[Devel] [PATCH vz10 v2 0/3] Restore ConnectX-3 Pro support dropped by RHEL 10

[Konstantin Khorenko]

RHEL 10 removed the mlx4 driver: CONFIG_MLX4_CORE is off on every
architecture but aarch64, and the whole ConnectX-3 family sits in
rh_disabled_pci_devices[], so local_pci_probe() answers -EACCES even
where the driver is built. A host whose only NIC is a ConnectX-3 Pro
cannot run a release kernel at all, which is what we hit on lab
equipment.

The removal follows NVIDIA ending vendor support for the hardware,
not any defect: the driver is maintained upstream, Fedora builds it,
and AlmaLinux 10 has already moved the same PCI IDs out of the
disabled list. The history is collected in the Jira issue below.

Patch 1 adds the skip_pci_blacklist option, so a host that hits the
blacklist on some other device can still be brought up, from an IPMI
console if need be.

Patch 2 moves 15b3:1007 (ConnectX-3 Pro) from the disabled list to
the unmaintained one, so the card is driven while the log keeps
saying that the hardware is untested.

Patch 3 builds mlx4 again, Ethernet and InfiniBand, without which the
first two patches change nothing on x86_64.

The rest of the mlx4 family and ConnectX-2 stay as RHEL left them.

https://virtuozzo.atlassian.net/browse/VSTOR-145697

Changes in v2:
- split the single patch into the option, the PCI ID and the config
- report a bypassed device as unmaintained rather than deprecated:
  "deprecated" promises support that exists today, which is not true
  for a device RHEL has already disabled
- move 15b3:1007 into rh_unmaintained_pci_devices[] instead of
  deleting it, so the card is still reported, the way AlmaLinux does
- keep skip_pci_blacklist and its core_param() next to their only
  user, inside #ifdef CONFIG_PCI
- document skip_pci_blacklist in kernel-parameters.txt
- enable CONFIG_MLX4_CORE, CONFIG_MLX4_EN and CONFIG_MLX4_INFINIBAND
  in custom-overrides: RHEL 10 does not build mlx4 on x86_64, so v1
  had no effect there
- Link to v1: http://lore.virtuozzo.com/aqlsDIyP9+pTstGU@mops2
  Message-Id: <aqlsDIyP9+pTstGU at mops2>
  [Devel] [PATCH VZ10] core: allow to bypass rhel pci blacklist

Signed-off-by: Konstantin Khorenko <khorenko at virtuozzo.com>
---
Alexey Kuznetsov (2):
      core: add skip_pci_blacklist option to probe RHEL-disabled devices
      core: allow ConnectX-3 Pro to probe, as unmaintained hardware

Konstantin Khorenko (1):
      configs: build the mlx4 driver, Ethernet and InfiniBand

 Documentation/admin-guide/kernel-parameters.txt              | 12 ++++++++++++
 kernel/rh_messages.c                                         |  9 +++++++++
 kernel/rh_messages.h                                         |  2 +-
 redhat/configs/custom-overrides/generic/CONFIG_MLX4_CORE     |  1 +
 redhat/configs/custom-overrides/generic/CONFIG_MLX4_EN       |  1 +
 .../configs/custom-overrides/generic/CONFIG_MLX4_INFINIBAND  |  1 +
 6 files changed, 25 insertions(+), 1 deletion(-)
---
base-commit: 3fff8724d1f894459c1477990fe086c0c2573410
change-id: 20260916-b4-prep-khorenko-vstor-145697-mlx4-7d6927d60446

Best regards,
--  
Konstantin Khorenko <khorenko at virtuozzo.com>