[Devel] [PATCH hci-8.1 v9 04/10] dm-qcow2: complete wbd before ending the data qio

[Alexander Ivanov]

Rewrote.

On 11/3/26 18:50, Konstantin Khorenko wrote:
> I won't apply this version, please send v10 with the changes below.
>
> On 10/28/26 16:06, Alexander Ivanov wrote:
>> running in AIO completion context. revert_l_entries_update() then
>> marks clusters unused and dirties R2 after the flush, and the change
>> is never written back.
> - Say what happens to that R2 page instead of "never written back".
>
> The page is dirty and sits on slow_wb_batch_list. Preresume frees all
> md pages in qcow2_free_md_pages_all(), which does not take them off
> that list, so the slow writeback timer can later walk a freed page. If
> the timer comes first, it writes the page after postsuspend, behind the
> flush. Both are worse than a lost update, and the message should say
> which one you are fixing.
>