[PATCH AUTOSEL 5.15 16/27] vhost_vdpa: don't setup irq offloading when irq_num < 0

From: Sasha Levin
Date: Wed Apr 06 2022 - 21:32:03 EST


From: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>

[ Upstream commit cce0ab2b2a39072d81f98017f7b076f3410ef740 ]

When irq number is negative(e.g., -EINVAL), the virtqueue
may be disabled or the virtqueues are sharing a device irq.
In such case, we should not setup irq offloading for a virtqueue.

Signed-off-by: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
Link: https://lore.kernel.org/r/20220222115428.998334-3-lingshan.zhu@xxxxxxxxx
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/vhost/vdpa.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index d62f05d056b7..299a99532618 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -97,8 +97,11 @@ static void vhost_vdpa_setup_vq_irq(struct vhost_vdpa *v, u16 qid)
return;

irq = ops->get_vq_irq(vdpa, qid);
+ if (irq < 0)
+ return;
+
irq_bypass_unregister_producer(&vq->call_ctx.producer);
- if (!vq->call_ctx.ctx || irq < 0)
+ if (!vq->call_ctx.ctx)
return;

vq->call_ctx.producer.token = vq->call_ctx.ctx;
--
2.35.1