diff options
Diffstat (limited to 'arch/x86/kernel/setup.c')
| -rw-r--r-- | arch/x86/kernel/setup.c | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index bbfbca5fea0c..4cfba947d774 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -985,6 +985,30 @@ void __init setup_arch(char **cmdline_p) parse_early_param(); +#ifdef CONFIG_MEMORY_HOTPLUG + /* + * Memory used by the kernel cannot be hot-removed because Linux + * cannot migrate the kernel pages. When memory hotplug is + * enabled, we should prevent memblock from allocating memory + * for the kernel. + * + * ACPI SRAT records all hotpluggable memory ranges. But before + * SRAT is parsed, we don't know about it. + * + * The kernel image is loaded into memory at very early time. We + * cannot prevent this anyway. So on NUMA system, we set any + * node the kernel resides in as un-hotpluggable. + * + * Since on modern servers, one node could have double-digit + * gigabytes memory, we can assume the memory around the kernel + * image is also un-hotpluggable. So before SRAT is parsed, just + * allocate memory near the kernel image to try the best to keep + * the kernel away from hotpluggable memory. + */ + if (movable_node_is_enabled()) + memblock_set_bottom_up(true); +#endif + x86_report_nx(); /* after early param, so could get panic from serial */ @@ -1221,11 +1245,16 @@ void __init setup_arch(char **cmdline_p) */ get_smp_config(); + /* + * Systems w/o ACPI and mptables might not have it mapped the local + * APIC yet, but prefill_possible_map() might need to access it. + */ + init_apic_mappings(); + prefill_possible_map(); init_cpu_to_node(); - init_apic_mappings(); io_apic_init_mappings(); kvm_guest_init(); |
