Re: [REGRESSION] Chrome and VSCode breakage with the commit b9b588f22a0c

Greg KH
2025-02-26T16:19:47Z

On Wed, Feb 26, 2025 at 10:56:46AM -0500, Chuck Lever wrote:
> On 2/26/25 9:26 AM, Greg KH wrote:
> > On Wed, Feb 26, 2025 at 09:20:20AM -0500, Chuck Lever wrote:
> >> On 2/26/25 9:16 AM, Takashi Iwai wrote:
> >>> On Wed, 26 Feb 2025 15:11:04 +0100,
> >>> Chuck Lever wrote:
> >>>>
> >>>> On 2/26/25 3:38 AM, Takashi Iwai wrote:
> >>>>> On Sun, 23 Feb 2025 16:18:41 +0100,
> >>>>> Chuck Lever wrote:
> >>>>>>
> >>>>>> On 2/23/25 3:53 AM, Takashi Iwai wrote:
> >>>>>>> [ resent due to a wrong address for regression reporting, sorry! ]
> >>>>>>>
> >>>>>>> Hi,
> >>>>>>>
> >>>>>>> we received a bug report showing the regression on 6.13.1 kernel
> >>>>>>> against 6.13.0. The symptom is that Chrome and VSCode stopped working
> >>>>>>> with Gnome Scaling, as reported on openSUSE Tumbleweed bug tracker
> >>>>>>> https://bugzilla.suse.com/show_bug.cgi?id=1236943
> >>>>>>>
> >>>>>>> Quoting from there:
> >>>>>>> """
> >>>>>>> I use the latest TW on Gnome with a 4K display and 150%
> >>>>>>> scaling. Everything has been working fine, but recently both Chrome
> >>>>>>> and VSCode (installed from official non-openSUSE channels) stopped
> >>>>>>> working with Scaling.
> >>>>>>> ....
> >>>>>>> I am using VSCode with:
> >>>>>>> `--enable-features=UseOzonePlatform --enable-features=WaylandWindowDecorations --ozone-platform-hint=auto` and for Chrome, I select `Preferred Ozone platform` == `Wayland`.
> >>>>>>> """
> >>>>>>>
> >>>>>>> Surprisingly, the bisection pointed to the backport of the commit
> >>>>>>> b9b588f22a0c049a14885399e27625635ae6ef91 ("libfs: Use d_children list
> >>>>>>> to iterate simple_offset directories").
> >>>>>>>
> >>>>>>> Indeed, the revert of this patch on the latest 6.13.4 was confirmed to
> >>>>>>> fix the issue. Also, the reporter verified that the latest 6.14-rc
> >>>>>>> release is still affected, too.
> >>>>>>>
> >>>>>>> For now I have no concrete idea how the patch could break the behavior
> >>>>>>> of a graphical application like the above. Let us know if you need
> >>>>>>> something for debugging. (Or at easiest, join to the bugzilla entry
> >>>>>>> and ask there; or open another bug report at whatever you like.)
> >>>>>>>
> >>>>>>> BTW, I'll be traveling tomorrow, so my reply will be delayed.
> >>>>>>>
> >>>>>>>
> >>>>>>> thanks,
> >>>>>>>
> >>>>>>> Takashi
> >>>>>>>
> >>>>>>> #regzbot introduced: b9b588f22a0c049a14885399e27625635ae6ef91
> >>>>>>> #regzbot monitor: https://bugzilla.suse.com/show_bug.cgi?id=1236943
> >>>>>>
> >>>>>> We received a similar report a few days ago, and are likewise puzzled at
> >>>>>> the commit result. Please report this issue to the Chrome development
> >>>>>> team and have them come up with a simple reproducer that I can try in my
> >>>>>> own lab. I'm sure they can quickly get to the bottom of the application
> >>>>>> stack to identify the misbehaving interaction between OS and app.
> >>>>>
> >>>>> Do you know where to report to?
> >>>>
> >>>> You'll need to drive this, since you currently have a working
> >>>> reproducer.
> >>>
> >>> No, I don't have, I'm merely a messenger.
> >>
> >> Whoever was the original reporter has the ability to reproduce this and
> >> answer any questions the Chrome team might have. Please have them drive
> >> this. I'm already two steps removed, so it doesn't make sense for me to
> >> report a problem for which I have no standing.
> >
> > Ugh, no. The bug was explictly bisected to the offending commit. We
> > should just revert that commit for now and it can come back in the
> > future if the root-cause is found.
> >
> > As the revert seems to be simple, and builds here for me, I guess I'll
> > have to send it in. {sigh}
>
> Note that reverting also reintroduces a CVE.

That's fine, regressions are more important :)