Re: [PATCH][4.16] x86/x2APIC: defer probe until after IOMMU ACPI table parsing [and 1 more messages]

[Ian Jackson <iwj@xxxxxxxxxxxxxx>]

Jan Beulich writes ("[PATCH][4.16] x86/x2APIC: defer probe until after IOMMU 
ACPI table parsing"):
> While commit XXXXXXXXXXXX ("x86/IOMMU: mark IOMMU / intremap not in use
> when ACPI tables are missing") deals with apic_x2apic_probe() as called
> from x2apic_bsp_setup(), the check_x2apic_preenabled() path is similarly
> affected: The call needs to occur after acpi_boot_init() (which is what
> calls acpi_iommu_init()), such that iommu_intremap getting disabled
> there can be properly taken into account by apic_x2apic_probe().
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
> ---
> Based on code inspection only - I have no affected system and hence no
> way to actually test the case.

Do we have any tests for this ?  I see it's tagged for 4.16 (and I'm
favourably inclined) but I'm not sure I follow the implications.

Roger Pau Monné writes ("Re: [PATCH][4.16] x86/x2APIC: defer probe until after 
IOMMU ACPI table parsing"):
> LGTM. I cannot find any dependency between acpi_boot_init and having
> initialized the apic.
> 
> Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>

Thanks,
Ian.