From 947e76cdc34c782fc947313d4331380686eebbad Mon Sep 17 00:00:00 2001 From: Brian Gerst Date: Mon, 19 Jan 2009 12:21:28 +0900 Subject: x86: move stack_canary into irq_stack Impact: x86_64 percpu area layout change, irq_stack now at the beginning Now that the PDA is empty except for the stack canary, it can be removed. The irqstack is moved to the start of the per-cpu section. If the stack protector is enabled, the canary overlaps the bottom 48 bytes of the irqstack. tj: * updated subject * dropped asm relocation of irq_stack_ptr * updated comments a bit * rebased on top of stack canary changes Signed-off-by: Brian Gerst Signed-off-by: Tejun Heo --- arch/x86/kernel/cpu/common.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel/cpu/common.c') diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index f83a4d6160f..098934e72a1 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -881,12 +881,13 @@ __setup("clearcpuid=", setup_disablecpuid); #ifdef CONFIG_X86_64 struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table }; -DEFINE_PER_CPU_PAGE_ALIGNED(char[IRQ_STACK_SIZE], irq_stack); +DEFINE_PER_CPU_FIRST(union irq_stack_union, + irq_stack_union) __aligned(PAGE_SIZE); #ifdef CONFIG_SMP DEFINE_PER_CPU(char *, irq_stack_ptr); /* will be set during per cpu init */ #else DEFINE_PER_CPU(char *, irq_stack_ptr) = - per_cpu_var(irq_stack) + IRQ_STACK_SIZE - 64; + per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64; #endif DEFINE_PER_CPU(unsigned long, kernel_stack) = @@ -960,7 +961,7 @@ void __cpuinit cpu_init(void) loadsegment(fs, 0); loadsegment(gs, 0); - load_pda_offset(cpu); + load_gs_base(cpu); #ifdef CONFIG_NUMA if (cpu != 0 && percpu_read(node_number) == 0 && -- cgit v1.2.2