Re: [PATCH] ide: Explicitly poll for BHs on cancel

[Hanna Reitz <hreitz@redhat.com>]

On 05.01.22 12:13, Hanna Reitz wrote:

[...]

> Perhaps for a lack of being aware of all the kinds of tests we have, I
> found it impossible to write a reproducer in any of our current test
> frameworks: From how I understand the issue, to reproduce it, you need
> to issue a TRIM request and immediately cancel it, before
> ide_trim_bh_cb() (scheduled as a BH) can run.
>
> I wanted to do this via qtest, but that does not work, because every
> port I/O operation is done via a qtest command, and QEMU will happily
> poll the main context between each qtest command, which means that you
> cannot cancel an ongoing IDE request before a BH scheduled by it is run.
>
> Therefore, I wrote an x86 boot sector that sets up a no-op TRIM request
> (i.e. one where all TRIM ranges have length 0) and immediately cancels
> it by setting SRST.

I just realized we could, if we really wanted to, add this to the 
iotests’ sample_images directory, and then run it from an iotest...

Hanna