Re: [PATCH v2 0/9] ENETC driver related changes series

[Stephen Hemminger <stephen@networkplumber.org>]

On Mon, 22 Jun 2026 17:05:08 +0530
Gagandeep Singh <g.singh@nxp.com> wrote:

> V2 changes:
>   - Fixed an un-used variable compilation issue reported on fedora:43-gcc-minsize
>   - Fixed various AI reported issues:
> 	- Release notes updated for all new devargs
> 	- enect4.ini features doc updated for scattered RX.
> 	- removed Not required RTE_PTYPE_UNKNOWN.
> 	- Fixed mid-frame mbuf leak in SG case.
> 	- Enabled SG for enetc4 PF also.
> 	- move to calloc from rte_zmalloc in parse_txq_prior().
> 	- added vaidation checks on strdup, strtoul.
> 	- added NC devargs to use cacheable ops conditionally.
> 	- removed dead code like bd_base_p etc.
> 	- Fixed rte_cpu_to_le_16() conversion on flags and combined
> 	  all flags related patches in one patch.
> 	- Fixed memory leak issue due to TXQ priority patch.
>    - There were some false positives, I have ignored them:
> 	Race condition on flags field:
> 		clean_tx_ring only touches HW-completed BDs (next_to_clean→hwci),
> 		never newly-submitted BDs; doorbell hasn't fired yet.
> 	Missing dcbf in clean_tx_ring:
> 		DPDK is single-threaded per queue; TX path always overwrites
> 		flags completely before dcbf.
> 	TX dcbf granularity with wrap:
> 		Safe (AI admits it).
> 	RX refill flush at wrap:
> 		In-loop dcbf at i & mask == 0 already flushes aligned groups;
> 		trailing flush only needed for partial groups.
> 	RX reading before invalidate:
> 		dccivac precedes the read for every group in the loop
> 
> Gagandeep Singh (7):
>   net/enetc: fix TX BD structure
>   net/enetc: fix queue initialization
>   net/enetc: support ESP packet type in packet parsing
>   net/enetc: update random MAC generation code
>   net/enetc: add option to disable VSI messaging
>   net/enetc: add devargs to control VSI-PSI timeout and delay
>   net/enetc4: add cacheable BD ring support with SW cache maintenance
> 
> Vanshika Shukla (2):
>   net/enetc: support scatter-gather
>   net/enetc: set user configurable priority to TX rings
> 
>  doc/guides/nics/features/enetc4.ini    |   1 +
>  doc/guides/rel_notes/release_26_07.rst |  10 +
>  drivers/net/enetc/base/enetc_hw.h      |  13 +-
>  drivers/net/enetc/enetc.h              |  31 +-
>  drivers/net/enetc/enetc4_ethdev.c      | 172 ++++++++--
>  drivers/net/enetc/enetc4_vf.c          | 204 ++++++++++--
>  drivers/net/enetc/enetc_ethdev.c       |  25 +-
>  drivers/net/enetc/enetc_rxtx.c         | 430 ++++++++++++++++++++++---
>  8 files changed, 768 insertions(+), 118 deletions(-)
> 

Better but still had some AI feedback if I asked it for more complete review.
Agree that putting new devargs in doc is needed.

Error
=====

[PATCH v2 7/9] net/enetc: add devargs to control VSI-PSI timeout and delay

drivers/net/enetc/enetc4_vf.c, enetc4_vf_dev_init()

  kvlist is leaked on the two invalid-value error paths. It is
  allocated by rte_kvargs_parse() (line 1347) and only freed at
  line 1385, but both

      return -1;   /* invalid VSI Timeout, line 1367 */
      return -1;   /* invalid VSI Delay,   line 1380 */

  return before that free. A malformed enetc4_vsi_timeout= or
  enetc4_vsi_delay= leaks the kvargs structure on every probe.

  Free before returning, e.g.:

      if (errno != 0 || hw->vsi_timeout == 0) {
              ENETC_PMD_ERR("Invalid VSI Timeout value = %u",
                              hw->vsi_timeout);
              rte_kvargs_free(kvlist);
              return -1;
      }

  (same for the delay path), or restructure with a goto.


Warning
=======

Series (patches 6-9)

  The new runtime devargs - enetc4_vsi_disable, enetc4_vsi_timeout,
  enetc4_vsi_delay, enetc4_txq_prior, and nc - are registered via
  RTE_PMD_REGISTER_PARAM_STRING and noted in the release notes, but
  doc/guides/nics/enetc4.rst has no Runtime Configuration section
  describing them. Convention is to document devargs in the NIC guide
  so users can find the syntax (e.g. the nc=1 / 'a|b|c' priority list
  formats are non-obvious).

Info
====

[PATCH v2 5/9] and [PATCH v2 9/9] - RX multi-segment reassembly

  In enetc_clean_rx_ring_nc() and enetc_clean_rx_ring_cacheable(),
  on the frame-last BD:

      first_seg->pkt_len -= rx_ring->crc_len;

  reduces pkt_len but leaves the final segment's data_len unchanged,
  so pkt_len != sum(data_len) when crc_len is non-zero. The old
  single-segment path kept them equal (pkt_len = data_len = buf_len
  - crc_len).

  This is currently unreachable: enetc4 does not advertise
  RTE_ETH_RX_OFFLOAD_KEEP_CRC, so crc_len is always 0 and the
  subtraction is a no-op. Flagging only so the asymmetry is on record
  if KEEP_CRC is ever added - at that point the last segment's
  data_len would need the same adjustment (and the CRC may straddle
  the last two segments).