diff options
| -rw-r--r-- | arch/x86/kernel/irq_64.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index c0f89d136b80..f107eb2021f6 100644 --- a/arch/x86/kernel/irq_64.c +++ b/arch/x86/kernel/irq_64.c @@ -91,6 +91,35 @@ bool handle_irq(struct irq_desc *desc, struct pt_regs *regs) return true; } +#ifdef CONFIG_VMAP_STACK +/* + * VMAP the backing store with guard pages + */ +static int map_irq_stack(unsigned int cpu) +{ + char *stack = (char *)per_cpu_ptr(&irq_stack_backing_store, cpu); + struct page *pages[IRQ_STACK_SIZE / PAGE_SIZE]; + void *va; + int i; + + for (i = 0; i < IRQ_STACK_SIZE / PAGE_SIZE; i++) { + phys_addr_t pa = per_cpu_ptr_to_phys(stack + (i << PAGE_SHIFT)); + + pages[i] = pfn_to_page(pa >> PAGE_SHIFT); + } + + va = vmap(pages, IRQ_STACK_SIZE / PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL); + if (!va) + return -ENOMEM; + + per_cpu(hardirq_stack_ptr, cpu) = va + IRQ_STACK_SIZE; + return 0; +} +#else +/* + * If VMAP stacks are disabled due to KASAN, just use the per cpu + * backing store without guard pages. + */ static int map_irq_stack(unsigned int cpu) { void *va = per_cpu_ptr(&irq_stack_backing_store, cpu); @@ -98,6 +127,7 @@ static int map_irq_stack(unsigned int cpu) per_cpu(hardirq_stack_ptr, cpu) = va + IRQ_STACK_SIZE; return 0; } +#endif int irq_init_percpu_irqstack(unsigned int cpu) { |