[PATCH 5.0 55/93] irqchip/mbigen: Dont clear eventid when freeing an MSI

From: Greg Kroah-Hartman
Date: Thu Apr 18 2019 - 14:17:10 EST


[ Upstream commit fca269f201a8d9985c0a31fb60b15d4eb57cef80 ]

mbigen_write_msg clears eventid bits of a mbigen register
when free a interrupt, because msi_domain_deactivate memset
struct msg to zero. Then multiple mbigen pins with zero eventid
will report the same interrupt number.

The eventid clear call trace:
free_irq
__free_irq
irq_shutdown
irq_domain_deactivate_irq
__irq_domain_deactivate_irq
__irq_domain_deactivate_irq
msi_domain_deactivate
platform_msi_write_msg
mbigen_write_msg

Signed-off-by: Jianguo Chen <chenjianguo3@xxxxxxxxxx>
[maz: massaged subject]
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/irqchip/irq-mbigen.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/irqchip/irq-mbigen.c b/drivers/irqchip/irq-mbigen.c
index 567b29c47608..98b6e1d4b1a6 100644
--- a/drivers/irqchip/irq-mbigen.c
+++ b/drivers/irqchip/irq-mbigen.c
@@ -161,6 +161,9 @@ static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
void __iomem *base = d->chip_data;
u32 val;

+ if (!msg->address_lo && !msg->address_hi)
+ return;
+
base += get_mbigen_vec_reg(d->hwirq);
val = readl_relaxed(base);

--
2.19.1