x86_64: fix the check point in stack_overflow_check
PATCH 1/1 x86_64: fix the check point in stack_overflow_check
stack_overflow_check() should consider the stack usage of pt_regs, and thus it could warn us in advance. Additionally, it looks a bit good that the warning time starts at INITIAL_JIFFIES.
Signed-off-by jia zhang <[email protected]>
---
Assume at the moment rsp get close to the check point before interrupt arrives. When interrupt really happens, thread_info will be partly overrode.
b/arch/x86/kernel/irq_64.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
arch/x86/kernel/irq_64.c +4 -3
@@ -29,11 +29,12 @@static inline void stack_overflow_check (struct pt_regs *regs) {u64 curbase = (u64 )task_stack_page (current); -static unsigned long warned =-60 *HZ ; +static unsigned long warned =INITIAL_JIFFIES -60 *HZ ;if (regs->sp >= curbase && regs->sp <= curbase +THREAD_SIZE && - regs->sp < curbase +sizeof (struct thread_info ) +128 && -time_after (jiffies, warned +60 *HZ )) { + regs->sp < curbase +sizeof (struct thread_info ) + +sizeof (struct pt_regs ) +128 && +time_after (jiffies, warned +60 *HZ )) {printk ("do_IRQ: %s near stack overflow (cur:%Lx,sp:%lx)\n" , current->comm, curbase, regs->sp);show_stack (NULL ,NULL );