From: Babis Chalios <bchalios@amazon.es>
To: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Alexander Graf <graf@amazon.com>, <linux-kernel@vger.kernel.org>,
<stable@vger.kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Theodore Ts'o <tytso@mit.edu>,
"Cali, Marco" <xmarcalx@amazon.co.uk>,
Arnd Bergmann <arnd@arndb.de>,
"rostedt@goodmis.org" <rostedt@goodmis.org>,
"Christian Brauner" <brauner@kernel.org>, <linux@leemhuis.info>,
<regressions@lists.linux.dev>,
Lennart Poettering <mzxreary@0pointer.de>
Subject: Re: [REGRESSION] Re: [PATCH] Revert "vmgenid: emit uevent when VMGENID updates"
Date: Fri, 3 May 2024 12:14:19 +0200 [thread overview]
Message-ID: <9cd37dda-29ea-4a4a-ae43-1cab0449ab0e@amazon.es> (raw)
In-Reply-To: <Zi9ilaX3254KL3Pp@gardel-login>
Hi Jason,
Friendly ping?
IMHO Lennart, Alex and myself have raised (what I think to be) valid
technical points regarding your concerns about your belief that the
uevent mechanism is an ad-hoc mechanism that you don't consider viable.
Just to summarize:
* Upon VM clone, user space needs to adjust various components (DHCP
leases, MAC addresses, etc.) that have nothing to do with PRNGs.
* The path of exposing the VM clone event via vgetrandom() (or any other
interface of random.c) is simply wrong. The random subsystem is the
natural component to inform about when cached entropy is stale. It
should not be responsible for informing user space about VM clone
events. IOW, "reseed your PRNGs" is not equivalent to "your VM has been
cloned".
Given all this, it would help the discussion if you explained why you
believe random.c should propagate VM clone events and how.
If you don't believe that, could you explain what is the problem with
the proposed uevent mechanism? Personally, I agree with Lennart that
VMGenID is a generic ACPI device built for exactly this purpose. VMGenID
is not an "ad-hoc driver". It is a standard which is supported by most
(all?) major VMMs out there today and its whole purpose is to deliver
inside the VM a notification that it was cloned.
Cheers,
Babis
next prev parent reply other threads:[~2024-05-03 10:14 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20240418114814.24601-1-Jason@zx2c4.com>
2024-04-22 7:51 ` [REGRESSION] Re: [PATCH] Revert "vmgenid: emit uevent when VMGENID updates" Alexander Graf
2024-04-23 1:21 ` Jason A. Donenfeld
2024-04-23 6:56 ` Alexander Graf
2024-04-23 12:23 ` Lennart Poettering
2024-04-26 11:33 ` Alexander Graf
2024-04-26 12:52 ` Jason A. Donenfeld
2024-04-26 13:43 ` Babis Chalios
2024-04-26 20:05 ` Alexander Graf
2024-04-29 9:04 ` Lennart Poettering
2024-05-03 10:14 ` Babis Chalios [this message]
2024-04-26 14:20 ` Linux regression tracking (Thorsten Leemhuis)
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=9cd37dda-29ea-4a4a-ae43-1cab0449ab0e@amazon.es \
--to=bchalios@amazon.es \
--cc=Jason@zx2c4.com \
--cc=arnd@arndb.de \
--cc=brauner@kernel.org \
--cc=graf@amazon.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@leemhuis.info \
--cc=mzxreary@0pointer.de \
--cc=regressions@lists.linux.dev \
--cc=rostedt@goodmis.org \
--cc=stable@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=tytso@mit.edu \
--cc=xmarcalx@amazon.co.uk \
/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;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).