Re: [PATCH v2] x86/PCI: Improve log message when IRQ cannot be identified

[Maciej W. Rozycki]

On Thu, 3 Feb 2022, Brent Spillner wrote:

> > If your system has ACPI, I think "pci=biosirq" and "acpi=noirq" are at
> > best distractions from finding the real problem.
> 
> ...except when the cause is indeed buggy ACPI firmware, which is
> presumably the only reason these options exist in the first place.

 The former is really for us missing a PIRQ router or for a BIOS missing a 
$PIR table.  I have been posting patches recently to add support for some 
of such systems identified.  Those are all pre-ACPI, possibly long before, 
i.e. early to late 1990s (486 and P5/P54C Pentium and similar systems), 
and I think the option was added before we had ACPI support too.  I have a 
couple of pre-ACPI x86 systems too, which are quirky to say the least even 
though they were the quality systems of the time from reputable vendors.

 FWIW,

  Maciej