[ofa-general] Re: [PATCH V2] IB/mlx4: enable MSI-X by default

[Roland Dreier]

 >  		mlx4_err(dev, "NOP command failed to generate interrupt "
 >  			 "(IRQ %d), aborting.\n",
 >  			 priv->eq_table.eq[MLX4_EQ_ASYNC].irq);
 > -		if (dev->flags & MLX4_FLAG_MSI_X)
 > -			mlx4_err(dev, "Try again with MSI-X disabled.\n");
 > -		else
 > -			mlx4_err(dev, "BIOS or ACPI interrupt routing problem?\n");
 > +		mlx4_err(dev, "BIOS or ACPI interrupt routing problem?\n");

This means that if MSI-X doesn't work on a system, then the user will
see something like

    <dev> NOP command failed to generate interrupt (IRQ XXX), aborting.
    <dev> BIOS or ACPI interrupt routing problem?

but then things will probably go on and work, right?

Which seems quite confusing.

I think the code should be changed so that the message above is
displayed (as before) if INTx interrupts fail, but if MSI-X fails,
then do something like

	mlx4_warn(dev, "MSI-X did not work; trying legacy INTx interrupt.\n");

(and similarly for mthca too).