Messages in this thread Patch in this message | | | From | Marc Zyngier <> | Subject | [PATCH] genirq/msi: Shutdown managed interrupts with unsatifiable affinities | Date | Mon, 7 Mar 2022 19:06:25 +0000 |
| |
When booting with maxcpus=<small number>, interrupt controllers such as the GICv3 ITS may not be able to satisfy the affinity of some managed interrupts, as some of the HW resources are simply not available.
In order to deal with this, do not try to activate such interrupt if there is no online CPU capable of handling it. Instead, place it in shutdown state. Once a capable CPU shows up, it will be activated.
Reported-by: John Garry <john.garry@huawei.com> Reported-by: David Decotigny <ddecotig@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> --- kernel/irq/msi.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index 2bdfce5edafd..aa84ce84c2ec 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -818,6 +818,18 @@ static int msi_init_virq(struct irq_domain *domain, int virq, unsigned int vflag irqd_clr_can_reserve(irqd); if (vflags & VIRQ_NOMASK_QUIRK) irqd_set_msi_nomask_quirk(irqd); + + /* + * If the interrupt is managed but no CPU is available + * to service it, shut it down until better times. + */ + if ((vflags & VIRQ_ACTIVATE) && + irqd_affinity_is_managed(irqd) && + !cpumask_intersects(irq_data_get_affinity_mask(irqd), + cpu_online_mask)) { + irqd_set_managed_shutdown(irqd); + return 0; + } } if (!(vflags & VIRQ_ACTIVATE)) -- 2.30.2
| |