90 lines
2.4 KiB
C
90 lines
2.4 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
|
/*
|
||
|
|
* Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
|
||
|
|
*
|
||
|
|
* This file contains the lowest level x86_64-specific interrupt
|
||
|
|
* entry and irq statistics code. All the remaining irq logic is
|
||
|
|
* done by the generic kernel/irq/ code and in the
|
||
|
|
* x86_64-specific irq controller code. (e.g. i8259.c and
|
||
|
|
* io_apic.c.)
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/kernel_stat.h>
|
||
|
|
#include <linux/interrupt.h>
|
||
|
|
#include <linux/irq.h>
|
||
|
|
#include <linux/seq_file.h>
|
||
|
|
#include <linux/delay.h>
|
||
|
|
#include <linux/ftrace.h>
|
||
|
|
#include <linux/uaccess.h>
|
||
|
|
#include <linux/smp.h>
|
||
|
|
#include <linux/sched/task_stack.h>
|
||
|
|
#include <asm/io_apic.h>
|
||
|
|
#include <asm/apic.h>
|
||
|
|
|
||
|
|
int sysctl_panic_on_stackoverflow;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Probabilistic stack overflow check:
|
||
|
|
*
|
||
|
|
* 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)
|
||
|
|
{
|
||
|
|
#ifdef CONFIG_DEBUG_STACKOVERFLOW
|
||
|
|
#define STACK_TOP_MARGIN 128
|
||
|
|
struct orig_ist *oist;
|
||
|
|
u64 irq_stack_top, irq_stack_bottom;
|
||
|
|
u64 estack_top, estack_bottom;
|
||
|
|
u64 curbase = (u64)task_stack_page(current);
|
||
|
|
|
||
|
|
if (user_mode(regs))
|
||
|
|
return;
|
||
|
|
|
||
|
|
if (regs->sp >= curbase + sizeof(struct pt_regs) + STACK_TOP_MARGIN &&
|
||
|
|
regs->sp <= curbase + THREAD_SIZE)
|
||
|
|
return;
|
||
|
|
|
||
|
|
irq_stack_top = (u64)this_cpu_ptr(irq_stack_union.irq_stack) +
|
||
|
|
STACK_TOP_MARGIN;
|
||
|
|
irq_stack_bottom = (u64)__this_cpu_read(irq_stack_ptr);
|
||
|
|
if (regs->sp >= irq_stack_top && regs->sp <= irq_stack_bottom)
|
||
|
|
return;
|
||
|
|
|
||
|
|
oist = this_cpu_ptr(&orig_ist);
|
||
|
|
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;
|
||
|
|
|
||
|
|
WARN_ONCE(1, "do_IRQ(): %s has overflown the kernel stack (cur:%Lx,sp:%lx,irq stk top-bottom:%Lx-%Lx,exception stk top-bottom:%Lx-%Lx,ip:%pF)\n",
|
||
|
|
current->comm, curbase, regs->sp,
|
||
|
|
irq_stack_top, irq_stack_bottom,
|
||
|
|
estack_top, estack_bottom, (void *)regs->ip);
|
||
|
|
|
||
|
|
if (sysctl_panic_on_stackoverflow)
|
||
|
|
panic("low stack detected by irq handler - check messages\n");
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
bool handle_irq(struct irq_desc *desc, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
stack_overflow_check(regs);
|
||
|
|
|
||
|
|
if (IS_ERR_OR_NULL(desc))
|
||
|
|
return false;
|
||
|
|
|
||
|
|
generic_handle_irq_desc(desc);
|
||
|
|
return true;
|
||
|
|
}
|