x86: move x86_64 gdt closer to i386 (a939098a) · Commits · 戴 / test

arch/x86/kernel/head_64.S

+5 −43

Original line number	Diff line number	Diff line
		@@ -203,7 +203,7 @@ ENTRY(secondary_startup_64)
		* addresses where we're currently running on. We have to do that here
		* because in 32bit we couldn't load a 64bit linear address.
		*/
		lgdt cpu_gdt_descr(%rip)
		lgdt early_gdt_descr(%rip)

		/* set up data segments. actually 0 would do too */
		movl $__KERNEL_DS,%eax
		@@ -391,53 +391,15 @@ NEXT_PAGE(level2_spare_pgt)

		.data
		.align 16
		.globl cpu_gdt_descr
		cpu_gdt_descr:
		.word gdt_end-cpu_gdt_table-1
		gdt:
		.quad cpu_gdt_table
		#ifdef CONFIG_SMP
		.rept NR_CPUS-1
		.word 0
		.quad 0
		.endr
		#endif
		.globl early_gdt_descr
		early_gdt_descr:
		.word GDT_ENTRIES*8-1
		.quad per_cpu__gdt_page

		ENTRY(phys_base)
		/* This must match the first entry in level2_kernel_pgt */
		.quad 0x0000000000000000

		/* We need valid kernel segments for data and code in long mode too
		* IRET will check the segment types kkeil 2000/10/28
		* Also sysret mandates a special GDT layout
		*/

		.section .data.page_aligned, "aw"
		.align PAGE_SIZE

		/* The TLS descriptors are currently at a different place compared to i386.
		Hopefully nobody expects them at a fixed place (Wine?) */

		ENTRY(cpu_gdt_table)
		.quad 0x0000000000000000 /* NULL descriptor */
		.quad 0x00cf9b000000ffff /* __KERNEL32_CS */
		.quad 0x00af9b000000ffff /* __KERNEL_CS */
		.quad 0x00cf93000000ffff /* __KERNEL_DS */
		.quad 0x00cffb000000ffff /* __USER32_CS */
		.quad 0x00cff3000000ffff /* __USER_DS, __USER32_DS */
		.quad 0x00affb000000ffff /* __USER_CS */
		.quad 0x0 /* unused */
		.quad 0,0 /* TSS */
		.quad 0,0 /* LDT */
		.quad 0,0,0 /* three TLS descriptors */
		.quad 0x0000f40000000000 /* node/CPU stored in limit */
		gdt_end:
		/* asm/segment.h:GDT_ENTRIES must match this */
		/* This should be a multiple of the cache line size */
		/* GDTs of other CPUs are now dynamically allocated */

		/* zero the remaining page */
		.fill PAGE_SIZE / 8 - GDT_ENTRIES,8,0

		.section .bss, "aw", @nobits
		.align L1_CACHE_BYTES

arch/x86/kernel/setup64.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -202,11 +202,8 @@ void __cpuinit cpu_init (void)
		* Initialize the per-CPU GDT with the boot GDT,
		* and set up the GDT descriptor:
		*/
		if (cpu)
		memcpy(get_cpu_gdt_table(cpu), cpu_gdt_table, GDT_SIZE);

		cpu_gdt_descr[cpu].size = GDT_SIZE;
		load_gdt((const struct desc_ptr *)&cpu_gdt_descr[cpu]);
		switch_to_new_gdt();
		load_idt((const struct desc_ptr *)&idt_descr);

		memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);

arch/x86/kernel/setup_64.c

+17 −2

Original line number	Diff line number	Diff line
		@@ -81,8 +81,6 @@
		#define ARCH_SETUP
		#endif

		#include "cpu/cpu.h"

		/*
		* Machine setup..
		*/
		@@ -228,6 +226,23 @@ static inline void copy_edd(void)
		}
		#endif

		/* Overridden in paravirt.c if CONFIG_PARAVIRT */
		void __attribute__((weak)) __init memory_setup(void)
		{
		machine_specific_memory_setup();
		}

		/* Current gdt points %fs at the "master" per-cpu area: after this,
		* it's on the real one. */
		void switch_to_new_gdt(void)
		{
		struct desc_ptr gdt_descr;

		gdt_descr.address = (long)get_cpu_gdt_table(smp_processor_id());
		gdt_descr.size = GDT_SIZE - 1;
		load_gdt(&gdt_descr);
		}

		/*
		* setup_arch - architecture-specific boot-time initializations
		*

arch/x86/kernel/smpboot.c

+3 −9

Original line number	Diff line number	Diff line
		@@ -849,14 +849,8 @@ static int __cpuinit do_boot_cpu(int apicid, int cpu)
		.done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
		};
		INIT_WORK(&c_idle.work, do_fork_idle);
		#ifdef CONFIG_X86_64
		/* allocate memory for gdts of secondary cpus. Hotplug is considered */
		if (!cpu_gdt_descr[cpu].address &&
		!(cpu_gdt_descr[cpu].address = get_zeroed_page(GFP_KERNEL))) {
		printk(KERN_ERR "Failed to allocate GDT for CPU %d\n", cpu);
		return -1;
		}

		#ifdef CONFIG_X86_64
		/* Allocate node local memory for AP pdas */
		if (cpu > 0) {
		boot_error = get_local_pda(cpu);
		@@ -898,7 +892,6 @@ do_rest:
		#ifdef CONFIG_X86_32
		per_cpu(current_task, cpu) = c_idle.idle;
		init_gdt(cpu);
		early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
		c_idle.idle->thread.ip = (unsigned long) start_secondary;
		/* Stack for startup_32 can be just as for start_secondary onwards */
		irq_ctx_init(cpu);
		@@ -908,6 +901,7 @@ do_rest:
		initial_code = (unsigned long)start_secondary;
		clear_tsk_thread_flag(c_idle.idle, TIF_FORK);
		#endif
		early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
		stack_start.sp = (void *) c_idle.idle->thread.sp;

		/* start_ip had better be page-aligned! */
		@@ -1252,8 +1246,8 @@ void __init native_smp_prepare_boot_cpu(void)
		int me = smp_processor_id();
		#ifdef CONFIG_X86_32
		init_gdt(me);
		switch_to_new_gdt();
		#endif
		switch_to_new_gdt();
		/* already set me in cpu_online_map in boot_cpu_init() */
		cpu_set(me, cpu_callout_map);
		per_cpu(cpu_state, me) = CPU_ONLINE;

arch/x86/kernel/x8664_ksyms_64.c

+0 −5

Original line number	Diff line number	Diff line
		@@ -53,8 +53,3 @@ EXPORT_SYMBOL(init_level4_pgt);
		EXPORT_SYMBOL(load_gs_index);

		EXPORT_SYMBOL(_proxy_pda);

		#ifdef CONFIG_PARAVIRT
		/* Virtualized guests may want to use it */
		EXPORT_SYMBOL_GPL(cpu_gdt_descr);
		#endif

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