CA-419840 mark CD VBD as empty when its VDI is removed #6840
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Contributor
Author
|
I will also create a PR for a back port |
kc284
approved these changes
Jan 16, 2026
lindig
force-pushed
the
private/christianlin/CA-419840
branch
from
dd22182 to
73bc557
Compare
robhoes
approved these changes
Jan 20, 2026
Member
robhoes
left a comment
robhoes
left a comment
There was a problem hiding this comment.
Just one minor comment, but otherwise looks good.
ocaml/xapi/xapi_vdi.ml
Outdated
| (* CA-419840 mark VBD as empty when it is a CDR *) | ||
| ( Db.VDI.get_VBDs ~__context ~self:vdi |> function | ||
| | [] -> | ||
| warn "%s: no VBD for VDI %s" __FUNCTION__ (Ref.string_of vdi) |
Member
There was a problem hiding this comment.
I think warn will sound too alarming here. This is probably a common case and not a problem at all.
Contributor
Author
There was a problem hiding this comment.
I changed it and rebased.
When a CDR is removed from an ISO SR the corresponding VDI is deleted. So far we relied on the DB GC to mark the VBD as empty. This creates a window for a race where the VDI/CD is reported as present when in fact it is not. So mark the VBD as empty as early as possible. Signed-off-by: Christian Lindig <[email protected]>
lindig
force-pushed
the
private/christianlin/CA-419840
branch
from
73bc557 to
be5420b
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
When a CDR is removed from an ISO SR the corresponding VDI is deleted. So far we relied on the DB GC to mark the VBD as empty. This creates a window for a race where the VDI/CD is reported as present when in fact it is not. So mark the VBD as empty as early as possible.