Re: [PATCH v1 0/4] virtio-mem: memory unplug/offlining related cleanups

Michael S. Tsirkin
2023-07-13T15:04:11Z

On Thu, Jul 13, 2023 at 04:55:47PM +0200, David Hildenbrand wrote:
> Some cleanups+optimizations primarily around offline_and_remove_memory().
>
> Patch #1 drops the "unsafe unplug" feature where we might get stuck in
> offline_and_remove_memory() forever.
>
> Patch #2 handles unexpected errors from offline_and_remove_memory() a bit
> nicer.
>
> Patch #3 handles the case where offline_and_remove_memory() failed and
> we want to retry later to remove a completely unplugged Linux memory
> block, to not have them waste memory forever.
>
> Patch #4 something I had lying around for longer, which reacts faster
> on config changes when unplugging memory.
>
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Cc: Jason Wang <jasowang@redhat.com>
> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>

This looks like something that's reasonable to put in this linux, right?
These are fixes even though they are for theoretical issues.

> David Hildenbrand (4):
> virtio-mem: remove unsafe unplug in Big Block Mode (BBM)
> virtio-mem: convert most offline_and_remove_memory() errors to -EBUSY
> virtio-mem: keep retrying on offline_and_remove_memory() errors in Sub
> Block Mode (SBM)
> virtio-mem: check if the config changed before fake offlining memory
>
> drivers/virtio/virtio_mem.c | 168 ++++++++++++++++++++++++------------
> 1 file changed, 112 insertions(+), 56 deletions(-)
>
>
> base-commit: 3f01e9fed8454dcd89727016c3e5b2fbb8f8e50c
> --
> 2.41.0