[linux-2.6-block.git] / arch / arm64 / kernel / traps.c

/*
 * Based on arch/arm/kernel/traps.c
 *
 * Copyright (C) 1995-2009 Russell King
 * Copyright (C) 2012 ARM Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/signal.h>
#include <linux/personality.h>
#include <linux/kallsyms.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/hardirq.h>
#include <linux/kdebug.h>
#include <linux/module.h>
#include <linux/kexec.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/syscalls.h>

#include <asm/atomic.h>
#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/traps.h>
#include <asm/stacktrace.h>
#include <asm/exception.h>
#include <asm/system_misc.h>

static const char *handler[]= {
	"Synchronous Abort",
	"IRQ",
	"FIQ",
	"Error"
};

int show_unhandled_signals = 1;

/*
 * Dump out the contents of some memory nicely...
 */
static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
		     unsigned long top)
{
	unsigned long first;
	mm_segment_t fs;
	int i;

	/*
	 * We need to switch to kernel mode so that we can use __get_user
	 * to safely read from kernel space.  Note that we now dump the
	 * code first, just in case the backtrace kills us.
	 */
	fs = get_fs();
	set_fs(KERNEL_DS);

	printk("%s%s(0x%016lx to 0x%016lx)\n", lvl, str, bottom, top);

	for (first = bottom & ~31; first < top; first += 32) {
		unsigned long p;
		char str[sizeof(" 12345678") * 8 + 1];

		memset(str, ' ', sizeof(str));
		str[sizeof(str) - 1] = '\0';

		for (p = first, i = 0; i < 8 && p < top; i++, p += 4) {
			if (p >= bottom && p < top) {
				unsigned int val;
				if (__get_user(val, (unsigned int *)p) == 0)
					sprintf(str + i * 9, " %08x", val);
				else
					sprintf(str + i * 9, " ????????");
			}
		}
		printk("%s%04lx:%s\n", lvl, first & 0xffff, str);
	}

	set_fs(fs);
}

static void dump_backtrace_entry(unsigned long where, unsigned long stack)
{
	print_ip_sym(where);
	if (in_exception_text(where))
		dump_mem("", "Exception stack", stack,
			 stack + sizeof(struct pt_regs));
}

static void dump_instr(const char *lvl, struct pt_regs *regs)
{
	unsigned long addr = instruction_pointer(regs);
	mm_segment_t fs;
	char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
	int i;

	/*
	 * We need to switch to kernel mode so that we can use __get_user
	 * to safely read from kernel space.  Note that we now dump the
	 * code first, just in case the backtrace kills us.
	 */
	fs = get_fs();
	set_fs(KERNEL_DS);

	for (i = -4; i < 1; i++) {
		unsigned int val, bad;

		bad = __get_user(val, &((u32 *)addr)[i]);

		if (!bad)
			p += sprintf(p, i == 0 ? "(%08x) " : "%08x ", val);
		else {
			p += sprintf(p, "bad PC value");
			break;
		}
	}
	printk("%sCode: %s\n", lvl, str);

	set_fs(fs);
}

static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
{
	struct stackframe frame;

	pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);

	if (!tsk)
		tsk = current;

	if (regs) {
		frame.fp = regs->regs[29];
		frame.sp = regs->sp;
		frame.pc = regs->pc;
	} else if (tsk == current) {
		frame.fp = (unsigned long)__builtin_frame_address(0);
		frame.sp = current_stack_pointer;
		frame.pc = (unsigned long)dump_backtrace;
	} else {
		/*
		 * task blocked in __switch_to
		 */
		frame.fp = thread_saved_fp(tsk);
		frame.sp = thread_saved_sp(tsk);
		frame.pc = thread_saved_pc(tsk);
	}

	pr_emerg("Call trace:\n");
	while (1) {
		unsigned long where = frame.pc;
		int ret;

		ret = unwind_frame(&frame);
		if (ret < 0)
			break;
		dump_backtrace_entry(where, frame.sp);
	}
}

void show_stack(struct task_struct *tsk, unsigned long *sp)
{
	dump_backtrace(NULL, tsk);
	barrier();
}

#ifdef CONFIG_PREEMPT
#define S_PREEMPT " PREEMPT"
#else
#define S_PREEMPT ""
#endif
#ifdef CONFIG_SMP
#define S_SMP " SMP"
#else
#define S_SMP ""
#endif

static int __die(const char *str, int err, struct thread_info *thread,
		 struct pt_regs *regs)
{
	struct task_struct *tsk = thread->task;
	static int die_counter;
	int ret;

	pr_emerg("Internal error: %s: %x [#%d]" S_PREEMPT S_SMP "\n",
		 str, err, ++die_counter);

	/* trap and error numbers are mostly meaningless on ARM */
	ret = notify_die(DIE_OOPS, str, regs, err, 0, SIGSEGV);
	if (ret == NOTIFY_STOP)
		return ret;

	print_modules();
	__show_regs(regs);
	pr_emerg("Process %.*s (pid: %d, stack limit = 0x%p)\n",
		 TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1);

	if (!user_mode(regs) || in_interrupt()) {
		dump_mem(KERN_EMERG, "Stack: ", regs->sp,
			 THREAD_SIZE + (unsigned long)task_stack_page(tsk));
		dump_backtrace(regs, tsk);
		dump_instr(KERN_EMERG, regs);
	}

	return ret;
}

static DEFINE_RAW_SPINLOCK(die_lock);

/*
 * This function is protected against re-entrancy.
 */
void die(const char *str, struct pt_regs *regs, int err)
{
	struct thread_info *thread = current_thread_info();
	int ret;

	oops_enter();

	raw_spin_lock_irq(&die_lock);
	console_verbose();
	bust_spinlocks(1);
	ret = __die(str, err, thread, regs);

	if (regs && kexec_should_crash(thread->task))
		crash_kexec(regs);

	bust_spinlocks(0);
	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
	raw_spin_unlock_irq(&die_lock);
	oops_exit();

	if (in_interrupt())
		panic("Fatal exception in interrupt");
	if (panic_on_oops)
		panic("Fatal exception");
	if (ret != NOTIFY_STOP)
		do_exit(SIGSEGV);
}

void arm64_notify_die(const char *str, struct pt_regs *regs,
		      struct siginfo *info, int err)
{
	if (user_mode(regs)) {
		current->thread.fault_address = 0;
		current->thread.fault_code = err;
		force_sig_info(info->si_signo, info, current);
	} else {
		die(str, regs, err);
	}
}

static LIST_HEAD(undef_hook);
static DEFINE_RAW_SPINLOCK(undef_lock);

void register_undef_hook(struct undef_hook *hook)
{
	unsigned long flags;

	raw_spin_lock_irqsave(&undef_lock, flags);
	list_add(&hook->node, &undef_hook);
	raw_spin_unlock_irqrestore(&undef_lock, flags);
}

void unregister_undef_hook(struct undef_hook *hook)
{
	unsigned long flags;

	raw_spin_lock_irqsave(&undef_lock, flags);
	list_del(&hook->node);
	raw_spin_unlock_irqrestore(&undef_lock, flags);
}

static int call_undef_hook(struct pt_regs *regs)
{
	struct undef_hook *hook;
	unsigned long flags;
	u32 instr;
	int (*fn)(struct pt_regs *regs, u32 instr) = NULL;
	void __user *pc = (void __user *)instruction_pointer(regs);

	if (!user_mode(regs))
		return 1;

	if (compat_thumb_mode(regs)) {
		/* 16-bit Thumb instruction */
		if (get_user(instr, (u16 __user *)pc))
			goto exit;
		instr = le16_to_cpu(instr);
		if (aarch32_insn_is_wide(instr)) {
			u32 instr2;

			if (get_user(instr2, (u16 __user *)(pc + 2)))
				goto exit;
			instr2 = le16_to_cpu(instr2);
			instr = (instr << 16) | instr2;
		}
	} else {
		/* 32-bit ARM instruction */
		if (get_user(instr, (u32 __user *)pc))
			goto exit;
		instr = le32_to_cpu(instr);
	}

	raw_spin_lock_irqsave(&undef_lock, flags);
	list_for_each_entry(hook, &undef_hook, node)
		if ((instr & hook->instr_mask) == hook->instr_val &&
			(regs->pstate & hook->pstate_mask) == hook->pstate_val)
			fn = hook->fn;

	raw_spin_unlock_irqrestore(&undef_lock, flags);
exit:
	return fn ? fn(regs, instr) : 1;
}

asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
{
	siginfo_t info;
	void __user *pc = (void __user *)instruction_pointer(regs);

	/* check for AArch32 breakpoint instructions */
	if (!aarch32_break_handler(regs))
		return;

	if (call_undef_hook(regs) == 0)
		return;

	if (show_unhandled_signals_ratelimited() && unhandled_signal(current, SIGILL)) {
		pr_info("%s[%d]: undefined instruction: pc=%p\n",
			current->comm, task_pid_nr(current), pc);
		dump_instr(KERN_INFO, regs);
	}

	info.si_signo = SIGILL;
	info.si_errno = 0;
	info.si_code  = ILL_ILLOPC;
	info.si_addr  = pc;

	arm64_notify_die("Oops - undefined instruction", regs, &info, 0);
}

long compat_arm_syscall(struct pt_regs *regs);

asmlinkage long do_ni_syscall(struct pt_regs *regs)
{
#ifdef CONFIG_COMPAT
	long ret;
	if (is_compat_task()) {
		ret = compat_arm_syscall(regs);
		if (ret != -ENOSYS)
			return ret;
	}
#endif

	if (show_unhandled_signals_ratelimited()) {
		pr_info("%s[%d]: syscall %d\n", current->comm,
			task_pid_nr(current), (int)regs->syscallno);
		dump_instr("", regs);
		if (user_mode(regs))
			__show_regs(regs);
	}

	return sys_ni_syscall();
}

static const char *esr_class_str[] = {
	[0 ... ESR_ELx_EC_MAX]		= "UNRECOGNIZED EC",
	[ESR_ELx_EC_UNKNOWN]		= "Unknown/Uncategorized",
	[ESR_ELx_EC_WFx]		= "WFI/WFE",
	[ESR_ELx_EC_CP15_32]		= "CP15 MCR/MRC",
	[ESR_ELx_EC_CP15_64]		= "CP15 MCRR/MRRC",
	[ESR_ELx_EC_CP14_MR]		= "CP14 MCR/MRC",
	[ESR_ELx_EC_CP14_LS]		= "CP14 LDC/STC",
	[ESR_ELx_EC_FP_ASIMD]		= "ASIMD",
	[ESR_ELx_EC_CP10_ID]		= "CP10 MRC/VMRS",
	[ESR_ELx_EC_CP14_64]		= "CP14 MCRR/MRRC",
	[ESR_ELx_EC_ILL]		= "PSTATE.IL",
	[ESR_ELx_EC_SVC32]		= "SVC (AArch32)",
	[ESR_ELx_EC_HVC32]		= "HVC (AArch32)",
	[ESR_ELx_EC_SMC32]		= "SMC (AArch32)",
	[ESR_ELx_EC_SVC64]		= "SVC (AArch64)",
	[ESR_ELx_EC_HVC64]		= "HVC (AArch64)",
	[ESR_ELx_EC_SMC64]		= "SMC (AArch64)",
	[ESR_ELx_EC_SYS64]		= "MSR/MRS (AArch64)",
	[ESR_ELx_EC_IMP_DEF]		= "EL3 IMP DEF",
	[ESR_ELx_EC_IABT_LOW]		= "IABT (lower EL)",
	[ESR_ELx_EC_IABT_CUR]		= "IABT (current EL)",
	[ESR_ELx_EC_PC_ALIGN]		= "PC Alignment",
	[ESR_ELx_EC_DABT_LOW]		= "DABT (lower EL)",
	[ESR_ELx_EC_DABT_CUR]		= "DABT (current EL)",
	[ESR_ELx_EC_SP_ALIGN]		= "SP Alignment",
	[ESR_ELx_EC_FP_EXC32]		= "FP (AArch32)",
	[ESR_ELx_EC_FP_EXC64]		= "FP (AArch64)",
	[ESR_ELx_EC_SERROR]		= "SError",
	[ESR_ELx_EC_BREAKPT_LOW]	= "Breakpoint (lower EL)",
	[ESR_ELx_EC_BREAKPT_CUR]	= "Breakpoint (current EL)",
	[ESR_ELx_EC_SOFTSTP_LOW]	= "Software Step (lower EL)",
	[ESR_ELx_EC_SOFTSTP_CUR]	= "Software Step (current EL)",
	[ESR_ELx_EC_WATCHPT_LOW]	= "Watchpoint (lower EL)",
	[ESR_ELx_EC_WATCHPT_CUR]	= "Watchpoint (current EL)",
	[ESR_ELx_EC_BKPT32]		= "BKPT (AArch32)",
	[ESR_ELx_EC_VECTOR32]		= "Vector catch (AArch32)",
	[ESR_ELx_EC_BRK64]		= "BRK (AArch64)",
};

const char *esr_get_class_string(u32 esr)
{
	return esr_class_str[esr >> ESR_ELx_EC_SHIFT];
}

/*
 * bad_mode handles the impossible case in the exception vector.
 */
asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
{
	siginfo_t info;
	void __user *pc = (void __user *)instruction_pointer(regs);
	console_verbose();

	pr_crit("Bad mode in %s handler detected, code 0x%08x -- %s\n",
		handler[reason], esr, esr_get_class_string(esr));
	__show_regs(regs);

	info.si_signo = SIGILL;
	info.si_errno = 0;
	info.si_code  = ILL_ILLOPC;
	info.si_addr  = pc;

	arm64_notify_die("Oops - bad mode", regs, &info, 0);
}

void __pte_error(const char *file, int line, unsigned long val)
{
	pr_crit("%s:%d: bad pte %016lx.\n", file, line, val);
}

void __pmd_error(const char *file, int line, unsigned long val)
{
	pr_crit("%s:%d: bad pmd %016lx.\n", file, line, val);
}

void __pud_error(const char *file, int line, unsigned long val)
{
	pr_crit("%s:%d: bad pud %016lx.\n", file, line, val);
}

void __pgd_error(const char *file, int line, unsigned long val)
{
	pr_crit("%s:%d: bad pgd %016lx.\n", file, line, val);
}

void __init trap_init(void)
{
	return;
}
Commit	Line	Data
60ffc30d CM	1	/*
	2	* Based on arch/arm/kernel/traps.c
	3	*
	4	* Copyright (C) 1995-2009 Russell King
	5	* Copyright (C) 2012 ARM Ltd.
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	18	*/
	19
	20	#include <linux/signal.h>
	21	#include <linux/personality.h>
	22	#include <linux/kallsyms.h>
	23	#include <linux/spinlock.h>
	24	#include <linux/uaccess.h>
	25	#include <linux/hardirq.h>
	26	#include <linux/kdebug.h>
	27	#include <linux/module.h>
	28	#include <linux/kexec.h>
	29	#include <linux/delay.h>
	30	#include <linux/init.h>
	31	#include <linux/sched.h>
	32	#include <linux/syscalls.h>
	33
	34	#include <asm/atomic.h>
1442b6ed	35	#include <asm/debug-monitors.h>
60a1f02c	36	#include <asm/esr.h>
60ffc30d CM	37	#include <asm/traps.h>
	38	#include <asm/stacktrace.h>
	39	#include <asm/exception.h>
	40	#include <asm/system_misc.h>
	41
	42	static const char *handler[]= {
	43	"Synchronous Abort",
	44	"IRQ",
	45	"FIQ",
	46	"Error"
	47	};
	48
	49	int show_unhandled_signals = 1;
	50
	51	/*
	52	* Dump out the contents of some memory nicely...
	53	*/
	54	static void dump_mem(const char lvl, const char str, unsigned long bottom,
	55	unsigned long top)
	56	{
	57	unsigned long first;
	58	mm_segment_t fs;
	59	int i;
	60
	61	/*
	62	* We need to switch to kernel mode so that we can use __get_user
	63	* to safely read from kernel space. Note that we now dump the
	64	* code first, just in case the backtrace kills us.
	65	*/
	66	fs = get_fs();
	67	set_fs(KERNEL_DS);
	68
	69	printk("%s%s(0x%016lx to 0x%016lx)\n", lvl, str, bottom, top);
	70
	71	for (first = bottom & ~31; first < top; first += 32) {
	72	unsigned long p;
	73	char str[sizeof(" 12345678") * 8 + 1];
	74
	75	memset(str, ' ', sizeof(str));
	76	str[sizeof(str) - 1] = '\0';
	77
	78	for (p = first, i = 0; i < 8 && p < top; i++, p += 4) {
	79	if (p >= bottom && p < top) {
	80	unsigned int val;
	81	if (__get_user(val, (unsigned int *)p) == 0)
	82	sprintf(str + i * 9, " %08x", val);
	83	else
	84	sprintf(str + i * 9, " ????????");
	85	}
	86	}
	87	printk("%s%04lx:%s\n", lvl, first & 0xffff, str);
	88	}
	89
	90	set_fs(fs);
	91	}
	92
	93	static void dump_backtrace_entry(unsigned long where, unsigned long stack)
	94	{
	95	print_ip_sym(where);
	96	if (in_exception_text(where))
	97	dump_mem("", "Exception stack", stack,
	98	stack + sizeof(struct pt_regs));
	99	}
	100
101	static void dump_instr(const char lvl, struct pt_regs regs)
102	{
103	unsigned long addr = instruction_pointer(regs);
104	mm_segment_t fs;
105	char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
106	int i;
107
108	/*
109	* We need to switch to kernel mode so that we can use __get_user
110	* to safely read from kernel space. Note that we now dump the
111	* code first, just in case the backtrace kills us.
112	*/
113	fs = get_fs();
114	set_fs(KERNEL_DS);
115
116	for (i = -4; i < 1; i++) {
117	unsigned int val, bad;
118
119	bad = __get_user(val, &((u32 *)addr)[i]);
120
121	if (!bad)
122	p += sprintf(p, i == 0 ? "(%08x) " : "%08x ", val);
123	else {
124	p += sprintf(p, "bad PC value");
125	break;
126	}
127	}
128	printk("%sCode: %s\n", lvl, str);
129
130	set_fs(fs);
131	}
132
133	static void dump_backtrace(struct pt_regs regs, struct task_struct tsk)
134	{
135	struct stackframe frame;
60ffc30d CM	136
	137	pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
	138
	139	if (!tsk)
	140	tsk = current;
	141
	142	if (regs) {
	143	frame.fp = regs->regs[29];
	144	frame.sp = regs->sp;
	145	frame.pc = regs->pc;
	146	} else if (tsk == current) {
	147	frame.fp = (unsigned long)__builtin_frame_address(0);
2128df14	148	frame.sp = current_stack_pointer;
60ffc30d CM	149	frame.pc = (unsigned long)dump_backtrace;
	150	} else {
	151	/*
	152	* task blocked in __switch_to
	153	*/
	154	frame.fp = thread_saved_fp(tsk);
	155	frame.sp = thread_saved_sp(tsk);
	156	frame.pc = thread_saved_pc(tsk);
	157	}
	158
ac7b406c	159	pr_emerg("Call trace:\n");
60ffc30d CM	160	while (1) {
	161	unsigned long where = frame.pc;
	162	int ret;
	163
	164	ret = unwind_frame(&frame);
	165	if (ret < 0)
	166	break;
	167	dump_backtrace_entry(where, frame.sp);
	168	}
	169	}
	170
60ffc30d CM	171	void show_stack(struct task_struct tsk, unsigned long sp)
	172	{
	173	dump_backtrace(NULL, tsk);
	174	barrier();
	175	}
	176
	177	#ifdef CONFIG_PREEMPT
	178	#define S_PREEMPT " PREEMPT"
	179	#else
	180	#define S_PREEMPT ""
	181	#endif
	182	#ifdef CONFIG_SMP
	183	#define S_SMP " SMP"
	184	#else
	185	#define S_SMP ""
	186	#endif
	187
	188	static int __die(const char str, int err, struct thread_info thread,
	189	struct pt_regs *regs)
	190	{
	191	struct task_struct *tsk = thread->task;
	192	static int die_counter;
	193	int ret;
	194
	195	pr_emerg("Internal error: %s: %x [#%d]" S_PREEMPT S_SMP "\n",
	196	str, err, ++die_counter);
	197
	198	/* trap and error numbers are mostly meaningless on ARM */
	199	ret = notify_die(DIE_OOPS, str, regs, err, 0, SIGSEGV);
	200	if (ret == NOTIFY_STOP)
	201	return ret;
	202
	203	print_modules();
	204	__show_regs(regs);
	205	pr_emerg("Process %.*s (pid: %d, stack limit = 0x%p)\n",
	206	TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1);
	207
	208	if (!user_mode(regs) \|\| in_interrupt()) {
	209	dump_mem(KERN_EMERG, "Stack: ", regs->sp,
	210	THREAD_SIZE + (unsigned long)task_stack_page(tsk));
	211	dump_backtrace(regs, tsk);
	212	dump_instr(KERN_EMERG, regs);
	213	}
	214
	215	return ret;
	216	}
	217
	218	static DEFINE_RAW_SPINLOCK(die_lock);
	219
	220	/*
	221	* This function is protected against re-entrancy.
	222	*/
	223	void die(const char str, struct pt_regs regs, int err)
	224	{
	225	struct thread_info *thread = current_thread_info();
	226	int ret;
	227
	228	oops_enter();
	229
	230	raw_spin_lock_irq(&die_lock);
	231	console_verbose();
	232	bust_spinlocks(1);
	233	ret = __die(str, err, thread, regs);
	234
235	if (regs && kexec_should_crash(thread->task))
236	crash_kexec(regs);
237
238	bust_spinlocks(0);
373d4d09	239	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
60ffc30d CM	240	raw_spin_unlock_irq(&die_lock);
	241	oops_exit();
	242
	243	if (in_interrupt())
	244	panic("Fatal exception in interrupt");
	245	if (panic_on_oops)
	246	panic("Fatal exception");
	247	if (ret != NOTIFY_STOP)
	248	do_exit(SIGSEGV);
	249	}
	250
	251	void arm64_notify_die(const char str, struct pt_regs regs,
	252	struct siginfo *info, int err)
	253	{
9141300a CM	254	if (user_mode(regs)) {
	255	current->thread.fault_address = 0;
	256	current->thread.fault_code = err;
60ffc30d	257	force_sig_info(info->si_signo, info, current);
9141300a	258	} else {
60ffc30d	259	die(str, regs, err);
9141300a	260	}
60ffc30d CM	261	}
60ffc30d CM	262
9b79f52d PA	263	static LIST_HEAD(undef_hook);
	264	static DEFINE_RAW_SPINLOCK(undef_lock);
	265
	266	void register_undef_hook(struct undef_hook *hook)
	267	{
	268	unsigned long flags;
	269
	270	raw_spin_lock_irqsave(&undef_lock, flags);
	271	list_add(&hook->node, &undef_hook);
	272	raw_spin_unlock_irqrestore(&undef_lock, flags);
	273	}
	274
	275	void unregister_undef_hook(struct undef_hook *hook)
	276	{
	277	unsigned long flags;
	278
	279	raw_spin_lock_irqsave(&undef_lock, flags);
	280	list_del(&hook->node);
	281	raw_spin_unlock_irqrestore(&undef_lock, flags);
	282	}
	283
	284	static int call_undef_hook(struct pt_regs *regs)
	285	{
	286	struct undef_hook *hook;
	287	unsigned long flags;
	288	u32 instr;
	289	int (fn)(struct pt_regs regs, u32 instr) = NULL;
	290	void __user pc = (void __user )instruction_pointer(regs);
	291
	292	if (!user_mode(regs))
	293	return 1;
	294
	295	if (compat_thumb_mode(regs)) {
	296	/* 16-bit Thumb instruction */
	297	if (get_user(instr, (u16 __user *)pc))
	298	goto exit;
	299	instr = le16_to_cpu(instr);
	300	if (aarch32_insn_is_wide(instr)) {
	301	u32 instr2;
	302
	303	if (get_user(instr2, (u16 __user *)(pc + 2)))
	304	goto exit;
	305	instr2 = le16_to_cpu(instr2);
	306	instr = (instr << 16) \| instr2;
	307	}
	308	} else {
	309	/* 32-bit ARM instruction */
	310	if (get_user(instr, (u32 __user *)pc))
	311	goto exit;
	312	instr = le32_to_cpu(instr);
	313	}
	314
	315	raw_spin_lock_irqsave(&undef_lock, flags);
	316	list_for_each_entry(hook, &undef_hook, node)
	317	if ((instr & hook->instr_mask) == hook->instr_val &&
	318	(regs->pstate & hook->pstate_mask) == hook->pstate_val)
	319	fn = hook->fn;
	320
	321	raw_spin_unlock_irqrestore(&undef_lock, flags);
	322	exit:
	323	return fn ? fn(regs, instr) : 1;
	324	}
	325
60ffc30d CM	326	asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
	327	{
	328	siginfo_t info;
	329	void __user pc = (void __user )instruction_pointer(regs);
	330
60ffc30d	331	/* check for AArch32 breakpoint instructions */
1442b6ed	332	if (!aarch32_break_handler(regs))
60ffc30d	333	return;
60ffc30d	334
9b79f52d PA	335	if (call_undef_hook(regs) == 0)
	336	return;
	337
86dca36e	338	if (show_unhandled_signals_ratelimited() && unhandled_signal(current, SIGILL)) {
60ffc30d CM	339	pr_info("%s[%d]: undefined instruction: pc=%p\n",
	340	current->comm, task_pid_nr(current), pc);
	341	dump_instr(KERN_INFO, regs);
	342	}
	343
	344	info.si_signo = SIGILL;
	345	info.si_errno = 0;
	346	info.si_code = ILL_ILLOPC;
	347	info.si_addr = pc;
	348
	349	arm64_notify_die("Oops - undefined instruction", regs, &info, 0);
	350	}
	351
	352	long compat_arm_syscall(struct pt_regs *regs);
	353
	354	asmlinkage long do_ni_syscall(struct pt_regs *regs)
	355	{
	356	#ifdef CONFIG_COMPAT
	357	long ret;
	358	if (is_compat_task()) {
	359	ret = compat_arm_syscall(regs);
	360	if (ret != -ENOSYS)
	361	return ret;
	362	}
	363	#endif
	364
86dca36e	365	if (show_unhandled_signals_ratelimited()) {
60ffc30d CM	366	pr_info("%s[%d]: syscall %d\n", current->comm,
	367	task_pid_nr(current), (int)regs->syscallno);
	368	dump_instr("", regs);
	369	if (user_mode(regs))
	370	__show_regs(regs);
	371	}
	372
	373	return sys_ni_syscall();
	374	}
	375
60a1f02c MR	376	static const char *esr_class_str[] = {
	377	[0 ... ESR_ELx_EC_MAX] = "UNRECOGNIZED EC",
	378	[ESR_ELx_EC_UNKNOWN] = "Unknown/Uncategorized",
	379	[ESR_ELx_EC_WFx] = "WFI/WFE",
	380	[ESR_ELx_EC_CP15_32] = "CP15 MCR/MRC",
	381	[ESR_ELx_EC_CP15_64] = "CP15 MCRR/MRRC",
	382	[ESR_ELx_EC_CP14_MR] = "CP14 MCR/MRC",
	383	[ESR_ELx_EC_CP14_LS] = "CP14 LDC/STC",
	384	[ESR_ELx_EC_FP_ASIMD] = "ASIMD",
	385	[ESR_ELx_EC_CP10_ID] = "CP10 MRC/VMRS",
	386	[ESR_ELx_EC_CP14_64] = "CP14 MCRR/MRRC",
	387	[ESR_ELx_EC_ILL] = "PSTATE.IL",
	388	[ESR_ELx_EC_SVC32] = "SVC (AArch32)",
	389	[ESR_ELx_EC_HVC32] = "HVC (AArch32)",
	390	[ESR_ELx_EC_SMC32] = "SMC (AArch32)",
	391	[ESR_ELx_EC_SVC64] = "SVC (AArch64)",
	392	[ESR_ELx_EC_HVC64] = "HVC (AArch64)",
	393	[ESR_ELx_EC_SMC64] = "SMC (AArch64)",
	394	[ESR_ELx_EC_SYS64] = "MSR/MRS (AArch64)",
	395	[ESR_ELx_EC_IMP_DEF] = "EL3 IMP DEF",
	396	[ESR_ELx_EC_IABT_LOW] = "IABT (lower EL)",
	397	[ESR_ELx_EC_IABT_CUR] = "IABT (current EL)",
	398	[ESR_ELx_EC_PC_ALIGN] = "PC Alignment",
	399	[ESR_ELx_EC_DABT_LOW] = "DABT (lower EL)",
	400	[ESR_ELx_EC_DABT_CUR] = "DABT (current EL)",
	401	[ESR_ELx_EC_SP_ALIGN] = "SP Alignment",
	402	[ESR_ELx_EC_FP_EXC32] = "FP (AArch32)",
	403	[ESR_ELx_EC_FP_EXC64] = "FP (AArch64)",
	404	[ESR_ELx_EC_SERROR] = "SError",
	405	[ESR_ELx_EC_BREAKPT_LOW] = "Breakpoint (lower EL)",
	406	[ESR_ELx_EC_BREAKPT_CUR] = "Breakpoint (current EL)",
	407	[ESR_ELx_EC_SOFTSTP_LOW] = "Software Step (lower EL)",
	408	[ESR_ELx_EC_SOFTSTP_CUR] = "Software Step (current EL)",
	409	[ESR_ELx_EC_WATCHPT_LOW] = "Watchpoint (lower EL)",
	410	[ESR_ELx_EC_WATCHPT_CUR] = "Watchpoint (current EL)",
	411	[ESR_ELx_EC_BKPT32] = "BKPT (AArch32)",
	412	[ESR_ELx_EC_VECTOR32] = "Vector catch (AArch32)",
	413	[ESR_ELx_EC_BRK64] = "BRK (AArch64)",
	414	};
	415
	416	const char *esr_get_class_string(u32 esr)
	417	{
	418	return esr_class_str[esr >> ESR_ELx_EC_SHIFT];
	419	}
	420
60ffc30d CM	421	/*
	422	* bad_mode handles the impossible case in the exception vector.
	423	*/
	424	asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
	425	{
9955ac47 MR	426	siginfo_t info;
9955ac47 MR	427	void __user pc = (void __user )instruction_pointer(regs);
60ffc30d CM	428	console_verbose();
60ffc30d CM	429
60a1f02c MR	430	pr_crit("Bad mode in %s handler detected, code 0x%08x -- %s\n",
60a1f02c MR	431	handler[reason], esr, esr_get_class_string(esr));
9955ac47 MR	432	__show_regs(regs);
	433
	434	info.si_signo = SIGILL;
	435	info.si_errno = 0;
	436	info.si_code = ILL_ILLOPC;
	437	info.si_addr = pc;
60ffc30d	438
9955ac47	439	arm64_notify_die("Oops - bad mode", regs, &info, 0);
60ffc30d CM	440	}
	441
	442	void __pte_error(const char *file, int line, unsigned long val)
	443	{
ac7b406c	444	pr_crit("%s:%d: bad pte %016lx.\n", file, line, val);
60ffc30d CM	445	}
	446
	447	void __pmd_error(const char *file, int line, unsigned long val)
	448	{
ac7b406c	449	pr_crit("%s:%d: bad pmd %016lx.\n", file, line, val);
60ffc30d CM	450	}
60ffc30d CM	451
c79b954b JL	452	void __pud_error(const char *file, int line, unsigned long val)
	453	{
	454	pr_crit("%s:%d: bad pud %016lx.\n", file, line, val);
	455	}
	456
60ffc30d CM	457	void __pgd_error(const char *file, int line, unsigned long val)
60ffc30d CM	458	{
ac7b406c	459	pr_crit("%s:%d: bad pgd %016lx.\n", file, line, val);
60ffc30d CM	460	}
	461
	462	void __init trap_init(void)
	463	{
	464	return;
	465	}