Reserve the running BSP as kernel ID 0 before the MADT walk, so it
survives firmware that lists it later. Ignore duplicate LAPIC entries
and CPUs beyond NCPUS, count eligible against accepted CPUs, and handle
x2APIC and NMI source entries instead of printing them as unhandled.
Stop the walk on a zero-length or truncated entry, and name the ACPI
error codes for the startup path.
---
i386/i386at/acpi_parse_apic.c | 105 +++++++++++++++++++++++++++-------
i386/i386at/acpi_parse_apic.h | 4 +-
2 files changed, 86 insertions(+), 23 deletions(-)
diff --git a/i386/i386at/acpi_parse_apic.c b/i386/i386at/acpi_parse_apic.c
index 848585c..5edf76a 100644
--- a/i386/i386at/acpi_parse_apic.c
+++ b/i386/i386at/acpi_parse_apic.c
@@ -36,6 +36,23 @@ static struct acpi_apic *apic_madt = NULL;
unsigned lapic_addr;
uint32_t *hpet_addr;
+const char *
+acpi_error_string(int err)
+{
+ switch (err) {
+ case ACPI_BAD_CHECKSUM: return "bad ACPI table checksum";
+ case ACPI_BAD_ALIGN: return "bad ACPI RSDP alignment";
+ case ACPI_NO_RSDP: return "no ACPI RSDP found";
+ case ACPI_NO_RSDT: return "no ACPI RSDT/XSDT found";
+ case ACPI_BAD_SIGNATURE: return "bad ACPI table signature";
+ case ACPI_NO_APIC: return "no APIC/MADT table found";
+ case ACPI_NO_LAPIC: return "cannot map the Local APIC";
+ case ACPI_APIC_FAILURE: return "no usable APIC CPU topology";
+ case ACPI_FIT_FAILURE: return "cannot size the accepted CPU list";
+ default: return "unknown ACPI/APIC error";
+ }
+}
+
/*
* acpi_print_info: shows by screen the ACPI's rsdp and rsdt virtual address
* and the number of entries stored in RSDT table.
@@ -371,16 +388,28 @@ acpi_get_apic2(struct acpi_xsdt *xsdt, int acpi_xsdt_n)
* and increase the number of cpus.
*
* Receives as input the Local APIC entry in MADT/APIC table.
+ * Duplicate entries and CPUs beyond NCPUS are ignored.
*/
static void
acpi_apic_add_lapic(struct acpi_apic_lapic *lapic_entry)
{
+ uint16_t apic_id;
+ int i;
+
/* If cpu flag is correct */
- if (lapic_entry->flags & (ACPI_LAPIC_FLAG_ENABLED |
ACPI_LAPIC_FLAG_CAPABLE)) {
- /* Add cpu to processors' list. */
- apic_add_cpu(lapic_entry->apic_id & apic_id_mask);
+ if (!(lapic_entry->flags & (ACPI_LAPIC_FLAG_ENABLED |
ACPI_LAPIC_FLAG_CAPABLE)))
+ return;
+
+ apic_id = lapic_entry->apic_id & apic_id_mask;
+
+ for (i = 0; i < apic_get_numcpus(); i++) {
+ if (apic_get_cpu_apic_id(i) == apic_id)
+ return;
}
+ if (apic_add_cpu(apic_id) != 0)
+ printf("APIC: ignoring LAPIC ID %#x: NCPUS=%d limit reached\n",
+ apic_id, NCPUS);
}
/*
@@ -445,7 +474,7 @@ acpi_apic_parse_table(struct acpi_apic *apic)
{
struct acpi_apic_dhdr *apic_entry = NULL;
vm_offset_t end = 0;
- uint8_t numcpus = 1;
+ unsigned int eligible = 0;
/* Get the address of first APIC entry */
apic_entry = (struct acpi_apic_dhdr*) apic->entry;
@@ -455,26 +484,29 @@ acpi_apic_parse_table(struct acpi_apic *apic)
printf("APIC entry=0x%p end=0x%x\n", apic_entry, end);
- /* Initialize number of cpus */
- numcpus = apic_get_numcpus();
-
- /* Search in APIC entry. */
- while ((vm_offset_t)apic_entry < end) {
+ /* Stop on a truncated or zero-length entry. */
+ while ((vm_offset_t)apic_entry + sizeof(struct acpi_apic_dhdr) <= end) {
struct acpi_apic_lapic *lapic_entry;
struct acpi_apic_ioapic *ioapic_entry;
struct acpi_apic_irq_override *irq_override_entry;
printf("APIC entry=0x%p end=0x%x\n", apic_entry, end);
+
+ if (apic_entry->length == 0) {
+ printf("APIC: zero-length MADT entry type %#x, stopping\n",
+ apic_entry->type);
+ break;
+ }
+
/* Check entry type. */
switch(apic_entry->type) {
/* If APIC entry is a CPU's Local APIC. */
case ACPI_APIC_ENTRY_LAPIC:
- if(numcpus < NCPUS) {
- /* Store Local APIC data. */
- lapic_entry = (struct acpi_apic_lapic*) apic_entry;
- acpi_apic_add_lapic(lapic_entry);
- }
+ lapic_entry = (struct acpi_apic_lapic*) apic_entry;
+ if (lapic_entry->flags & (ACPI_LAPIC_FLAG_ENABLED |
ACPI_LAPIC_FLAG_CAPABLE))
+ eligible++;
+ acpi_apic_add_lapic(lapic_entry);
break;
/* If APIC entry is an IOAPIC. */
@@ -494,20 +526,31 @@ acpi_apic_parse_table(struct acpi_apic *apic)
acpi_apic_add_irq_override(irq_override_entry);
break;
+ /* x2APIC entries hold 32-bit IDs this xAPIC port cannot map. */
+ case ACPI_APIC_ENTRY_X2APIC:
+ printf("APIC: x2APIC entry (type %d) unsupported, ignored\n",
+ apic_entry->type);
+ break;
+
+ /* Local APIC NMI entries do not describe a processor. */
+ case ACPI_APIC_ENTRY_NONMASK_IRQ:
+ break;
+
/* FIXME: There is another unhandled case */
- default:
- printf("Unhandled APIC entry type 0x%x\n", apic_entry->type);
- break;
+ default:
+ printf("Unhandled APIC entry type 0x%x\n", apic_entry->type);
+ break;
}
/* Get next APIC entry. */
apic_entry = (struct acpi_apic_dhdr*)((vm_offset_t) apic_entry
+ apic_entry->length);
-
- /* Update number of cpus. */
- numcpus = apic_get_numcpus();
}
+ if (eligible > apic_get_numcpus())
+ printf("APIC: %u eligible LAPIC entries, accepted %u (NCPUS=%d)\n",
+ eligible, apic_get_numcpus(), NCPUS);
+
return ACPI_SUCCESS;
}
@@ -544,19 +587,37 @@ acpi_apic_setup(struct acpi_apic *apic)
fix_apic_id_mask();
+ /* The BSP must keep kernel ID 0; reserve it before the MADT walk. */
+ if (apic_add_cpu(apic_get_current_cpu()) != 0)
+ return ACPI_APIC_FAILURE;
+
acpi_apic_parse_table(apic);
ncpus = apic_get_numcpus();
nioapics = apic_get_num_ioapics();
- if (ncpus == 0 || nioapics == 0 || ncpus > NCPUS)
+ if (ncpus == 0) {
+ printf("ACPI: no usable Local APIC (NCPUS=%d)\n", NCPUS);
+ return ACPI_APIC_FAILURE;
+ }
+
+ if (ncpus > NCPUS) {
+ printf("ACPI: %u accepted CPUs exceed NCPUS=%d\n", ncpus, NCPUS);
return ACPI_APIC_FAILURE;
+ }
+
+ if (nioapics == 0) {
+ printf("ACPI: no IOAPIC in MADT\n");
+ return ACPI_APIC_FAILURE;
+ }
/* Refit the apic-cpu array. */
if(ncpus < NCPUS) {
int refit = apic_refit_cpulist();
- if (refit != 0)
+ if (refit != 0) {
+ printf("ACPI: cannot shrink CPU list to %u entries\n", ncpus);
return ACPI_FIT_FAILURE;
+ }
}
apic_generate_cpu_id_lut();
diff --git a/i386/i386at/acpi_parse_apic.h b/i386/i386at/acpi_parse_apic.h
index df8d4ba..c8cf833 100644
--- a/i386/i386at/acpi_parse_apic.h
+++ b/i386/i386at/acpi_parse_apic.h
@@ -107,7 +107,8 @@ enum ACPI_APIC_ENTRY_TYPE {
ACPI_APIC_ENTRY_LAPIC = 0,
ACPI_APIC_ENTRY_IOAPIC = 1,
ACPI_APIC_ENTRY_IRQ_OVERRIDE = 2,
- ACPI_APIC_ENTRY_NONMASK_IRQ = 4
+ ACPI_APIC_ENTRY_NONMASK_IRQ = 4,
+ ACPI_APIC_ENTRY_X2APIC = 9
};
/*
@@ -197,6 +198,7 @@ struct acpi_hpet {
int acpi_apic_init(void);
void acpi_print_info(phys_addr_t rsdp, void *rsdt, int acpi_rsdt_n);
+const char *acpi_error_string(int err);
extern unsigned lapic_addr;
