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Diffstat (limited to 'arch/arm64/kernel/traps.c')
-rw-r--r--arch/arm64/kernel/traps.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 12cd34ff35d0..2589ef53973a 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -3,6 +3,7 @@
*
* Copyright (C) 1995-2009 Russell King
* Copyright (C) 2012 ARM Ltd.
+ * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
*
* 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
@@ -256,15 +257,58 @@ void arm64_notify_die(const char *str, struct pt_regs *regs,
die(str, regs, err);
}
+static LIST_HEAD(undef_hook);
+
+void register_undef_hook(struct undef_hook *hook)
+{
+ list_add(&hook->node, &undef_hook);
+}
+
+static int call_undef_hook(struct pt_regs *regs, unsigned int instr)
+{
+ struct undef_hook *hook;
+ int (*fn)(struct pt_regs *regs, unsigned int instr) = NULL;
+
+ 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;
+
+ return fn ? fn(regs, instr) : 1;
+}
+
asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
{
+ u32 instr;
siginfo_t info;
void __user *pc = (void __user *)instruction_pointer(regs);
/* check for AArch32 breakpoint instructions */
if (!aarch32_break_handler(regs))
return;
+ if (user_mode(regs)) {
+ if (compat_thumb_mode(regs)) {
+ if (get_user(instr, (u16 __user *)pc))
+ goto die_sig;
+ if (is_wide_instruction(instr)) {
+ u32 instr2;
+ if (get_user(instr2, (u16 __user *)pc+1))
+ goto die_sig;
+ instr <<= 16;
+ instr |= instr2;
+ }
+ } else if (get_user(instr, (u32 __user *)pc)) {
+ goto die_sig;
+ }
+ } else {
+ /* kernel mode */
+ instr = *((u32 *)pc);
+ }
+
+ if (call_undef_hook(regs, instr) == 0)
+ return;
+die_sig:
if (show_unhandled_signals && unhandled_signal(current, SIGILL) &&
printk_ratelimit()) {
pr_info("%s[%d]: undefined instruction: pc=%p\n",