On 2024/6/5 18:09, Jan Beulich wrote: > On 05.06.2024 09:04, Chen, Jiqian wrote: >> On 2024/6/5 01:17, Jan Beulich wrote: >>> On 04.06.2024 10:18, Chen, Jiqian wrote: >>>> I tried to get more debug information from my environment. And I attach >>>> them here, maybe you can find some problems. >>>> acpi_parse_madt_ioapic_entries >>>> acpi_table_parse_madt(ACPI_MADT_TYPE_INTERRUPT_OVERRIDE, >>>> acpi_parse_int_src_ovr, MAX_IRQ_SOURCES); >>>> acpi_parse_int_src_ovr >>>> mp_override_legacy_irq >>>> only process two entries, irq 0 gsi 2 and irq 9 >>>> gsi 9 >>>> There are only two entries whose type is ACPI_MADT_TYPE_INTERRUPT_OVERRIDE >>>> in MADT table. Is it normal? >>> >>> Yes, that's what you'd typically see (or just one such entry). >> Ok, let me conclude that acpi_parse_int_src_ovr get two entries from MADT >> table and add them into mp_irqs. They are [irq, gsi][0, 2] and [irq, gsi][9, >> 9]. >> Then in the following function mp_config_acpi_legacy_irqs initializes the >> 1:1 mapping of irq and gsi [0~15 except 2 and 9], and add them into mp_irqs. >> But for high GSIs(>= 16), no mapping processing. >> Right? > > On that specific system of yours - yes. In the general case high GSIs > may have entries, too. > >> Is it that the Xen hypervisor lacks some handling of high GSIs? > > I don't think so. Unless you can point out something? Ok, so the implementation is still to get mapping from mp_irqs, I will change in next version. Thank you.
> >> For now, if hypervisor gets a high GSIs, it can't be transformed to irq, >> because there is no mapping between them. > > No, in the absence of a source override (note the word "override") the > default identity mapping applies. What is identity mapping? Like the mp_config_acpi_legacy_irqs does? > > Jan -- Best regards, Jiqian Chen.
