On 2021/9/16 下午6:02, Peter Zijlstra wrote:
[snip]
>
> +static __always_inline bool in_stack_guard(void *addr, void *begin, void *end)
> +{
> +#ifdef CONFIG_VMAP_STACK
> + if (addr > (begin - PAGE_SIZE))
> + return true;
After fix this logical as:
addr >= (begin - PAGE_SIZE) && addr < begin
it's working.
Regards,
Michael Wang
> +#endif
> + return false;
> +}
[snip]
>
> #ifdef CONFIG_X86_ESPFIX64
> @@ -455,9 +456,11 @@ DEFINE_IDTENTRY_DF(exc_double_fault)
> * stack even if the actual trigger for the double fault was
> * something else.
> */
> - if ((unsigned long)task_stack_page(tsk) - 1 - address < PAGE_SIZE) {
> - handle_stack_overflow("kernel stack overflow (double-fault)",
> - regs, address);
> + if (get_stack_info_noinstr((void *)address, current, &info) &&
> + info.type & STACK_TYPE_GUARD) {
> + const char *name = stack_type_name(info.type & ~STACK_TYPE_GUARD);
> + pr_emerg("BUG: %s stack guard hit at %p (stack is %p..%p)\n",
> + name, (void *)address, info.begin, info.end);
> }
> #endif
>
> @@ -708,7 +711,9 @@ asmlinkage __visible noinstr struct pt_regs *vc_switch_off_ist(struct pt_regs *r
> sp = regs->sp;
> stack = (unsigned long *)sp;
>
> - if (!get_stack_info_noinstr(stack, current, &info) || info.type == STACK_TYPE_ENTRY ||
> + if (!get_stack_info_noinstr(stack, current, &info) ||
> + info.type & STACK_TYPE_GUARD ||
> + info.type == STACK_TYPE_ENTRY ||
> info.type >= STACK_TYPE_EXCEPTION_LAST)
> sp = __this_cpu_ist_top_va(VC2);
>
>
