This is a note to let you know that I've just added the patch titled powerpc/irq: fix stack overflow verification to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-irq-fix-stack-overflow-verification.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 099bc4812f09155da77eeb960a983470249c9ce1 Mon Sep 17 00:00:00 2001 From: Christophe Leroy <christophe.leroy@xxxxxx> Date: Mon, 9 Dec 2019 06:19:08 +0000 Subject: powerpc/irq: fix stack overflow verification 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 @@ -619,8 +619,6 @@ void __do_irq(struct pt_regs *regs) trace_irq_entry(regs); - check_stack_overflow(); - /* * Query the platform PIC for the interrupt & ack it. * @@ -652,6 +650,8 @@ void do_IRQ(struct pt_regs *regs) irqsp = hardirq_ctx[raw_smp_processor_id()]; sirqsp = softirq_ctx[raw_smp_processor_id()]; + check_stack_overflow(); + /* Already there ? */ if (unlikely(cursp == irqsp || cursp == sirqsp)) { __do_irq(regs); Patches currently in stable-queue which might be from christophe.leroy@xxxxxx are queue-5.4/spi-fsl-don-t-map-irq-during-probe.patch queue-5.4/powerpc-irq-fix-stack-overflow-verification.patch queue-5.4/spi-fsl-use-platform_get_irq-instead-of-of_irq_to_resource.patch