Re: [Ksummit-discuss] bug-introducing patches

From: Theodore Y. Ts'o
Date: Fri May 04 2018 - 09:09:52 EST


On Fri, May 04, 2018 at 03:31:17PM +0300, Jani Nikula wrote:
> On Fri, 04 May 2018, David Howells <dhowells@xxxxxxxxxx> wrote:
> > Sasha Levin via Ksummit-discuss wrote:
> >
> >> Cc: stable@xxxxxxxxxxxxxxx # commit-id-of-(2)
>
> This has been documented since
>
> commit 8e9b9362266dd16255473c080d846b13e27247bf
> Author: Sebastian Andrzej Siewior <sebastian@xxxxxxxxxxxxx>
> Date: Sun Dec 6 12:24:31 2009 +0100
>
> Doc/stable rules: add new cherry-pick logic
>
> in v2.6.33 so seems like there should have been enough time to fix the
> tools.

The problem is that it's not being *used* that way. In fact, that
documentation is arguably out of date. When it does get used, it's
used to indicate which kernels the stable patch applies. You have to
go pretty far back before you find that suggested usage. Run:

git log --grep stable@xxxxxxxxxx | grep -i cc: | grep stable | grep \#

and see for yourself. The first couple of hits:

Cc: stable@xxxxxxxxxx # 3.11
Cc: stable@xxxxxxxxxx # 4.8+
Cc: stable@xxxxxxxxxx # 4.8+
Cc: stable@xxxxxxxxxx # 4.13+
Cc: stable@xxxxxxxxxx # 4.8+
Cc: stable@xxxxxxxxxx # 4.13 - together with 890da9cf0983
Cc: stable@xxxxxxxxxx # 4.13
Cc: stable@xxxxxxxxxx # 4.13
Cc: stable@xxxxxxxxxx # v4.8+
Cc: stable@xxxxxxxxxx # v4.10+
Cc: stable@xxxxxxxxxx # v4.10+
Cc: stable@xxxxxxxxxx # v4.10+
Cc: stable@xxxxxxxxxx # reverted commits were marked for stable
Cc: stable@xxxxxxxxxx # for the backport of the original commit
Cc: stable@xxxxxxxxxx # v4.8+

At this point, my suggestion would be to delete the text added by the
above-mentioned commit, and add a new syntax. We're much more willing
to support multiple headers, so something like this:

Stable-prereq: DEADBEEF1234: subsystem: bork bork bork....

With multiple Stable-preeq: lines allowed, where the order is
significant, might be one way to do things.

- Ted