Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar |
3 | * | |
4 | * This file contains the lowest level x86_64-specific interrupt | |
5 | * entry and irq statistics code. All the remaining irq logic is | |
6 | * done by the generic kernel/irq/ code and in the | |
7 | * x86_64-specific irq controller code. (e.g. i8259.c and | |
8 | * io_apic.c.) | |
9 | */ | |
10 | ||
11 | #include <linux/kernel_stat.h> | |
12 | #include <linux/interrupt.h> | |
13 | #include <linux/seq_file.h> | |
14 | #include <linux/module.h> | |
76e4f660 | 15 | #include <linux/delay.h> |
bcbc4f20 | 16 | #include <linux/ftrace.h> |
5f66b2a0 JSR |
17 | #include <linux/uaccess.h> |
18 | #include <linux/smp.h> | |
1da177e4 | 19 | #include <asm/io_apic.h> |
95833c83 | 20 | #include <asm/idle.h> |
3819cd48 | 21 | #include <asm/apic.h> |
1da177e4 | 22 | |
55af7796 MH |
23 | int sysctl_panic_on_stackoverflow; |
24 | ||
4961f10e ES |
25 | /* |
26 | * Probabilistic stack overflow check: | |
27 | * | |
28 | * Only check the stack in process context, because everything else | |
29 | * runs on the big interrupt stacks. Checking reliably is too expensive, | |
30 | * so we just check from interrupts. | |
31 | */ | |
32 | static inline void stack_overflow_check(struct pt_regs *regs) | |
33 | { | |
f377fa12 | 34 | #ifdef CONFIG_DEBUG_STACKOVERFLOW |
d2db6610 | 35 | #define STACK_TOP_MARGIN 128 |
37fe6a42 MH |
36 | struct orig_ist *oist; |
37 | u64 irq_stack_top, irq_stack_bottom; | |
38 | u64 estack_top, estack_bottom; | |
c9f4f06d | 39 | u64 curbase = (u64)task_stack_page(current); |
f377fa12 | 40 | |
f39b6f0e | 41 | if (user_mode(regs)) |
69682b62 MH |
42 | return; |
43 | ||
467e6b7a | 44 | if (regs->sp >= curbase + sizeof(struct thread_info) + |
d2db6610 | 45 | sizeof(struct pt_regs) + STACK_TOP_MARGIN && |
467e6b7a | 46 | regs->sp <= curbase + THREAD_SIZE) |
37fe6a42 MH |
47 | return; |
48 | ||
89cbc767 | 49 | irq_stack_top = (u64)this_cpu_ptr(irq_stack_union.irq_stack) + |
d2db6610 | 50 | STACK_TOP_MARGIN; |
89cbc767 | 51 | irq_stack_bottom = (u64)__this_cpu_read(irq_stack_ptr); |
37fe6a42 MH |
52 | if (regs->sp >= irq_stack_top && regs->sp <= irq_stack_bottom) |
53 | return; | |
54 | ||
89cbc767 | 55 | oist = this_cpu_ptr(&orig_ist); |
d2db6610 | 56 | estack_top = (u64)oist->ist[0] - EXCEPTION_STKSZ + STACK_TOP_MARGIN; |
37fe6a42 MH |
57 | estack_bottom = (u64)oist->ist[N_EXCEPTION_STACKS - 1]; |
58 | if (regs->sp >= estack_top && regs->sp <= estack_bottom) | |
59 | return; | |
f377fa12 | 60 | |
37fe6a42 MH |
61 | 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)\n", |
62 | current->comm, curbase, regs->sp, | |
63 | irq_stack_top, irq_stack_bottom, | |
64 | estack_top, estack_bottom); | |
55af7796 MH |
65 | |
66 | if (sysctl_panic_on_stackoverflow) | |
67 | panic("low stack detected by irq handler - check messages\n"); | |
4961f10e | 68 | #endif |
f377fa12 | 69 | } |
4961f10e | 70 | |
a782a7e4 | 71 | bool handle_irq(struct irq_desc *desc, struct pt_regs *regs) |
9b2b76a3 | 72 | { |
9b2b76a3 JF |
73 | stack_overflow_check(regs); |
74 | ||
a7e705af | 75 | if (IS_ERR_OR_NULL(desc)) |
9b2b76a3 JF |
76 | return false; |
77 | ||
bd0b9ac4 | 78 | generic_handle_irq_desc(desc); |
9b2b76a3 JF |
79 | return true; |
80 | } |