Configuring IRQ SMP affinity has no effect on some devices that use message
signalled interrupts (MSI) with no MSI per-vector masking capability. Examples of such devices include Broadcom NetXtreme Ethernet devices that use the bnx2 driver.
If you need to configure IRQ affinity for such a device, disable MSI by creating a file in /etc/modprobe.d/ containing the following line:
options bnx2 disable_msi=1
Alternatively, you can disable MSI completely using the kernel boot parameter pci=nomsi.