3.16.83-rc1 review patch. If anyone has any objections, please let me know.
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From: Christophe Leroy christophe.leroy@c-s.fr
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") Signed-off-by: Christophe Leroy christophe.leroy@c-s.fr Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/e033aa8116ab12b7ca9a9c75189ad0741e3b9b5f.157587234... Signed-off-by: Ben Hutchings ben@decadent.org.uk --- 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 @@ -471,8 +471,6 @@ void __do_irq(struct pt_regs *regs)
trace_irq_entry(regs);
- check_stack_overflow(); - /* * Query the platform PIC for the interrupt & ack it. * @@ -504,6 +502,8 @@ 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);