Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * Copyright (C) 1991, 1992 Linus Torvalds |
Alexander van Heukelum | a8c1be9 | 2008-07-02 01:29:44 +0200 | [diff] [blame] | 3 | * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * |
| 5 | * Pentium III FXSR, SSE support |
| 6 | * Gareth Hughes <gareth@valinux.com>, May 2000 |
| 7 | */ |
| 8 | |
| 9 | /* |
Alexander van Heukelum | c1d518c | 2008-10-03 23:17:11 +0200 | [diff] [blame] | 10 | * Handle hardware traps and faults. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | */ |
Joe Perches | c767a54 | 2012-05-21 19:50:07 -0700 | [diff] [blame] | 12 | |
| 13 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 14 | |
Frederic Weisbecker | 56dd947 | 2013-02-24 00:23:25 +0100 | [diff] [blame^] | 15 | #include <linux/context_tracking.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/interrupt.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | #include <linux/kallsyms.h> |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 18 | #include <linux/spinlock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <linux/kprobes.h> |
Andrew Morton | 1e2af92 | 2006-09-27 01:51:15 -0700 | [diff] [blame] | 20 | #include <linux/uaccess.h> |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 21 | #include <linux/kdebug.h> |
Jason Wessel | f503b5a | 2010-05-20 21:04:25 -0500 | [diff] [blame] | 22 | #include <linux/kgdb.h> |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 23 | #include <linux/kernel.h> |
| 24 | #include <linux/module.h> |
| 25 | #include <linux/ptrace.h> |
| 26 | #include <linux/string.h> |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 27 | #include <linux/delay.h> |
| 28 | #include <linux/errno.h> |
| 29 | #include <linux/kexec.h> |
| 30 | #include <linux/sched.h> |
| 31 | #include <linux/timer.h> |
| 32 | #include <linux/init.h> |
Jeremy Fitzhardinge | 91768d6 | 2006-12-08 02:36:21 -0800 | [diff] [blame] | 33 | #include <linux/bug.h> |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 34 | #include <linux/nmi.h> |
| 35 | #include <linux/mm.h> |
Alexander van Heukelum | c1d518c | 2008-10-03 23:17:11 +0200 | [diff] [blame] | 36 | #include <linux/smp.h> |
| 37 | #include <linux/io.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | |
| 39 | #ifdef CONFIG_EISA |
| 40 | #include <linux/ioport.h> |
| 41 | #include <linux/eisa.h> |
| 42 | #endif |
| 43 | |
Dave Jiang | c0d1217 | 2007-07-19 01:49:46 -0700 | [diff] [blame] | 44 | #if defined(CONFIG_EDAC) |
| 45 | #include <linux/edac.h> |
| 46 | #endif |
| 47 | |
Vegard Nossum | f856129 | 2008-04-04 00:53:23 +0200 | [diff] [blame] | 48 | #include <asm/kmemcheck.h> |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 49 | #include <asm/stacktrace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | #include <asm/processor.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | #include <asm/debugreg.h> |
Arun Sharma | 60063497 | 2011-07-26 16:09:06 -0700 | [diff] [blame] | 52 | #include <linux/atomic.h> |
Steven Rostedt | 08d636b | 2011-08-16 09:57:10 -0400 | [diff] [blame] | 53 | #include <asm/ftrace.h> |
Alexander van Heukelum | c1d518c | 2008-10-03 23:17:11 +0200 | [diff] [blame] | 54 | #include <asm/traps.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | #include <asm/desc.h> |
| 56 | #include <asm/i387.h> |
Linus Torvalds | 1361b83 | 2012-02-21 13:19:22 -0800 | [diff] [blame] | 57 | #include <asm/fpu-internal.h> |
Hidetoshi Seto | 9e55e44 | 2009-06-15 17:22:15 +0900 | [diff] [blame] | 58 | #include <asm/mce.h> |
Ingo Molnar | 1164dd0 | 2009-01-28 19:34:09 +0100 | [diff] [blame] | 59 | #include <asm/mach_traps.h> |
Alexander van Heukelum | c1d518c | 2008-10-03 23:17:11 +0200 | [diff] [blame] | 60 | |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 61 | #ifdef CONFIG_X86_64 |
Thomas Gleixner | 428cf90 | 2009-08-20 10:35:46 +0200 | [diff] [blame] | 62 | #include <asm/x86_init.h> |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 63 | #include <asm/pgalloc.h> |
| 64 | #include <asm/proto.h> |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 65 | #else |
Alexander van Heukelum | c1d518c | 2008-10-03 23:17:11 +0200 | [diff] [blame] | 66 | #include <asm/processor-flags.h> |
Ingo Molnar | 8e6dafd | 2009-02-23 00:34:39 +0100 | [diff] [blame] | 67 | #include <asm/setup.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | asmlinkage int system_call(void); |
| 70 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | /* |
| 72 | * The IDT has to be page-aligned to simplify the Pentium |
Tim Abbott | 07e81d6 | 2009-09-16 16:44:29 -0400 | [diff] [blame] | 73 | * F0 0F bug workaround. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | */ |
Tim Abbott | 07e81d6 | 2009-09-16 16:44:29 -0400 | [diff] [blame] | 75 | gate_desc idt_table[NR_VECTORS] __page_aligned_data = { { { { 0, 0 } } }, }; |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 76 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | |
Yinghai Lu | b77b881 | 2008-12-19 15:23:44 -0800 | [diff] [blame] | 78 | DECLARE_BITMAP(used_vectors, NR_VECTORS); |
| 79 | EXPORT_SYMBOL_GPL(used_vectors); |
| 80 | |
Alexander van Heukelum | 762db43 | 2008-09-09 21:55:55 +0200 | [diff] [blame] | 81 | static inline void conditional_sti(struct pt_regs *regs) |
| 82 | { |
| 83 | if (regs->flags & X86_EFLAGS_IF) |
| 84 | local_irq_enable(); |
| 85 | } |
| 86 | |
Alexander van Heukelum | 3d2a71a | 2008-09-30 18:41:37 +0200 | [diff] [blame] | 87 | static inline void preempt_conditional_sti(struct pt_regs *regs) |
| 88 | { |
| 89 | inc_preempt_count(); |
| 90 | if (regs->flags & X86_EFLAGS_IF) |
| 91 | local_irq_enable(); |
| 92 | } |
| 93 | |
Thomas Gleixner | be71661 | 2009-01-13 23:36:34 +0100 | [diff] [blame] | 94 | static inline void conditional_cli(struct pt_regs *regs) |
| 95 | { |
| 96 | if (regs->flags & X86_EFLAGS_IF) |
| 97 | local_irq_disable(); |
| 98 | } |
| 99 | |
Alexander van Heukelum | 3d2a71a | 2008-09-30 18:41:37 +0200 | [diff] [blame] | 100 | static inline void preempt_conditional_cli(struct pt_regs *regs) |
| 101 | { |
| 102 | if (regs->flags & X86_EFLAGS_IF) |
| 103 | local_irq_disable(); |
| 104 | dec_preempt_count(); |
| 105 | } |
| 106 | |
Frederic Weisbecker | c416ddf | 2012-09-25 14:51:19 +0200 | [diff] [blame] | 107 | static int __kprobes |
| 108 | do_trap_no_signal(struct task_struct *tsk, int trapnr, char *str, |
| 109 | struct pt_regs *regs, long error_code) |
| 110 | { |
| 111 | #ifdef CONFIG_X86_32 |
| 112 | if (regs->flags & X86_VM_MASK) { |
| 113 | /* |
| 114 | * Traps 0, 1, 3, 4, and 5 should be forwarded to vm86. |
| 115 | * On nmi (interrupt 2), do_trap should not be called. |
| 116 | */ |
| 117 | if (trapnr < X86_TRAP_UD) { |
| 118 | if (!handle_vm86_trap((struct kernel_vm86_regs *) regs, |
| 119 | error_code, trapnr)) |
| 120 | return 0; |
| 121 | } |
| 122 | return -1; |
| 123 | } |
| 124 | #endif |
| 125 | if (!user_mode(regs)) { |
| 126 | if (!fixup_exception(regs)) { |
| 127 | tsk->thread.error_code = error_code; |
| 128 | tsk->thread.trap_nr = trapnr; |
| 129 | die(str, regs, error_code); |
| 130 | } |
| 131 | return 0; |
| 132 | } |
| 133 | |
| 134 | return -1; |
| 135 | } |
| 136 | |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 137 | static void __kprobes |
Alexander van Heukelum | 3c1326f | 2008-09-26 14:03:08 +0200 | [diff] [blame] | 138 | do_trap(int trapnr, int signr, char *str, struct pt_regs *regs, |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 139 | long error_code, siginfo_t *info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | { |
Alexander Nyberg | 4f339ec | 2005-06-25 14:58:27 -0700 | [diff] [blame] | 141 | struct task_struct *tsk = current; |
Alexander Nyberg | 4f339ec | 2005-06-25 14:58:27 -0700 | [diff] [blame] | 142 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | |
Frederic Weisbecker | c416ddf | 2012-09-25 14:51:19 +0200 | [diff] [blame] | 144 | if (!do_trap_no_signal(tsk, trapnr, str, regs, error_code)) |
| 145 | return; |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 146 | /* |
Srikar Dronamraju | 51e7dc7 | 2012-03-12 14:55:55 +0530 | [diff] [blame] | 147 | * We want error_code and trap_nr set for userspace faults and |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 148 | * kernelspace faults which result in die(), but not |
| 149 | * kernelspace faults which are fixed up. die() gives the |
| 150 | * process no chance to handle the signal and notice the |
| 151 | * kernel fault information, so that won't result in polluting |
| 152 | * the information about previously queued, but not yet |
| 153 | * delivered, faults. See also do_general_protection below. |
| 154 | */ |
| 155 | tsk->thread.error_code = error_code; |
Srikar Dronamraju | 51e7dc7 | 2012-03-12 14:55:55 +0530 | [diff] [blame] | 156 | tsk->thread.trap_nr = trapnr; |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 157 | |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 158 | #ifdef CONFIG_X86_64 |
| 159 | if (show_unhandled_signals && unhandled_signal(tsk, signr) && |
| 160 | printk_ratelimit()) { |
Joe Perches | c767a54 | 2012-05-21 19:50:07 -0700 | [diff] [blame] | 161 | pr_info("%s[%d] trap %s ip:%lx sp:%lx error:%lx", |
| 162 | tsk->comm, tsk->pid, str, |
| 163 | regs->ip, regs->sp, error_code); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 164 | print_vma_addr(" in ", regs->ip); |
Joe Perches | c767a54 | 2012-05-21 19:50:07 -0700 | [diff] [blame] | 165 | pr_cont("\n"); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 166 | } |
| 167 | #endif |
| 168 | |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 169 | if (info) |
| 170 | force_sig_info(signr, info, tsk); |
| 171 | else |
| 172 | force_sig(signr, tsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | } |
| 174 | |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 175 | #define DO_ERROR(trapnr, signr, str, name) \ |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 176 | dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \ |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 177 | { \ |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 178 | exception_enter(regs); \ |
| 179 | if (notify_die(DIE_TRAP, str, regs, error_code, \ |
| 180 | trapnr, signr) == NOTIFY_STOP) { \ |
| 181 | exception_exit(regs); \ |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 182 | return; \ |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 183 | } \ |
Alexander van Heukelum | 61aef7d | 2008-09-09 21:55:56 +0200 | [diff] [blame] | 184 | conditional_sti(regs); \ |
Alexander van Heukelum | 3c1326f | 2008-09-26 14:03:08 +0200 | [diff] [blame] | 185 | do_trap(trapnr, signr, str, regs, error_code, NULL); \ |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 186 | exception_exit(regs); \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | } |
| 188 | |
Alexander van Heukelum | 3c1326f | 2008-09-26 14:03:08 +0200 | [diff] [blame] | 189 | #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 190 | dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \ |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 191 | { \ |
| 192 | siginfo_t info; \ |
| 193 | info.si_signo = signr; \ |
| 194 | info.si_errno = 0; \ |
| 195 | info.si_code = sicode; \ |
| 196 | info.si_addr = (void __user *)siaddr; \ |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 197 | exception_enter(regs); \ |
| 198 | if (notify_die(DIE_TRAP, str, regs, error_code, \ |
| 199 | trapnr, signr) == NOTIFY_STOP) { \ |
| 200 | exception_exit(regs); \ |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 201 | return; \ |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 202 | } \ |
Alexander van Heukelum | 61aef7d | 2008-09-09 21:55:56 +0200 | [diff] [blame] | 203 | conditional_sti(regs); \ |
Alexander van Heukelum | 3c1326f | 2008-09-26 14:03:08 +0200 | [diff] [blame] | 204 | do_trap(trapnr, signr, str, regs, error_code, &info); \ |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 205 | exception_exit(regs); \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | } |
| 207 | |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 208 | DO_ERROR_INFO(X86_TRAP_DE, SIGFPE, "divide error", divide_error, FPE_INTDIV, |
| 209 | regs->ip) |
| 210 | DO_ERROR(X86_TRAP_OF, SIGSEGV, "overflow", overflow) |
| 211 | DO_ERROR(X86_TRAP_BR, SIGSEGV, "bounds", bounds) |
| 212 | DO_ERROR_INFO(X86_TRAP_UD, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, |
| 213 | regs->ip) |
| 214 | DO_ERROR(X86_TRAP_OLD_MF, SIGFPE, "coprocessor segment overrun", |
| 215 | coprocessor_segment_overrun) |
| 216 | DO_ERROR(X86_TRAP_TS, SIGSEGV, "invalid TSS", invalid_TSS) |
| 217 | DO_ERROR(X86_TRAP_NP, SIGBUS, "segment not present", segment_not_present) |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 218 | #ifdef CONFIG_X86_32 |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 219 | DO_ERROR(X86_TRAP_SS, SIGBUS, "stack segment", stack_segment) |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 220 | #endif |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 221 | DO_ERROR_INFO(X86_TRAP_AC, SIGBUS, "alignment check", alignment_check, |
| 222 | BUS_ADRALN, 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 224 | #ifdef CONFIG_X86_64 |
| 225 | /* Runs on IST stack */ |
| 226 | dotraplinkage void do_stack_segment(struct pt_regs *regs, long error_code) |
| 227 | { |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 228 | exception_enter(regs); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 229 | if (notify_die(DIE_TRAP, "stack segment", regs, error_code, |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 230 | X86_TRAP_SS, SIGBUS) != NOTIFY_STOP) { |
| 231 | preempt_conditional_sti(regs); |
| 232 | do_trap(X86_TRAP_SS, SIGBUS, "stack segment", regs, error_code, NULL); |
| 233 | preempt_conditional_cli(regs); |
| 234 | } |
| 235 | exception_exit(regs); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 236 | } |
| 237 | |
| 238 | dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) |
| 239 | { |
| 240 | static const char str[] = "double fault"; |
| 241 | struct task_struct *tsk = current; |
| 242 | |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 243 | exception_enter(regs); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 244 | /* Return not checked because double check cannot be ignored */ |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 245 | notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 246 | |
| 247 | tsk->thread.error_code = error_code; |
Srikar Dronamraju | 51e7dc7 | 2012-03-12 14:55:55 +0530 | [diff] [blame] | 248 | tsk->thread.trap_nr = X86_TRAP_DF; |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 249 | |
Ingo Molnar | bd8b96d | 2008-12-26 09:20:22 +0100 | [diff] [blame] | 250 | /* |
| 251 | * This is always a kernel trap and never fixable (and thus must |
| 252 | * never return). |
| 253 | */ |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 254 | for (;;) |
| 255 | die(str, regs, error_code); |
| 256 | } |
| 257 | #endif |
| 258 | |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 259 | dotraplinkage void __kprobes |
Alexander van Heukelum | 13485ab | 2008-07-02 01:32:04 +0200 | [diff] [blame] | 260 | do_general_protection(struct pt_regs *regs, long error_code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | { |
Alexander van Heukelum | 13485ab | 2008-07-02 01:32:04 +0200 | [diff] [blame] | 262 | struct task_struct *tsk; |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 263 | |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 264 | exception_enter(regs); |
Alexander van Heukelum | c6df0d7 | 2008-09-09 21:56:07 +0200 | [diff] [blame] | 265 | conditional_sti(regs); |
| 266 | |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 267 | #ifdef CONFIG_X86_32 |
Frederic Weisbecker | ef3f628 | 2012-09-24 21:05:52 +0200 | [diff] [blame] | 268 | if (regs->flags & X86_VM_MASK) { |
| 269 | local_irq_enable(); |
| 270 | handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code); |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 271 | goto exit; |
Frederic Weisbecker | ef3f628 | 2012-09-24 21:05:52 +0200 | [diff] [blame] | 272 | } |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 273 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | |
Alexander van Heukelum | 13485ab | 2008-07-02 01:32:04 +0200 | [diff] [blame] | 275 | tsk = current; |
Frederic Weisbecker | ef3f628 | 2012-09-24 21:05:52 +0200 | [diff] [blame] | 276 | if (!user_mode(regs)) { |
| 277 | if (fixup_exception(regs)) |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 278 | goto exit; |
Frederic Weisbecker | ef3f628 | 2012-09-24 21:05:52 +0200 | [diff] [blame] | 279 | |
| 280 | tsk->thread.error_code = error_code; |
| 281 | tsk->thread.trap_nr = X86_TRAP_GP; |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 282 | if (notify_die(DIE_GPF, "general protection fault", regs, error_code, |
| 283 | X86_TRAP_GP, SIGSEGV) != NOTIFY_STOP) |
Frederic Weisbecker | ef3f628 | 2012-09-24 21:05:52 +0200 | [diff] [blame] | 284 | die("general protection fault", regs, error_code); |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 285 | goto exit; |
Frederic Weisbecker | ef3f628 | 2012-09-24 21:05:52 +0200 | [diff] [blame] | 286 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 287 | |
Alexander van Heukelum | 13485ab | 2008-07-02 01:32:04 +0200 | [diff] [blame] | 288 | tsk->thread.error_code = error_code; |
Srikar Dronamraju | 51e7dc7 | 2012-03-12 14:55:55 +0530 | [diff] [blame] | 289 | tsk->thread.trap_nr = X86_TRAP_GP; |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 290 | |
Alexander van Heukelum | 13485ab | 2008-07-02 01:32:04 +0200 | [diff] [blame] | 291 | if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) && |
| 292 | printk_ratelimit()) { |
Joe Perches | c767a54 | 2012-05-21 19:50:07 -0700 | [diff] [blame] | 293 | pr_info("%s[%d] general protection ip:%lx sp:%lx error:%lx", |
Alexander van Heukelum | 13485ab | 2008-07-02 01:32:04 +0200 | [diff] [blame] | 294 | tsk->comm, task_pid_nr(tsk), |
| 295 | regs->ip, regs->sp, error_code); |
Andi Kleen | 0325291 | 2008-01-30 13:33:18 +0100 | [diff] [blame] | 296 | print_vma_addr(" in ", regs->ip); |
Joe Perches | c767a54 | 2012-05-21 19:50:07 -0700 | [diff] [blame] | 297 | pr_cont("\n"); |
Andi Kleen | 0325291 | 2008-01-30 13:33:18 +0100 | [diff] [blame] | 298 | } |
Masoud Asgharifard Sharbiani | abd4f75 | 2007-07-22 11:12:28 +0200 | [diff] [blame] | 299 | |
Alexander van Heukelum | 13485ab | 2008-07-02 01:32:04 +0200 | [diff] [blame] | 300 | force_sig(SIGSEGV, tsk); |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 301 | exit: |
| 302 | exception_exit(regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | } |
| 304 | |
Alexander van Heukelum | c1d518c | 2008-10-03 23:17:11 +0200 | [diff] [blame] | 305 | /* May run on IST stack. */ |
Steven Rostedt | 08d636b | 2011-08-16 09:57:10 -0400 | [diff] [blame] | 306 | dotraplinkage void __kprobes notrace do_int3(struct pt_regs *regs, long error_code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | { |
Steven Rostedt | 08d636b | 2011-08-16 09:57:10 -0400 | [diff] [blame] | 308 | #ifdef CONFIG_DYNAMIC_FTRACE |
Steven Rostedt | a192cd0 | 2012-05-30 13:26:37 -0400 | [diff] [blame] | 309 | /* |
| 310 | * ftrace must be first, everything else may cause a recursive crash. |
| 311 | * See note by declaration of modifying_ftrace_code in ftrace.c |
| 312 | */ |
| 313 | if (unlikely(atomic_read(&modifying_ftrace_code)) && |
| 314 | ftrace_int3_handler(regs)) |
Steven Rostedt | 08d636b | 2011-08-16 09:57:10 -0400 | [diff] [blame] | 315 | return; |
| 316 | #endif |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 317 | exception_enter(regs); |
Jason Wessel | f503b5a | 2010-05-20 21:04:25 -0500 | [diff] [blame] | 318 | #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 319 | if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP, |
| 320 | SIGTRAP) == NOTIFY_STOP) |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 321 | goto exit; |
Jason Wessel | f503b5a | 2010-05-20 21:04:25 -0500 | [diff] [blame] | 322 | #endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */ |
Srikar Dronamraju | cc3a1bf | 2011-10-25 19:51:59 +0530 | [diff] [blame] | 323 | |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 324 | if (notify_die(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP, |
| 325 | SIGTRAP) == NOTIFY_STOP) |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 326 | goto exit; |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 327 | |
Steven Rostedt | 4218118 | 2011-12-16 11:43:02 -0500 | [diff] [blame] | 328 | /* |
| 329 | * Let others (NMI) know that the debug stack is in use |
| 330 | * as we may switch to the interrupt stack. |
| 331 | */ |
| 332 | debug_stack_usage_inc(); |
Alexander van Heukelum | 4915a35 | 2008-10-03 22:00:34 +0200 | [diff] [blame] | 333 | preempt_conditional_sti(regs); |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 334 | do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, NULL); |
Alexander van Heukelum | 4915a35 | 2008-10-03 22:00:34 +0200 | [diff] [blame] | 335 | preempt_conditional_cli(regs); |
Steven Rostedt | 4218118 | 2011-12-16 11:43:02 -0500 | [diff] [blame] | 336 | debug_stack_usage_dec(); |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 337 | exit: |
| 338 | exception_exit(regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 341 | #ifdef CONFIG_X86_64 |
Ingo Molnar | bd8b96d | 2008-12-26 09:20:22 +0100 | [diff] [blame] | 342 | /* |
| 343 | * Help handler running on IST stack to switch back to user stack |
| 344 | * for scheduling or signal handling. The actual stack switch is done in |
| 345 | * entry.S |
| 346 | */ |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 347 | asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) |
| 348 | { |
| 349 | struct pt_regs *regs = eregs; |
| 350 | /* Did already sync */ |
| 351 | if (eregs == (struct pt_regs *)eregs->sp) |
| 352 | ; |
| 353 | /* Exception from user space */ |
| 354 | else if (user_mode(eregs)) |
| 355 | regs = task_pt_regs(current); |
Ingo Molnar | bd8b96d | 2008-12-26 09:20:22 +0100 | [diff] [blame] | 356 | /* |
| 357 | * Exception from kernel and interrupts are enabled. Move to |
| 358 | * kernel process stack. |
| 359 | */ |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 360 | else if (eregs->flags & X86_EFLAGS_IF) |
| 361 | regs = (struct pt_regs *)(eregs->sp -= sizeof(struct pt_regs)); |
| 362 | if (eregs != regs) |
| 363 | *regs = *eregs; |
| 364 | return regs; |
| 365 | } |
| 366 | #endif |
| 367 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | /* |
| 369 | * Our handling of the processor debug registers is non-trivial. |
| 370 | * We do not clear them on entry and exit from the kernel. Therefore |
| 371 | * it is possible to get a watchpoint trap here from inside the kernel. |
| 372 | * However, the code in ./ptrace.c has ensured that the user can |
| 373 | * only set watchpoints on userspace addresses. Therefore the in-kernel |
| 374 | * watchpoint trap can only occur in code which is reading/writing |
| 375 | * from user space. Such code must not hold kernel locks (since it |
| 376 | * can equally take a page fault), therefore it is safe to call |
| 377 | * force_sig_info even though that claims and releases locks. |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 378 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | * Code in ./signal.c ensures that the debug control register |
| 380 | * is restored before we deliver any signal, and therefore that |
| 381 | * user code runs with the correct debug control register even though |
| 382 | * we clear it here. |
| 383 | * |
| 384 | * Being careful here means that we don't have to be as careful in a |
| 385 | * lot of more complicated places (task switching can be a bit lazy |
| 386 | * about restoring all the debug state, and ptrace doesn't have to |
| 387 | * find every occurrence of the TF bit that could be saved away even |
| 388 | * by user code) |
Alexander van Heukelum | c1d518c | 2008-10-03 23:17:11 +0200 | [diff] [blame] | 389 | * |
| 390 | * May run on IST stack. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | */ |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 392 | dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | struct task_struct *tsk = current; |
Frederic Weisbecker | a1e80fa | 2010-06-30 15:09:06 +0200 | [diff] [blame] | 395 | int user_icebp = 0; |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 396 | unsigned long dr6; |
Srinivasa Ds | da654b7 | 2008-09-23 15:23:52 +0530 | [diff] [blame] | 397 | int si_code; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 398 | |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 399 | exception_enter(regs); |
| 400 | |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 401 | get_debugreg(dr6, 6); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | |
K.Prasad | 40f9249 | 2010-01-28 16:44:01 +0530 | [diff] [blame] | 403 | /* Filter out all the reserved bits which are preset to 1 */ |
| 404 | dr6 &= ~DR6_RESERVED; |
| 405 | |
Frederic Weisbecker | a1e80fa | 2010-06-30 15:09:06 +0200 | [diff] [blame] | 406 | /* |
| 407 | * If dr6 has no reason to give us about the origin of this trap, |
| 408 | * then it's very likely the result of an icebp/int01 trap. |
| 409 | * User wants a sigtrap for that. |
| 410 | */ |
| 411 | if (!dr6 && user_mode(regs)) |
| 412 | user_icebp = 1; |
| 413 | |
Vegard Nossum | f856129 | 2008-04-04 00:53:23 +0200 | [diff] [blame] | 414 | /* Catch kmemcheck conditions first of all! */ |
Ingo Molnar | eadb8a0 | 2009-06-17 12:52:15 +0200 | [diff] [blame] | 415 | if ((dr6 & DR_STEP) && kmemcheck_trap(regs)) |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 416 | goto exit; |
Vegard Nossum | f856129 | 2008-04-04 00:53:23 +0200 | [diff] [blame] | 417 | |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 418 | /* DR6 may or may not be cleared by the CPU */ |
| 419 | set_debugreg(0, 6); |
Roland McGrath | 10faa81 | 2008-01-30 13:30:54 +0100 | [diff] [blame] | 420 | |
Peter Zijlstra | ea8e61b | 2010-03-25 14:51:51 +0100 | [diff] [blame] | 421 | /* |
| 422 | * The processor cleared BTF, so don't mark that we need it set. |
| 423 | */ |
| 424 | clear_tsk_thread_flag(tsk, TIF_BLOCKSTEP); |
| 425 | |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 426 | /* Store the virtualized DR6 value */ |
| 427 | tsk->thread.debugreg6 = dr6; |
| 428 | |
K.Prasad | 62edab9 | 2009-06-01 23:47:06 +0530 | [diff] [blame] | 429 | if (notify_die(DIE_DEBUG, "debug", regs, PTR_ERR(&dr6), error_code, |
| 430 | SIGTRAP) == NOTIFY_STOP) |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 431 | goto exit; |
Alexander van Heukelum | 3d2a71a | 2008-09-30 18:41:37 +0200 | [diff] [blame] | 432 | |
Steven Rostedt | 4218118 | 2011-12-16 11:43:02 -0500 | [diff] [blame] | 433 | /* |
| 434 | * Let others (NMI) know that the debug stack is in use |
| 435 | * as we may switch to the interrupt stack. |
| 436 | */ |
| 437 | debug_stack_usage_inc(); |
| 438 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | /* It's safe to allow irq's after DR6 has been saved */ |
Alexander van Heukelum | 3d2a71a | 2008-09-30 18:41:37 +0200 | [diff] [blame] | 440 | preempt_conditional_sti(regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 441 | |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 442 | if (regs->flags & X86_VM_MASK) { |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 443 | handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, |
| 444 | X86_TRAP_DB); |
Bart Oldeman | 6554287 | 2010-09-23 13:16:58 -0400 | [diff] [blame] | 445 | preempt_conditional_cli(regs); |
Steven Rostedt | 4218118 | 2011-12-16 11:43:02 -0500 | [diff] [blame] | 446 | debug_stack_usage_dec(); |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 447 | goto exit; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | } |
| 449 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 450 | /* |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 451 | * Single-stepping through system calls: ignore any exceptions in |
| 452 | * kernel space, but re-enable TF when returning to user mode. |
| 453 | * |
| 454 | * We already checked v86 mode above, so we can check for kernel mode |
| 455 | * by just checking the CPL of CS. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 456 | */ |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 457 | if ((dr6 & DR_STEP) && !user_mode(regs)) { |
| 458 | tsk->thread.debugreg6 &= ~DR_STEP; |
| 459 | set_tsk_thread_flag(tsk, TIF_SINGLESTEP); |
| 460 | regs->flags &= ~X86_EFLAGS_TF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | } |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 462 | si_code = get_si_code(tsk->thread.debugreg6); |
Frederic Weisbecker | a1e80fa | 2010-06-30 15:09:06 +0200 | [diff] [blame] | 463 | if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS) || user_icebp) |
K.Prasad | 08d6832 | 2009-06-01 23:44:08 +0530 | [diff] [blame] | 464 | send_sigtrap(tsk, regs, error_code, si_code); |
Alexander van Heukelum | 3d2a71a | 2008-09-30 18:41:37 +0200 | [diff] [blame] | 465 | preempt_conditional_cli(regs); |
Steven Rostedt | 4218118 | 2011-12-16 11:43:02 -0500 | [diff] [blame] | 466 | debug_stack_usage_dec(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 468 | exit: |
| 469 | exception_exit(regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | } |
| 471 | |
| 472 | /* |
| 473 | * Note that we play around with the 'TS' bit in an attempt to get |
| 474 | * the correct behaviour even in the presence of the asynchronous |
| 475 | * IRQ13 behaviour |
| 476 | */ |
Brian Gerst | 9b6dba9 | 2010-03-21 09:00:44 -0400 | [diff] [blame] | 477 | void math_error(struct pt_regs *regs, int error_code, int trapnr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | { |
Brian Gerst | e2e75c9 | 2010-03-21 09:00:45 -0400 | [diff] [blame] | 479 | struct task_struct *task = current; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 480 | siginfo_t info; |
Brian Gerst | 9b6dba9 | 2010-03-21 09:00:44 -0400 | [diff] [blame] | 481 | unsigned short err; |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 482 | char *str = (trapnr == X86_TRAP_MF) ? "fpu exception" : |
| 483 | "simd exception"; |
Brian Gerst | e2e75c9 | 2010-03-21 09:00:45 -0400 | [diff] [blame] | 484 | |
| 485 | if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, SIGFPE) == NOTIFY_STOP) |
| 486 | return; |
| 487 | conditional_sti(regs); |
| 488 | |
| 489 | if (!user_mode_vm(regs)) |
| 490 | { |
| 491 | if (!fixup_exception(regs)) { |
| 492 | task->thread.error_code = error_code; |
Srikar Dronamraju | 51e7dc7 | 2012-03-12 14:55:55 +0530 | [diff] [blame] | 493 | task->thread.trap_nr = trapnr; |
Brian Gerst | e2e75c9 | 2010-03-21 09:00:45 -0400 | [diff] [blame] | 494 | die(str, regs, error_code); |
| 495 | } |
| 496 | return; |
| 497 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | |
| 499 | /* |
| 500 | * Save the info for the exception handler and clear the error. |
| 501 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | save_init_fpu(task); |
Srikar Dronamraju | 51e7dc7 | 2012-03-12 14:55:55 +0530 | [diff] [blame] | 503 | task->thread.trap_nr = trapnr; |
Brian Gerst | 9b6dba9 | 2010-03-21 09:00:44 -0400 | [diff] [blame] | 504 | task->thread.error_code = error_code; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | info.si_signo = SIGFPE; |
| 506 | info.si_errno = 0; |
Brian Gerst | 9b6dba9 | 2010-03-21 09:00:44 -0400 | [diff] [blame] | 507 | info.si_addr = (void __user *)regs->ip; |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 508 | if (trapnr == X86_TRAP_MF) { |
Brian Gerst | 9b6dba9 | 2010-03-21 09:00:44 -0400 | [diff] [blame] | 509 | unsigned short cwd, swd; |
| 510 | /* |
| 511 | * (~cwd & swd) will mask out exceptions that are not set to unmasked |
| 512 | * status. 0x3f is the exception bits in these regs, 0x200 is the |
| 513 | * C1 reg you need in case of a stack fault, 0x040 is the stack |
| 514 | * fault bit. We should only be taking one exception at a time, |
| 515 | * so if this combination doesn't produce any single exception, |
| 516 | * then we have a bad program that isn't synchronizing its FPU usage |
| 517 | * and it will suffer the consequences since we won't be able to |
| 518 | * fully reproduce the context of the exception |
| 519 | */ |
| 520 | cwd = get_fpu_cwd(task); |
| 521 | swd = get_fpu_swd(task); |
H. Peter Anvin | adf77ba | 2008-12-22 17:56:05 -0800 | [diff] [blame] | 522 | |
Brian Gerst | 9b6dba9 | 2010-03-21 09:00:44 -0400 | [diff] [blame] | 523 | err = swd & ~cwd; |
| 524 | } else { |
| 525 | /* |
| 526 | * The SIMD FPU exceptions are handled a little differently, as there |
| 527 | * is only a single status/control register. Thus, to determine which |
| 528 | * unmasked exception was caught we must mask the exception mask bits |
| 529 | * at 0x1f80, and then use these to mask the exception bits at 0x3f. |
| 530 | */ |
| 531 | unsigned short mxcsr = get_fpu_mxcsr(task); |
| 532 | err = ~(mxcsr >> 7) & mxcsr; |
| 533 | } |
H. Peter Anvin | adf77ba | 2008-12-22 17:56:05 -0800 | [diff] [blame] | 534 | |
| 535 | if (err & 0x001) { /* Invalid op */ |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 536 | /* |
| 537 | * swd & 0x240 == 0x040: Stack Underflow |
| 538 | * swd & 0x240 == 0x240: Stack Overflow |
| 539 | * User must clear the SF bit (0x40) if set |
| 540 | */ |
| 541 | info.si_code = FPE_FLTINV; |
H. Peter Anvin | adf77ba | 2008-12-22 17:56:05 -0800 | [diff] [blame] | 542 | } else if (err & 0x004) { /* Divide by Zero */ |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 543 | info.si_code = FPE_FLTDIV; |
H. Peter Anvin | adf77ba | 2008-12-22 17:56:05 -0800 | [diff] [blame] | 544 | } else if (err & 0x008) { /* Overflow */ |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 545 | info.si_code = FPE_FLTOVF; |
H. Peter Anvin | adf77ba | 2008-12-22 17:56:05 -0800 | [diff] [blame] | 546 | } else if (err & 0x012) { /* Denormal, Underflow */ |
| 547 | info.si_code = FPE_FLTUND; |
| 548 | } else if (err & 0x020) { /* Precision */ |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 549 | info.si_code = FPE_FLTRES; |
H. Peter Anvin | adf77ba | 2008-12-22 17:56:05 -0800 | [diff] [blame] | 550 | } else { |
Ingo Molnar | bd8b96d | 2008-12-26 09:20:22 +0100 | [diff] [blame] | 551 | /* |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 552 | * If we're using IRQ 13, or supposedly even some trap |
| 553 | * X86_TRAP_MF implementations, it's possible |
| 554 | * we get a spurious trap, which is not an error. |
Ingo Molnar | bd8b96d | 2008-12-26 09:20:22 +0100 | [diff] [blame] | 555 | */ |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 556 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | } |
| 558 | force_sig_info(SIGFPE, &info, task); |
| 559 | } |
| 560 | |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 561 | dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | { |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 563 | exception_enter(regs); |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 564 | math_error(regs, error_code, X86_TRAP_MF); |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 565 | exception_exit(regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | } |
| 567 | |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 568 | dotraplinkage void |
| 569 | do_simd_coprocessor_error(struct pt_regs *regs, long error_code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | { |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 571 | exception_enter(regs); |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 572 | math_error(regs, error_code, X86_TRAP_XF); |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 573 | exception_exit(regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | } |
| 575 | |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 576 | dotraplinkage void |
| 577 | do_spurious_interrupt_bug(struct pt_regs *regs, long error_code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | { |
Alexander van Heukelum | cf81978 | 2008-09-09 21:56:08 +0200 | [diff] [blame] | 579 | conditional_sti(regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | #if 0 |
| 581 | /* No need to warn about this any longer. */ |
Joe Perches | c767a54 | 2012-05-21 19:50:07 -0700 | [diff] [blame] | 582 | pr_info("Ignoring P6 Local APIC Spurious Interrupt Bug...\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 583 | #endif |
| 584 | } |
| 585 | |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 586 | asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void) |
| 587 | { |
| 588 | } |
| 589 | |
Andi Kleen | 7856f6c | 2009-04-28 23:32:56 +0200 | [diff] [blame] | 590 | asmlinkage void __attribute__((weak)) smp_threshold_interrupt(void) |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 591 | { |
| 592 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 593 | |
| 594 | /* |
Linus Torvalds | 34ddc81 | 2012-02-18 12:56:35 -0800 | [diff] [blame] | 595 | * 'math_state_restore()' saves the current math information in the |
| 596 | * old math state array, and gets the new ones from the current task |
| 597 | * |
| 598 | * Careful.. There are problems with IBM-designed IRQ13 behaviour. |
| 599 | * Don't touch unless you *really* know how it works. |
| 600 | * |
| 601 | * Must be called with kernel preemption disabled (eg with local |
| 602 | * local interrupts as in the case of do_device_not_available). |
| 603 | */ |
| 604 | void math_state_restore(void) |
| 605 | { |
| 606 | struct task_struct *tsk = current; |
| 607 | |
| 608 | if (!tsk_used_math(tsk)) { |
| 609 | local_irq_enable(); |
| 610 | /* |
| 611 | * does a slab alloc which can sleep |
| 612 | */ |
| 613 | if (init_fpu(tsk)) { |
| 614 | /* |
| 615 | * ran out of memory! |
| 616 | */ |
| 617 | do_group_exit(SIGKILL); |
| 618 | return; |
| 619 | } |
| 620 | local_irq_disable(); |
| 621 | } |
| 622 | |
| 623 | __thread_fpu_begin(tsk); |
Suresh Siddha | 304bced | 2012-08-24 14:13:02 -0700 | [diff] [blame] | 624 | |
Linus Torvalds | 80ab6f1 | 2012-02-19 11:48:44 -0800 | [diff] [blame] | 625 | /* |
| 626 | * Paranoid restore. send a SIGSEGV if we fail to restore the state. |
| 627 | */ |
| 628 | if (unlikely(restore_fpu_checking(tsk))) { |
Suresh Siddha | 304bced | 2012-08-24 14:13:02 -0700 | [diff] [blame] | 629 | drop_init_fpu(tsk); |
Linus Torvalds | 80ab6f1 | 2012-02-19 11:48:44 -0800 | [diff] [blame] | 630 | force_sig(SIGSEGV, tsk); |
| 631 | return; |
| 632 | } |
Linus Torvalds | b3b0870 | 2012-02-16 15:45:23 -0800 | [diff] [blame] | 633 | |
| 634 | tsk->fpu_counter++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | } |
Rusty Russell | 5992b6d | 2007-07-19 01:49:21 -0700 | [diff] [blame] | 636 | EXPORT_SYMBOL_GPL(math_state_restore); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 637 | |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 638 | dotraplinkage void __kprobes |
Brian Gerst | aa78bcf | 2009-02-10 09:51:45 -0500 | [diff] [blame] | 639 | do_device_not_available(struct pt_regs *regs, long error_code) |
Alexander van Heukelum | 7643e9b | 2008-09-09 21:56:02 +0200 | [diff] [blame] | 640 | { |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 641 | exception_enter(regs); |
Suresh Siddha | 5d2bd70 | 2012-09-06 14:58:52 -0700 | [diff] [blame] | 642 | BUG_ON(use_eager_fpu()); |
Suresh Siddha | 304bced | 2012-08-24 14:13:02 -0700 | [diff] [blame] | 643 | |
Brian Gerst | a334fe4 | 2010-09-03 21:17:15 -0400 | [diff] [blame] | 644 | #ifdef CONFIG_MATH_EMULATION |
Alexander van Heukelum | 7643e9b | 2008-09-09 21:56:02 +0200 | [diff] [blame] | 645 | if (read_cr0() & X86_CR0_EM) { |
Tejun Heo | d315760 | 2009-02-09 22:17:39 +0900 | [diff] [blame] | 646 | struct math_emu_info info = { }; |
| 647 | |
Alexander van Heukelum | 7643e9b | 2008-09-09 21:56:02 +0200 | [diff] [blame] | 648 | conditional_sti(regs); |
Tejun Heo | d315760 | 2009-02-09 22:17:39 +0900 | [diff] [blame] | 649 | |
Brian Gerst | aa78bcf | 2009-02-10 09:51:45 -0500 | [diff] [blame] | 650 | info.regs = regs; |
Tejun Heo | d315760 | 2009-02-09 22:17:39 +0900 | [diff] [blame] | 651 | math_emulate(&info); |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 652 | exception_exit(regs); |
Brian Gerst | a334fe4 | 2010-09-03 21:17:15 -0400 | [diff] [blame] | 653 | return; |
Alexander van Heukelum | 7643e9b | 2008-09-09 21:56:02 +0200 | [diff] [blame] | 654 | } |
Brian Gerst | a334fe4 | 2010-09-03 21:17:15 -0400 | [diff] [blame] | 655 | #endif |
| 656 | math_state_restore(); /* interrupts still off */ |
| 657 | #ifdef CONFIG_X86_32 |
| 658 | conditional_sti(regs); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 659 | #endif |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 660 | exception_exit(regs); |
Alexander van Heukelum | 7643e9b | 2008-09-09 21:56:02 +0200 | [diff] [blame] | 661 | } |
| 662 | |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 663 | #ifdef CONFIG_X86_32 |
Alexander van Heukelum | e407d620 | 2008-09-30 18:41:36 +0200 | [diff] [blame] | 664 | dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code) |
Alexander van Heukelum | f8e0870 | 2008-09-09 21:56:13 +0200 | [diff] [blame] | 665 | { |
| 666 | siginfo_t info; |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 667 | |
| 668 | exception_enter(regs); |
Alexander van Heukelum | f8e0870 | 2008-09-09 21:56:13 +0200 | [diff] [blame] | 669 | local_irq_enable(); |
| 670 | |
| 671 | info.si_signo = SIGILL; |
| 672 | info.si_errno = 0; |
| 673 | info.si_code = ILL_BADSTK; |
Hannes Eder | fc6fcdf | 2009-02-22 01:00:57 +0100 | [diff] [blame] | 674 | info.si_addr = NULL; |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 675 | if (notify_die(DIE_TRAP, "iret exception", regs, error_code, |
Frederic Weisbecker | 6ba3c97 | 2012-07-11 20:26:35 +0200 | [diff] [blame] | 676 | X86_TRAP_IRET, SIGILL) != NOTIFY_STOP) { |
| 677 | do_trap(X86_TRAP_IRET, SIGILL, "iret exception", regs, error_code, |
| 678 | &info); |
| 679 | } |
| 680 | exception_exit(regs); |
Alexander van Heukelum | f8e0870 | 2008-09-09 21:56:13 +0200 | [diff] [blame] | 681 | } |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 682 | #endif |
Alexander van Heukelum | f8e0870 | 2008-09-09 21:56:13 +0200 | [diff] [blame] | 683 | |
Jan Kiszka | 29c8439 | 2010-05-20 21:04:29 -0500 | [diff] [blame] | 684 | /* Set of traps needed for early debugging. */ |
| 685 | void __init early_trap_init(void) |
| 686 | { |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 687 | set_intr_gate_ist(X86_TRAP_DB, &debug, DEBUG_STACK); |
Jan Kiszka | 29c8439 | 2010-05-20 21:04:29 -0500 | [diff] [blame] | 688 | /* int3 can be called from all */ |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 689 | set_system_intr_gate_ist(X86_TRAP_BP, &int3, DEBUG_STACK); |
H. Peter Anvin | 8170e6b | 2013-01-24 12:19:52 -0800 | [diff] [blame] | 690 | #ifdef CONFIG_X86_32 |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 691 | set_intr_gate(X86_TRAP_PF, &page_fault); |
H. Peter Anvin | 8170e6b | 2013-01-24 12:19:52 -0800 | [diff] [blame] | 692 | #endif |
Jan Kiszka | 29c8439 | 2010-05-20 21:04:29 -0500 | [diff] [blame] | 693 | load_idt(&idt_descr); |
| 694 | } |
| 695 | |
H. Peter Anvin | 8170e6b | 2013-01-24 12:19:52 -0800 | [diff] [blame] | 696 | void __init early_trap_pf_init(void) |
| 697 | { |
| 698 | #ifdef CONFIG_X86_64 |
| 699 | set_intr_gate(X86_TRAP_PF, &page_fault); |
| 700 | #endif |
| 701 | } |
| 702 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | void __init trap_init(void) |
| 704 | { |
Rusty Russell | dbeb2be | 2007-10-19 20:35:03 +0200 | [diff] [blame] | 705 | int i; |
| 706 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | #ifdef CONFIG_EISA |
Ingo Molnar | 927222b | 2008-01-30 13:33:49 +0100 | [diff] [blame] | 708 | void __iomem *p = early_ioremap(0x0FFFD9, 4); |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 709 | |
| 710 | if (readl(p) == 'E' + ('I'<<8) + ('S'<<16) + ('A'<<24)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | EISA_bus = 1; |
Ingo Molnar | 927222b | 2008-01-30 13:33:49 +0100 | [diff] [blame] | 712 | early_iounmap(p, 4); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | #endif |
| 714 | |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 715 | set_intr_gate(X86_TRAP_DE, ÷_error); |
| 716 | set_intr_gate_ist(X86_TRAP_NMI, &nmi, NMI_STACK); |
Alexander van Heukelum | 699d293 | 2008-10-03 22:00:32 +0200 | [diff] [blame] | 717 | /* int4 can be called from all */ |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 718 | set_system_intr_gate(X86_TRAP_OF, &overflow); |
| 719 | set_intr_gate(X86_TRAP_BR, &bounds); |
| 720 | set_intr_gate(X86_TRAP_UD, &invalid_op); |
| 721 | set_intr_gate(X86_TRAP_NM, &device_not_available); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 722 | #ifdef CONFIG_X86_32 |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 723 | set_task_gate(X86_TRAP_DF, GDT_ENTRY_DOUBLEFAULT_TSS); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 724 | #else |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 725 | set_intr_gate_ist(X86_TRAP_DF, &double_fault, DOUBLEFAULT_STACK); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 726 | #endif |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 727 | set_intr_gate(X86_TRAP_OLD_MF, &coprocessor_segment_overrun); |
| 728 | set_intr_gate(X86_TRAP_TS, &invalid_TSS); |
| 729 | set_intr_gate(X86_TRAP_NP, &segment_not_present); |
| 730 | set_intr_gate_ist(X86_TRAP_SS, &stack_segment, STACKFAULT_STACK); |
| 731 | set_intr_gate(X86_TRAP_GP, &general_protection); |
| 732 | set_intr_gate(X86_TRAP_SPURIOUS, &spurious_interrupt_bug); |
| 733 | set_intr_gate(X86_TRAP_MF, &coprocessor_error); |
| 734 | set_intr_gate(X86_TRAP_AC, &alignment_check); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | #ifdef CONFIG_X86_MCE |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 736 | set_intr_gate_ist(X86_TRAP_MC, &machine_check, MCE_STACK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | #endif |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 738 | set_intr_gate(X86_TRAP_XF, &simd_coprocessor_error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 739 | |
Yinghai Lu | bb3f0b5 | 2009-01-25 02:38:09 -0800 | [diff] [blame] | 740 | /* Reserve all the builtin and the syscall vector: */ |
| 741 | for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++) |
| 742 | set_bit(i, used_vectors); |
| 743 | |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 744 | #ifdef CONFIG_IA32_EMULATION |
| 745 | set_system_intr_gate(IA32_SYSCALL_VECTOR, ia32_syscall); |
Yinghai Lu | bb3f0b5 | 2009-01-25 02:38:09 -0800 | [diff] [blame] | 746 | set_bit(IA32_SYSCALL_VECTOR, used_vectors); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 747 | #endif |
| 748 | |
| 749 | #ifdef CONFIG_X86_32 |
Alexander van Heukelum | 699d293 | 2008-10-03 22:00:32 +0200 | [diff] [blame] | 750 | set_system_trap_gate(SYSCALL_VECTOR, &system_call); |
Rusty Russell | dbeb2be | 2007-10-19 20:35:03 +0200 | [diff] [blame] | 751 | set_bit(SYSCALL_VECTOR, used_vectors); |
Alexander van Heukelum | 081f75b | 2008-10-03 22:00:39 +0200 | [diff] [blame] | 752 | #endif |
Yinghai Lu | bb3f0b5 | 2009-01-25 02:38:09 -0800 | [diff] [blame] | 753 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | /* |
Ingo Molnar | b596440 | 2008-02-26 11:15:50 +0100 | [diff] [blame] | 755 | * Should be a barrier for any external CPU state: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | */ |
| 757 | cpu_init(); |
| 758 | |
Thomas Gleixner | 428cf90 | 2009-08-20 10:35:46 +0200 | [diff] [blame] | 759 | x86_init.irqs.trap_init(); |
Steven Rostedt | 228bdaa | 2011-12-09 03:02:19 -0500 | [diff] [blame] | 760 | |
| 761 | #ifdef CONFIG_X86_64 |
| 762 | memcpy(&nmi_idt_table, &idt_table, IDT_ENTRIES * 16); |
Kees Cook | c940826 | 2012-03-09 16:07:10 -0800 | [diff] [blame] | 763 | set_nmi_gate(X86_TRAP_DB, &debug); |
| 764 | set_nmi_gate(X86_TRAP_BP, &int3); |
Steven Rostedt | 228bdaa | 2011-12-09 03:02:19 -0500 | [diff] [blame] | 765 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 766 | } |