diff --git a/arch/x86/include/asm/trampoline.h b/arch/x86/include/asm/trampoline.h index 780ba0ab94f9..90f06c25221d 100644 --- a/arch/x86/include/asm/trampoline.h +++ b/arch/x86/include/asm/trampoline.h @@ -13,6 +13,7 @@ extern unsigned char *trampoline_base; extern unsigned long init_rsp; extern unsigned long initial_code; +extern unsigned long initial_gs; #define TRAMPOLINE_SIZE roundup(trampoline_end - trampoline_data, PAGE_SIZE) #define TRAMPOLINE_BASE 0x6000 diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index 707c1f6f95fa..9ff67f8dc2c0 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -101,6 +101,7 @@ int acpi_save_state_mem(void) stack_start.sp = temp_stack + sizeof(temp_stack); early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(smp_processor_id()); + initial_gs = (unsigned long)cpu_pda(smp_processor_id()); #endif initial_code = (unsigned long)wakeup_long64; saved_magic = 0x123456789abcdef0; diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index bc2900ca82c7..76ffba2aa66d 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -26,8 +26,8 @@ #include #include -/* boot cpu pda */ -static struct x8664_pda _boot_cpu_pda; +/* boot cpu pda, referenced by head_64.S to initialize %gs for boot CPU */ +struct x8664_pda _boot_cpu_pda; #ifdef CONFIG_SMP /* diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 7ee0363871e8..2f0ab0089883 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -243,12 +243,15 @@ ENTRY(secondary_startup_64) movl %eax,%fs movl %eax,%gs - /* - * Setup up a dummy PDA. this is just for some early bootup code - * that does in_interrupt() - */ + /* Set up %gs. + * + * %gs should point to the pda. For initial boot, make %gs point + * to the _boot_cpu_pda in data section. For a secondary CPU, + * initial_gs should be set to its pda address before the CPU runs + * this code. + */ movl $MSR_GS_BASE,%ecx - movq $empty_zero_page,%rax + movq initial_gs(%rip),%rax movq %rax,%rdx shrq $32,%rdx wrmsr @@ -274,6 +277,8 @@ ENTRY(secondary_startup_64) .align 8 ENTRY(initial_code) .quad x86_64_start_kernel + ENTRY(initial_gs) + .quad _boot_cpu_pda __FINITDATA ENTRY(stack_start) diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 1a712da1dfa0..70d846628bbf 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -854,6 +854,7 @@ do_rest: #else cpu_pda(cpu)->pcurrent = c_idle.idle; clear_tsk_thread_flag(c_idle.idle, TIF_FORK); + initial_gs = (unsigned long)cpu_pda(cpu); #endif early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu); initial_code = (unsigned long)start_secondary;