x86/irq: Do not dereference irq descriptor before checking it
Having the IS_NULL_OR_ERR() check after dereferencing the pointer is
not really working well.
Move the dereference after the check.
Fixes: a782a7e46bb5 'x86/irq: Store irq descriptor in vector array'
Reported-and-tested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index 217b013..c80cf66 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -150,7 +150,7 @@
bool handle_irq(struct irq_desc *desc, struct pt_regs *regs)
{
- unsigned int irq = irq_desc_get_irq(desc);
+ unsigned int irq;
int overflow;
overflow = check_stack_overflow();
@@ -158,6 +158,7 @@
if (IS_ERR_OR_NULL(desc))
return false;
+ irq = irq_desc_get_irq(desc);
if (user_mode(regs) || !execute_on_irq_stack(overflow, desc, irq)) {
if (unlikely(overflow))
print_stack_overflow();