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

[Alexey Kuznetsov]

Ack to all

On Wed, Sep 16, 2026 at 11:41 PM Konstantin Khorenko
<khorenko at virtuozzo.com> wrote:
>
> 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>