[ARM] traps: don't call undef hook functions with spinlock held
Calling the undefined instruction handler functions with a
spinlock held is a recipe for must_sleep() warnings. Avoid it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 7277aef..872f1f8 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -288,14 +288,28 @@
spin_unlock_irqrestore(&undef_lock, flags);
}
+static int call_undef_hook(struct pt_regs *regs, unsigned int instr)
+{
+ struct undef_hook *hook;
+ unsigned long flags;
+ int (*fn)(struct pt_regs *regs, unsigned int instr) = NULL;
+
+ spin_lock_irqsave(&undef_lock, flags);
+ list_for_each_entry(hook, &undef_hook, node)
+ if ((instr & hook->instr_mask) == hook->instr_val &&
+ (regs->ARM_cpsr & hook->cpsr_mask) == hook->cpsr_val)
+ fn = hook->fn;
+ spin_unlock_irqrestore(&undef_lock, flags);
+
+ return fn ? fn(regs, instr) : 1;
+}
+
asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
{
unsigned int correction = thumb_mode(regs) ? 2 : 4;
unsigned int instr;
- struct undef_hook *hook;
siginfo_t info;
void __user *pc;
- unsigned long flags;
/*
* According to the ARM ARM, PC is 2 or 4 bytes ahead,
@@ -325,17 +339,8 @@
}
#endif
- spin_lock_irqsave(&undef_lock, flags);
- list_for_each_entry(hook, &undef_hook, node) {
- if ((instr & hook->instr_mask) == hook->instr_val &&
- (regs->ARM_cpsr & hook->cpsr_mask) == hook->cpsr_val) {
- if (hook->fn(regs, instr) == 0) {
- spin_unlock_irqrestore(&undef_lock, flags);
- return;
- }
- }
- }
- spin_unlock_irqrestore(&undef_lock, flags);
+ if (call_undef_hook(regs, instr) == 0)
+ return;
#ifdef CONFIG_DEBUG_USER
if (user_debug & UDBG_UNDEFINED) {