diff options
Diffstat (limited to 'arch/x86/kernel/irq_64.c')
| -rw-r--r-- | arch/x86/kernel/irq_64.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index 0469cd078db1..b50ac9c7397b 100644 --- a/arch/x86/kernel/irq_64.c +++ b/arch/x86/kernel/irq_64.c @@ -26,9 +26,18 @@ int sysctl_panic_on_stackoverflow; /* * Probabilistic stack overflow check: * - * Only check the stack in process context, because everything else - * runs on the big interrupt stacks. Checking reliably is too expensive, - * so we just check from interrupts. + * Regular device interrupts can enter on the following stacks: + * + * - User stack + * + * - Kernel task stack + * + * - Interrupt stack if a device driver reenables interrupts + * which should only happen in really old drivers. + * + * - Debug IST stack + * + * All other contexts are invalid. */ static inline void stack_overflow_check(struct pt_regs *regs) { @@ -53,8 +62,8 @@ static inline void stack_overflow_check(struct pt_regs *regs) return; oist = this_cpu_ptr(&orig_ist); - estack_top = (u64)oist->ist[0] - EXCEPTION_STKSZ + STACK_TOP_MARGIN; - estack_bottom = (u64)oist->ist[N_EXCEPTION_STACKS - 1]; + estack_bottom = (u64)oist->ist[DEBUG_STACK]; + estack_top = estack_bottom - DEBUG_STKSZ + STACK_TOP_MARGIN; if (regs->sp >= estack_top && regs->sp <= estack_bottom) return; |