From: David Woodhouse <dwmw@xxxxxxxxxxxx> The IOAPIC Redirection Table Entries contain an 8-bit Extended Destination ID field which maps to bits 11-4 of the MSI address. The lowest bit is used to indicate remappable format, when interrupt remapping is in use. A hypervisor can use the other 7 bits to permit guests to address up to 15 bits of APIC IDs, thus allowing 32768 vCPUs before having to expose a vIOMMU and interrupt remapping to the guest. No behavioural change in this patch, since nothing yet permits APIC IDs above 255 to be used with the non-IR IOAPIC domain. Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx> --- arch/x86/include/asm/io_apic.h | 3 ++- arch/x86/kernel/apic/io_apic.c | 19 +++++++++++++------ 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/io_apic.h b/arch/x86/include/asm/io_apic.h index a1a26f6d3aa4..e65a0b7379d0 100644 --- a/arch/x86/include/asm/io_apic.h +++ b/arch/x86/include/asm/io_apic.h @@ -78,7 +78,8 @@ struct IO_APIC_route_entry { mask : 1, /* 0: enabled, 1: disabled */ __reserved_2 : 15; - __u32 __reserved_3 : 24, + __u32 __reserved_3 : 17, + ext_dest : 7, dest : 8; } __attribute__ ((packed)); diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index a33380059db6..aa9a3b54a96c 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1239,10 +1239,10 @@ static void io_apic_print_entries(unsigned int apic, unsigned int nr_entries) buf, (ir_entry->index2 << 15) | ir_entry->index, ir_entry->zero); else - printk(KERN_DEBUG "%s, %s, D(%02X), M(%1d)\n", + printk(KERN_DEBUG "%s, %s, D(%02X%02X), M(%1d)\n", buf, entry.dest_mode == IOAPIC_DEST_MODE_LOGICAL ? - "logical " : "physical", + "logical " : "physical", entry.ext_dest, entry.dest, entry.delivery_mode); } } @@ -1410,6 +1410,7 @@ void native_restore_boot_irq_mode(void) */ if (ioapic_i8259.pin != -1) { struct IO_APIC_route_entry entry; + u32 apic_id = read_apic_id(); memset(&entry, 0, sizeof(entry)); entry.mask = IOAPIC_UNMASKED; @@ -1417,7 +1418,8 @@ void native_restore_boot_irq_mode(void) entry.polarity = IOAPIC_POL_HIGH; entry.dest_mode = IOAPIC_DEST_MODE_PHYSICAL; entry.delivery_mode = dest_ExtINT; - entry.dest = read_apic_id(); + entry.dest = apic_id & 0xff; + entry.ext_dest = apic_id >> 8; /* * Add it to the IO-APIC irq-routing table: @@ -1861,7 +1863,8 @@ static void ioapic_configure_entry(struct irq_data *irqd) * ioapic chip to verify that. */ if (irqd->chip == &ioapic_chip) { - mpd->entry.dest = cfg->dest_apicid; + mpd->entry.dest = cfg->dest_apicid & 0xff; + mpd->entry.ext_dest = cfg->dest_apicid >> 8; mpd->entry.vector = cfg->vector; } for_each_irq_pin(entry, mpd->irq_2_pin) @@ -2027,6 +2030,7 @@ static inline void __init unlock_ExtINT_logic(void) int apic, pin, i; struct IO_APIC_route_entry entry0, entry1; unsigned char save_control, save_freq_select; + u32 apic_id; pin = find_isa_irq_pin(8, mp_INT); if (pin == -1) { @@ -2042,11 +2046,13 @@ static inline void __init unlock_ExtINT_logic(void) entry0 = ioapic_read_entry(apic, pin); clear_IO_APIC_pin(apic, pin); + apic_id = hard_smp_processor_id(); memset(&entry1, 0, sizeof(entry1)); entry1.dest_mode = IOAPIC_DEST_MODE_PHYSICAL; entry1.mask = IOAPIC_UNMASKED; - entry1.dest = hard_smp_processor_id(); + entry1.dest = apic_id & 0xff; + entry1.ext_dest = apic_id >> 8; entry1.delivery_mode = dest_ExtINT; entry1.polarity = entry0.polarity; entry1.trigger = IOAPIC_EDGE; @@ -2949,7 +2955,8 @@ static void mp_setup_entry(struct irq_cfg *cfg, struct mp_chip_data *data, memset(entry, 0, sizeof(*entry)); entry->delivery_mode = apic->irq_delivery_mode; entry->dest_mode = apic->irq_dest_mode; - entry->dest = cfg->dest_apicid; + entry->dest = cfg->dest_apicid & 0xff; + entry->ext_dest = cfg->dest_apicid >> 8; entry->vector = cfg->vector; entry->trigger = data->trigger; entry->polarity = data->polarity; -- 2.26.2