From: Cornelia Huck <cohuck@redhat.com>
Sent: 27 August 2025 05:04 PM

On Wed, Aug 27 2025, "Michael S. Tsirkin" [off-list ref] wrote:

quoted

On Tue, Aug 26, 2025 at 06:52:03PM +0000, Parav Pandit wrote:

quoted

quoted

What I do not understand, is what good does the revert do. Sorry.

Let me explain.
It prevents the issue of vblk requests being stuck due to broken VQ.
It prevents the vnet driver start_xmit() to be not stuck on skb completions.

This is the part I don't get.  In what scenario, before 43bb40c5b9265
start_xmit is not stuck, but after 43bb40c5b9265 it is stuck?

Once the device is gone, it is not using any buffers at all.

What I also don't understand: virtio-ccw does exactly the same thing
(virtio_break_device(), added in 2014), and it supports surprise removal
_only_, yet I don't remember seeing bug reports?

I suspect that stress testing may not have happened for ccw with active vblk Ios and outstanding transmit pkt and cvq commands.
Hard to say as we don't have ccw hw or systems.