[PATCH v2 3/3] common/sfc_efx/base: fix reading advertised autoneg ability

[Stephen Hemminger]

On Wed, 12 Aug 2026 21:10:17 +0400
Ivan Malov <ivan.malov at arknetworks.am> wrote:

> The issue is that when the user disables auto-negotiation by removing
> the capability bit from the 'advertised mask' (set method) and then
> reads the resulting capabilities, which involves querying MCDI, the
> bit reappears in the mask irrespective of the user's intent.
> 
> Fix this by remembering the user's intent before any link-state queries.
> 
> Fixes: 2a5cf77e6de8 ("common/sfc_efx/base: provide PHY link get method on Medford4")
> Fixes: 06f569de6c06 ("common/sfc_efx/base: decode netport link state on probe path")
> Cc: stable at dpdk.org
> 
> Suggested-by: Andy Moreton <andy.moreton at amd.com>
> Signed-off-by: Ivan Malov <ivan.malov at arknetworks.am>
> Reviewed-by: Viacheslav Galaktionov <viacheslav.galaktionov at arknetworks.am>
> Reviewed-by: Andy Moreton <andy.moreton at amd.com>

This patch depends on the previous common series and therefore can
not be easily backported to stable.

There is a way to mark patch dependencies using Depends-on:
please use that instead of instructions to AI.

AI says that in its usual over the top wordy way...

Patch 3/3 - common/sfc_efx/base: fix reading advertised autoneg ability

  Warning: this patch depends on the pending common/sfc series for its
  diff context only, and that dependency creates a backport conflict.

  The efx_np.c hunk removes

      if (lsp->enls_an_supported != B_FALSE)
              lsp->enls_adv_cap_mask |= 1U << EFX_PHY_CAP_AN;

  from a position after the LINK_STATE_OUT_ADVERTISED_ABILITIES
  conversion.  On main and on every stable branch the block is still
  before that conversion, where 06f569de6c06 originally put it.  Since
  efx_np_cap_mask_hw_to_sw() ORs into *sw_cap_maskp (efx_np.c:197)
  rather than assigning, the block's position has no effect on the
  resulting mask - the pending series is only moving text.

  Both Fixes: commits first appear in v25.07, so this needs to reach
  25.11 LTS and 25.07, neither of which has the move.  Stable will hit
  a conflict on a hunk whose resolution is not obvious from the diff.

  Suggest sending this fix ahead of the series that moves the block,
  or as a standalone patch against main.  It then applies unchanged
  everywhere, and the other series absorbs a zero-cost rebase.  If the
  current ordering has to stand, please post an explicit backport to
  stable at dpdk.org rather than leaving the resolution to the stable
  maintainer.

  Info: the added local

      const efx_port_t *port = &enp->en_port;

  is used once, and the file otherwise reaches through enp->en_port
  directly (line 33) or names the local "epp" (medford4_phy_reconfigure,
  medford4_mac_poll).  Suggest:

      preserve_an = enp->en_port.ep_adv_cap_mask &
                    (1U << EFX_PHY_CAP_AN);