On Mon, Dec 22, 2025 at 5:13 PM Arnd Bergmann <[email protected]> wrote: > > 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.
Ack. > > @@ -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(). This is pretty much just copied from in_intr which also uses _irqsave. I think it makes sense to stick to that for consistency's sake. What do you think?
