public inbox for pve-devel@lists.proxmox.com
 help / color / mirror / Atom feed
From: Fiona Ebner <f.ebner@proxmox.com>
To: "Proxmox VE development discussion" <pve-devel@lists.proxmox.com>,
	"Fabian Grünbichler" <f.gruenbichler@proxmox.com>
Subject: Re: [pve-devel] [PATCH qemu-server 1/3] api: clone: always do a full clone of tpmstate volumes
Date: Thu, 12 Dec 2024 10:11:23 +0100	[thread overview]
Message-ID: <b81bd6f2-82a5-4fdb-84f8-d2833c0c6322@proxmox.com> (raw)
In-Reply-To: <20241212085149.138679-2-f.gruenbichler@proxmox.com>

Am 12.12.24 um 09:51 schrieb Fabian Grünbichler:
> since there is no reliable way to check whether a linked clone would end up
> being something other than a raw file, and the volumes are tiny anyway.
> 
> otherwise on directory storages, the following sequence of events could happen:
> - linked clone using raw file as base and qcow2 as overlay
> - swtpm_setup interprets qcow2 file as raw
> - swtpm_setup fails to find TPM state and overwrites it with a new one
> - file is now no longer a linked clone, but a raw file with a qcow2 extension
> - move disk and migration fail because of the format mismatch
> 
> the downside is that storages that actually support raw linked clones (ZFS,
> RBD, LVM-thin) now use more space for fully cloned TPM state volumes...
> 
> Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>

Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>

> ---
> if we want to avoid the downside, I guess we could do the linked clone, if that
> is not raw, remove it again, and then fallback to full clone?
> 

I prefer the approach in the patch. IMHO, the tpmstate is so small that
it doesn't matter.


_______________________________________________
pve-devel mailing list
pve-devel@lists.proxmox.com
https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel

  reply	other threads:[~2024-12-12  9:11 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-12-12  8:51 [pve-devel] [PATCH qemu-server 0/3] fix tpmstate format issues Fabian Grünbichler
2024-12-12  8:51 ` [pve-devel] [PATCH qemu-server 1/3] api: clone: always do a full clone of tpmstate volumes Fabian Grünbichler
2024-12-12  9:11   ` Fiona Ebner [this message]
2024-12-12  8:51 ` [pve-devel] [PATCH qemu-server 2/3] swtpm: check that format of tpmstate volume is raw Fabian Grünbichler
2024-12-12  9:11   ` Fiona Ebner
2024-12-12  9:13     ` Fiona Ebner
2024-12-12  8:51 ` [pve-devel] [PATCH qemu-server 3/3] swtpm: drop unused $volname variable Fabian Grünbichler
2024-12-12  9:11   ` Fiona Ebner
2024-12-12  9:48 ` [pve-devel] applied-series: [PATCH qemu-server 0/3] fix tpmstate format issues Fabian Grünbichler

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=b81bd6f2-82a5-4fdb-84f8-d2833c0c6322@proxmox.com \
    --to=f.ebner@proxmox.com \
    --cc=f.gruenbichler@proxmox.com \
    --cc=pve-devel@lists.proxmox.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Service provided by Proxmox Server Solutions GmbH | Privacy | Legal