Re: [PATCH 6.7 001/162] btrfs: fix deadlock with fiemap and extent locking

Filipe Manana
2024-03-11T20:07:09Z

On Mon, Mar 11, 2024 at 7:23 PM Linux regression tracking (Thorsten
Leemhuis) <regressions@leemhuis.info> wrote:
>
> On 11.03.24 19:41, David Sterba wrote:
> > On Mon, Mar 11, 2024 at 10:15:31AM +0100, Linux regression tracking (Thorsten Leemhuis) wrote:
> >> On 06.03.24 13:39, Filipe Manana wrote:
> >>> On Mon, Mar 4, 2024 at 9:26 PM Greg Kroah-Hartman
> >>> <gregkh@linuxfoundation.org> wrote:
> >>>>
> >>>> 6.7-stable review patch. If anyone has any objections, please let me know.
> >>>
> >>> It would be better to delay the backport of this patch (and the
> >>> followup fix) to any stable release, because it introduced another
> >>> regression for which there is a reviewed fix but it's not yet in
> >>> Linus' tree:
> >>>
> >>> https://lore.kernel.org/linux-btrfs/cover.1709202499.git.fdmanana@suse.com/
> >>
> >> Those two missed 6.8 afaics. Will those be heading to mainline any time
> >> soon?
> >
> > Yes, in the 6.9 pull request.
>
> Great!
>
> >> And how fast afterwards will it be wise to backport them to 6.8?
> >> Will anyone ask Greg for that when the time has come?
> > The commits have stable tags and will be processed in the usual way.
>
> I'm missing something. The first change from Filipe's series linked
> above has a fixes tag, but no stable tag afaics:
> https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git/commit/?h=for-6.9&id=978b63f7464abcfd364a6c95f734282c50f3decf

It has no stable tag because when I sent the patch there was yet no
kernel release with the buggy commit, which landed in 6.8-rc6.
Now it would make sense to add the stable tag because 6.8 was released
yesterday and it's the first release with the buggy commit.

>
> So there is no guarantee that Greg will pick it up; and I assume if he
> does he only will do so after -rc1 (or later, if the CVE stuff continues
> to keep him busy).

Don't worry, we are paying attention to that and we'll remind Greg if necessary.

> As Filipe wrote "can actually have serious
> consequences" this got me slightly worried. That's why I'm a PITA here,
> sorry -- but as I said, maybe I'm missing something.
>
> The second of the patches has none of those tags, but well, from the
> patch descriptions it seems that is just a optimization, so that is
> likely not something to worry about:
> https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git/commit/?h=for-6.9&id=1cab1375ba6d5337a25acb346996106c12bb2dd0

Yes, it's an optimization. If it were a bug fix, I would have added a
Fixes tag and would have described what the bug was.

>
> Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
> --
> Everything you wanna know about Linux kernel regression tracking:
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> If I did something stupid, please tell me, as explained on that page.
>