Re: [PATCH v5 0/7] multi-process and VF hotplug fixes

Stephen Hemminger
2026-02-28T17:03:43Z

On Thu, 26 Feb 2026 17:59:20 -0800
Long Li <longli@microsoft.com> wrote:

> Fix several issues with VF hotplug and multi-process support in
> netvsc, mana, mlx5, and mlx4 drivers:
>
> - Fix race conditions between VSP notifications and DPDK device events
> during VF add/remove, with proper locking of VF-related fields
> - Add multi-process communication infrastructure for coordinating VF
> removal across primary and secondary processes
> - Fix Protection Domain resource leak on device close in mana
> - Fix devargs memory leak during VF hotplug in netvsc
> - Fix fast-path ops (rte_eth_fp_ops) setup in secondary processes for
> mana, mlx5, and mlx4, ensuring burst function pointers are restored
> after STOP->START cycles
>
> v5:
> - Patches 5,6,7: Also restore rte_eth_fp_ops burst function pointers
> (rx_pkt_burst, tx_pkt_burst) in START_RXTX handler, not just queue
> data pointers. Without this, after a STOP->START cycle the secondary
> process burst pointers remain set to dummy functions.
>
> v4:
> - Patch 1: Check hn_vf_add() return value in netvsc_hotplug_retry
> - Patch 1: Track fresh_attach to avoid tearing down original VF
> attachment when configure/start fails on an -EEXIST path
> - Patch 2: Move counter decrement and netvsc_uninit_once() after device
> cleanup in eth_hn_remove() to prevent use-after-free of shared data
> - Patch 2: Clear netvsc_shared_data on init failure paths to prevent
> dangling pointer
>
> v3:
> - Fix review comments from v2
>
> v2:
> - Initial rework of VF add/remove locking
>
> Long Li (7):
> net/netvsc: fix race conditions on VF add/remove events
> net/netvsc: add multi-process VF device removal support
> net/mana: fix PD resource leak on device close
> net/netvsc: fix devargs memory leak on hotplug
> net/mana: fix fast-path ops setup in secondary process
> net/mlx5: fix fast-path ops setup in secondary process
> net/mlx4: fix fast-path ops setup in secondary process
>
> drivers/net/mana/mana.c | 14 ++
> drivers/net/mana/mp.c | 8 +
> drivers/net/mlx4/mlx4_mp.c | 6 +
> drivers/net/mlx5/linux/mlx5_mp_os.c | 6 +
> drivers/net/netvsc/hn_ethdev.c | 300 +++++++++++++++++++++++++++-
> drivers/net/netvsc/hn_nvs.h | 6 +
> drivers/net/netvsc/hn_rxtx.c | 40 ++--
> drivers/net/netvsc/hn_var.h | 1 +
> drivers/net/netvsc/hn_vf.c | 148 ++++++++------
> 9 files changed, 437 insertions(+), 92 deletions(-)

Applied to next-net.
The SHA hashes of those fixes tags was off; fixed them by
matching on the subject.

Also fixed a couple checkpatch warnings for:

CHECK:OPEN_ENDED_LINE: Lines should not end with a '('
#295: FILE: drivers/net/netvsc/hn_ethdev.c:1763:
+ rte_atomic_fetch_add_explicit(