On Mon, Dec 22, 2025, at 17:04, Lorenz Bauer wrote:
> --- a/drivers/char/virtio_console.c
> +++ b/drivers/char/virtio_console.c
> @@ -971,10 +971,17 @@ static __poll_t port_fops_poll(struct file *filp,
> poll_table *wait)
> return EPOLLHUP;
> }
> ret = 0;
> - if (!will_read_block(port))
> +
> + spin_lock(&port->inbuf_lock);
> + if (port->inbuf)
As far as I can tell, you got the interrupt flag handling wrong
in both places: port_fops_poll() is called with interrupts
enabled, so you have to use spin_lock_irq() to block the
interrupt from hanging.
> @@ -1705,6 +1713,10 @@ static void out_intr(struct virtqueue *vq)
> return;
> }
>
> + spin_lock_irqsave(&port->outvq_lock, flags);
> + reclaim_consumed_buffers(port);
> + spin_unlock_irqrestore(&port->outvq_lock, flags);
> +
> wake_up_interruptible(&port->waitqueue);
The callback seems to always be called with interrupts
disabled(), so here it's safe to use spin_lock() instead
of spin_lock_irqsave().
Arnd
