diff options
Diffstat (limited to 'arch/x86/kernel/nmi.c')
| -rw-r--r-- | arch/x86/kernel/nmi.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 18bc9b51ac9b..3755d0310026 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -21,13 +21,14 @@ #include <linux/ratelimit.h> #include <linux/slab.h> #include <linux/export.h> +#include <linux/atomic.h> #include <linux/sched/clock.h> #if defined(CONFIG_EDAC) #include <linux/edac.h> #endif -#include <linux/atomic.h> +#include <asm/cpu_entry_area.h> #include <asm/traps.h> #include <asm/mach_traps.h> #include <asm/nmi.h> @@ -487,6 +488,23 @@ static DEFINE_PER_CPU(unsigned long, nmi_cr2); * switch back to the original IDT. */ static DEFINE_PER_CPU(int, update_debug_stack); + +static bool notrace is_debug_stack(unsigned long addr) +{ + struct cea_exception_stacks *cs = __this_cpu_read(cea_exception_stacks); + unsigned long top = CEA_ESTACK_TOP(cs, DB); + unsigned long bot = CEA_ESTACK_BOT(cs, DB1); + + if (__this_cpu_read(debug_stack_usage)) + return true; + /* + * Note, this covers the guard page between DB and DB1 as well to + * avoid two checks. But by all means @addr can never point into + * the guard page. + */ + return addr >= bot && addr < top; +} +NOKPROBE_SYMBOL(is_debug_stack); #endif dotraplinkage notrace void |