
> - break;
> - }
> + switch (hw->mac.type) {
> + case e1000_82576:
> + /* 82576 supports 2 RSS queues for SR-IOV */
> + if (adapter->vfs_allocated_count)
> + num_queues = 2;
> + break;
> + default:
> + break;
> + }
>
> - /* Verify user input. */
> - for (i = 0; i < IGB_RETA_SIZE; i++)
> - if (rxfh->indir[i] >= num_queues)
> - return -EINVAL;
> + /* Verify user input. */
> + for (i = 0; i < IGB_RETA_SIZE; i++)
> + if (rxfh->indir[i] >= num_queues)
> + return -EINVAL;
>
>
> - for (i = 0; i < IGB_RETA_SIZE; i++)
> - adapter->rss_indir_tbl[i] = rxfh->indir[i];
> + for (i = 0; i < IGB_RETA_SIZE; i++)
> + adapter->rss_indir_tbl[i] = rxfh->indir[i];
> +
> + igb_write_rss_indir_tbl(adapter);
> + }
>
> - igb_write_rss_indir_tbl(adapter);
> + if (rxfh->key) {
> + adapter->has_user_rss_key = true;
here
> + memcpy(adapter->rss_key, rxfh->key, sizeof(adapter->rss_key));
> + igb_write_rss_key(adapter);
> + }
>
> return 0;
> }
> diff --git a/drivers/net/ethernet/intel/igb/igb_main.c
> b/drivers/net/ethernet/intel/igb/igb_main.c
> index c703011b19ec..8dab133296ca 100644
> --- a/drivers/net/ethernet/intel/igb/igb_main.c
> +++ b/drivers/net/ethernet/intel/igb/igb_main.c
> @@ -4051,7 +4051,8 @@ static int igb_sw_init(struct igb_adapter *adapter)
> pci_read_config_word(pdev, PCI_COMMAND, &hw->bus.pci_cmd_word);
>
> /* init RSS key */
> - netdev_rss_key_fill(adapter->rss_key, sizeof(adapter->rss_key));
> + if (!adapter->has_user_rss_key)
> + netdev_rss_key_fill(adapter->rss_key, sizeof(adapter->rss_key));
and this diff.
>
> /* set default ring sizes */
> adapter->tx_ring_count = IGB_DEFAULT_TXD;
> --
> 2.52.0
