linux-kernel - Problem with VirtIO TRIM/DISCARD?

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Message-ID: <CA+osTZWkMh-HOQkLoHNyQLsUusU4N2vY-dr2Z+u7oY63+9o0-Q@mail.gmail.com>
Date:   Fri, 24 Sep 2021 14:22:17 -0700
From:   Jeppe Øland <joland@...il.com>
To:     linux-kernel@...r.kernel.org
Subject: Problem with VirtIO TRIM/DISCARD?

I'm experimenting with running VMs on a 4Kn sector array, but I'm
having some issues.
Specifically it seems VirtIO TRIM/DISCARD support may be broken for
non 512B sector sizes.

I started digging, and landed on this commit:
https://github.com/torvalds/linux/commit/af822aa68fbdf0a480a17462ed70232998127453

On line 143 the TRIM/DISCARD size is converted to a sector count - but
it's using a hardcoded sector size of 512.
Shouldn't that be using the actual block size gotten earlier?

Did that code just wipe out a ton of data following the TRIM/DISCARD area?

Regards,
-Jeppe