On 3/29/25 8:17 AM, Takashi Iwai wrote: > On Sun, 23 Feb 2025 09:53:10 +0100, > 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 > > After all, this seems to be a bug in Chrome and its variant, which was > surfaced by the kernel commit above: as the commit changes the > directory enumeration, it also changed the list order returned from > libdrm drmGetDevices2(), and it screwed up the application that worked > casually beforehand. That said, the bug itself has been already > present. The Chrome upstream tracker: > https://issuetracker.google.com/issues/396434686 > > #regzbot invalid: problem has always existed on Chrome and related code > > > Takashi Thank you very much for your report and for chasing this to conclusion. -- Chuck Lever
