This is a note to let you know that I've just added the patch titled MIPS: BMIPS: Do not mask IPIs during suspend to the 4.4-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: mips-bmips-do-not-mask-ipis-during-suspend.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 06a3f0c9f2725f5d7c63c4203839373c9bd00c28 Mon Sep 17 00:00:00 2001 From: Justin Chen <justinpopo6@xxxxxxxxx> Date: Wed, 27 Sep 2017 17:15:15 -0700 Subject: MIPS: BMIPS: Do not mask IPIs during suspend From: Justin Chen <justinpopo6@xxxxxxxxx> commit 06a3f0c9f2725f5d7c63c4203839373c9bd00c28 upstream. Commit a3e6c1eff548 ("MIPS: IRQ: Fix disable_irq on CPU IRQs") fixes an issue where disable_irq did not actually disable the irq. The bug caused our IPIs to not be disabled, which actually is the correct behavior. With the addition of commit a3e6c1eff548 ("MIPS: IRQ: Fix disable_irq on CPU IRQs"), the IPIs were getting disabled going into suspend, thus schedule_ipi() was not being called. This caused deadlocks where schedulable task were not being scheduled and other cpus were waiting for them to do something. Add the IRQF_NO_SUSPEND flag so an irq_disable will not be called on the IPIs during suspend. Signed-off-by: Justin Chen <justinpopo6@xxxxxxxxx> Fixes: a3e6c1eff548 ("MIPS: IRQ: Fix disabled_irq on CPU IRQs") Cc: Florian Fainelli <f.fainelli@xxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Patchwork: https://patchwork.linux-mips.org/patch/17385/ [jhogan@xxxxxxxxxx: checkpatch: wrap long lines and fix commit refs] Signed-off-by: James Hogan <jhogan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/mips/kernel/smp-bmips.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/mips/kernel/smp-bmips.c +++ b/arch/mips/kernel/smp-bmips.c @@ -166,11 +166,11 @@ static void bmips_prepare_cpus(unsigned return; } - if (request_irq(IPI0_IRQ, bmips_ipi_interrupt, IRQF_PERCPU, - "smp_ipi0", NULL)) + if (request_irq(IPI0_IRQ, bmips_ipi_interrupt, + IRQF_PERCPU | IRQF_NO_SUSPEND, "smp_ipi0", NULL)) panic("Can't request IPI0 interrupt"); - if (request_irq(IPI1_IRQ, bmips_ipi_interrupt, IRQF_PERCPU, - "smp_ipi1", NULL)) + if (request_irq(IPI1_IRQ, bmips_ipi_interrupt, + IRQF_PERCPU | IRQF_NO_SUSPEND, "smp_ipi1", NULL)) panic("Can't request IPI1 interrupt"); } Patches currently in stable-queue which might be from justinpopo6@xxxxxxxxx are queue-4.4/mips-bmips-do-not-mask-ipis-during-suspend.patch