Re: PCI/kernel msi code vs GIC ITS driver conflict?

From: Marc Zyngier
Date: Thu Sep 05 2019 - 09:50:29 EST


On 05/09/2019 14:26, John Garry wrote:
> On 05/09/2019 12:22, Marc Zyngier wrote:
>> OK, debug was slightly off, but it is interesting that the driver didn't
>> unmap the device, either because it is flagged as shared (with what?) or
>> that additional interrupts are allocated in the lpi_map for this
>> instance.
>>
>> Here's an updated debug patch. Can you please run the same thing again?
>>
>
> As requested:
>
> root@(none)$ echo 0000:74:02.0 > ./sys/bus/pci/drivers/hisi_sas_v3_hw/unbind
>
> <snip>
>
> [ 78.593897] Freed devid 7410 event 0 LPI 0
> [ 78.597990] Freed devid 7410 event 1 LPI 0
> [ 78.602080] Freed devid 7410 event 2 LPI 0
> [ 78.606169] Freed devid 7410 event 3 LPI 0
> [ 78.610253] Freed devid 7410 event 4 LPI 0
> [ 78.614337] Freed devid 7410 event 5 LPI 0
> [ 78.618422] Freed devid 7410 event 6 LPI 0
> [ 78.622506] Freed devid 7410 event 7 LPI 0
> [ 78.626590] Freed devid 7410 event 8 LPI 0
> [ 78.630674] Freed devid 7410 event 9 LPI 0
> [ 78.634758] Freed devid 7410 event 10 LPI 0
> [ 78.638930] Freed devid 7410 event 11 LPI 0
> [ 78.643101] Freed devid 7410 event 12 LPI 0
> [ 78.647272] Freed devid 7410 event 13 LPI 0
> [ 78.651445] Freed devid 7410 event 14 LPI 0
> [ 78.655616] Freed devid 7410 event 15 LPI 0
> [ 78.659787] Freed devid 7410 event 16 LPI 0
> [ 78.663959] Unmap devid 7410 shared 0 lpi_map 17-31

Bah. Try this for size...

M.

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 1b5c3672aea2..c3a8d732805f 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -2641,14 +2641,13 @@ static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
struct its_node *its = its_dev->its;
int i;

+ bitmap_release_region(its_dev->event_map.lpi_map,
+ its_get_event_id(irq_domain_get_irq_data(domain, virq)),
+ get_count_order(nr_irqs));
+
for (i = 0; i < nr_irqs; i++) {
struct irq_data *data = irq_domain_get_irq_data(domain,
virq + i);
- u32 event = its_get_event_id(data);
-
- /* Mark interrupt index as unused */
- clear_bit(event, its_dev->event_map.lpi_map);
-
/* Nuke the entry in the domain */
irq_domain_reset_irq_data(data);
}


--
Jazz is not dead, it just smells funny...