diff options
| -rw-r--r-- | drivers/irqchip/irq-gic-v3.c | 14 | ||||
| -rw-r--r-- | include/linux/acpi.h | 3 |
2 files changed, 16 insertions, 1 deletions
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 0f54811262eb..f56d064f4aa9 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -2365,11 +2365,25 @@ gic_acpi_parse_madt_gicc(union acpi_subtable_headers *header, (struct acpi_madt_generic_interrupt *)header; u32 reg = readl_relaxed(acpi_data.dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK; u32 size = reg == GIC_PIDR2_ARCH_GICv4 ? SZ_64K * 4 : SZ_64K * 2; + int cpu = get_cpu_for_acpi_id(gicc->uid); void __iomem *redist_base; if (!acpi_gicc_is_usable(gicc)) return 0; + /* + * Capable but disabled CPUs can be brought online later. What about + * the redistributor? ACPI doesn't want to say! + * Virtual hotplug systems can use the MADT's "always-on" GICR entries. + * Otherwise, prevent such CPUs from being brought online. + */ + if (!(gicc->flags & ACPI_MADT_ENABLED)) { + pr_warn_once("CPU %u's redistributor is inaccessible: this CPU can't be brought online\n", cpu); + set_cpu_present(cpu, false); + set_cpu_possible(cpu, false); + return 0; + } + redist_base = ioremap(gicc->gicr_base_address, size); if (!redist_base) return -ENOMEM; diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 584ebec7f7f1..c3fc608af6d4 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -258,7 +258,8 @@ void acpi_table_print_madt_entry (struct acpi_subtable_header *madt); static inline bool acpi_gicc_is_usable(struct acpi_madt_generic_interrupt *gicc) { - return (gicc->flags & ACPI_MADT_ENABLED); + return ((gicc->flags & ACPI_MADT_ENABLED || + gicc->flags & ACPI_MADT_GICC_CPU_CAPABLE)); } /* the following numa functions are architecture-dependent */ |