1 files changed, 47 insertions, 19 deletions

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 98c9cd6f3b5d..4cfba947d774 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -210,9 +210,9 @@ EXPORT_SYMBOL(boot_cpu_data);
 
 
 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
-__visible unsigned long mmu_cr4_features;
+__visible unsigned long mmu_cr4_features __ro_after_init;
 #else
-__visible unsigned long mmu_cr4_features = X86_CR4_PAE;
+__visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE;
 #endif
 
 /* Boot loader ID and version as integers, for the benefit of proc_dointvec */
@@ -458,8 +458,8 @@ static void __init e820_reserve_setup_data(void)
 		early_memunmap(data, sizeof(*data));
 	}
 
-	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
-	memcpy(&e820_saved, &e820, sizeof(struct e820map));
+	sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
+	memcpy(e820_saved, e820, sizeof(struct e820map));
 	printk(KERN_INFO "extended physical RAM map:\n");
 	e820_print_map("reserve setup_data");
 }
@@ -763,7 +763,7 @@ static void __init trim_bios_range(void)
 	 */
 	e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1);
 
-	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+	sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
 }
 
 /* called before trim_bios_range() to spare extra sanitize */
@@ -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 */
@@ -1032,7 +1056,7 @@ void __init setup_arch(char **cmdline_p)
 	if (ppro_with_ram_bug()) {
 		e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
 				  E820_RESERVED);
-		sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+		sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
 		printk(KERN_INFO "fixed physical RAM map:\n");
 		e820_print_map("bad_ppro");
 	}
@@ -1096,19 +1120,19 @@ void __init setup_arch(char **cmdline_p)
 	memblock_set_current_limit(ISA_END_ADDRESS);
 	memblock_x86_fill();
 
-	if (efi_enabled(EFI_BOOT)) {
+	reserve_bios_regions();
+
+	if (efi_enabled(EFI_MEMMAP)) {
 		efi_fake_memmap();
 		efi_find_mirror();
-	}
-
-	reserve_bios_regions();
+		efi_esrt_init();
 
-	/*
-	 * The EFI specification says that boot service code won't be called
-	 * after ExitBootServices(). This is, in fact, a lie.
-	 */
-	if (efi_enabled(EFI_MEMMAP))
+		/*
+		 * The EFI specification says that boot service code won't be
+		 * called after ExitBootServices(). This is, in fact, a lie.
+		 */
 		efi_reserve_boot_services();
+	}
 
 	/* preallocate 4k for mptable mpc */
 	early_reserve_e820_mpc_new();
@@ -1137,7 +1161,7 @@ void __init setup_arch(char **cmdline_p)
 	 * auditing all the early-boot CR4 manipulation would be needed to
 	 * rule it out.
 	 */
-	mmu_cr4_features = __read_cr4_safe();
+	mmu_cr4_features = __read_cr4();
 
 	memblock_set_current_limit(get_max_mapped());
 
@@ -1219,14 +1243,18 @@ void __init setup_arch(char **cmdline_p)
 	/*
 	 * get boot-time SMP configuration:
 	 */
-	if (smp_found_config)
-		get_smp_config();
+	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();