From: Christophe Leroy <christophe.leroy@xxxxxx> commit 099bc4812f09155da77eeb960a983470249c9ce1 upstream. Before commit 0366a1c70b89 ("powerpc/irq: Run softirqs off the top of the irq stack"), check_stack_overflow() was called by do_IRQ(), before switching to the irq stack. In that commit, do_IRQ() was renamed __do_irq(), and is now executing on the irq stack, so check_stack_overflow() has just become almost useless. Move check_stack_overflow() call in do_IRQ() to do the check while still on the current stack. Fixes: 0366a1c70b89 ("powerpc/irq: Run softirqs off the top of the irq stack") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/e033aa8116ab12b7ca9a9c75189ad0741e3b9b5f.1575872340.git.christophe.leroy@xxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/kernel/irq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -527,8 +527,6 @@ void __do_irq(struct pt_regs *regs) trace_irq_entry(regs); - check_stack_overflow(); - /* * Query the platform PIC for the interrupt & ack it. * @@ -560,6 +558,8 @@ void do_IRQ(struct pt_regs *regs) irqtp = hardirq_ctx[raw_smp_processor_id()]; sirqtp = softirq_ctx[raw_smp_processor_id()]; + check_stack_overflow(); + /* Already there ? */ if (unlikely(curtp == irqtp || curtp == sirqtp)) { __do_irq(regs);