Re: [PATCH v2] xen-blkfront: allow discard-* nodes to be optional

From: Roger Pau Monné
Date: Wed Jan 20 2021 - 09:37:57 EST

On Wed, Jan 20, 2021 at 03:23:30PM +0100, Arthur Borsboom wrote:
> Hi Roger,
> I have set up a test environment based on Linux 5.11.0-rc4.
> The patch did not apply clean, so I copied/pasted the patch manually.
> Without the patch the call trace (as reported) is visible in dmesg.
> With the patch the call trace in dmesg is gone, but ... (there is always a
> but) ...
> Now the discard action returns the following.
> [arthur@test-arch ~]$ sudo fstrim -v /
> fstrim: /: the discard operation is not supported
> It might be correct, but of course I was hoping the Xen VM guest would pass
> on the discard request to the block device in the Xen VM host, which is a
> disk partition.
> Any suggestions?

Hm, that's not what I did see on my testing, the operation worked OK,
and that's what I would expect to happen in your case also, since I
know the xenstore keys.

I think it's possible your email client has mangled the patch, I'm
attaching the same patch to this email, could you try to apply it
again and report back? (this time it should apply cleanly)

Thanks, Roger.