From: Thomas Gleixner tglx@linutronix.de
stable inclusion from linux-4.19.205 commit cab824f67d7e8f68288d615929dec02607e473ad
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commit 826da771291fc25a428e871f9e7fb465e390f852 upstream.
X86 IO/APIC and MSI interrupts (when used without interrupts remapping) require that the affinity setup on startup is done before the interrupt is enabled for the first time as the non-remapped operation mode cannot safely migrate enabled interrupts from arbitrary contexts. Provide a new irq chip flag which allows affected hardware to request this.
This has to be opt-in because there have been reports in the past that some interrupt chips cannot handle affinity setting before startup.
Fixes: 18404756765c ("genirq: Expose default irq affinity mask (take 3)") Signed-off-by: Thomas Gleixner tglx@linutronix.de Tested-by: Marc Zyngier maz@kernel.org Reviewed-by: Marc Zyngier maz@kernel.org Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.779791738@linutronix.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Conflicts: include/linux/irq.h [yyl: adjust context] Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- include/linux/irq.h | 2 ++ kernel/irq/chip.c | 5 ++++- 2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/include/linux/irq.h b/include/linux/irq.h index ca367d98a991e..536f1abc9a8ce 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -554,6 +554,7 @@ struct irq_chip { * IRQCHIP_EOI_THREADED: Chip requires eoi() on unmask in threaded mode * IRQCHIP_SUPPORTS_LEVEL_MSI Chip can provide two doorbells for Level MSIs * IRQCHIP_SUPPORTS_NMI: Chip can deliver NMIs, only for root irqchips + * IRQCHIP_AFFINITY_PRE_STARTUP: Default affinity update before startup */ enum { IRQCHIP_SET_TYPE_MASKED = (1 << 0), @@ -565,6 +566,7 @@ enum { IRQCHIP_EOI_THREADED = (1 << 6), IRQCHIP_SUPPORTS_LEVEL_MSI = (1 << 7), IRQCHIP_SUPPORTS_NMI = (1 << 8), + IRQCHIP_AFFINITY_PRE_STARTUP = (1 << 10), };
#include <linux/irqdesc.h> diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index fc03e7271169d..63a9ad8307e6c 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -265,8 +265,11 @@ int irq_startup(struct irq_desc *desc, bool resend, bool force) } else { switch (__irq_startup_managed(desc, aff, force)) { case IRQ_STARTUP_NORMAL: + if (d->chip->flags & IRQCHIP_AFFINITY_PRE_STARTUP) + irq_setup_affinity(desc); ret = __irq_startup(desc); - irq_setup_affinity(desc); + if (!(d->chip->flags & IRQCHIP_AFFINITY_PRE_STARTUP)) + irq_setup_affinity(desc); break; case IRQ_STARTUP_MANAGED: irq_do_set_affinity(d, aff, false);