Linux 4.13: Reported regressions as of Sunday, 2017-09-03

Hi! Find below my fifth regression report for Linux 4.13. It lists 4
regressions I'm currently aware of. There are no new ones; 2 got fixed
since the last report.

You can also find the report at http://bit.ly/lnxregrep413 where I try
to update it every now and then.

As always: Are you aware of any other regressions? Then please let me
know. For details see http://bit.ly/lnxregtrackid And please tell me if
there is anything in the report that shouldn't be there.

Ciao, Thorsten

P.S.: Thx to all those that CCed me on regression reports or provided
other input, it makes compiling these reports a whole lot easier!

== Current regressions ==

[x86/mm/gup] e585513b76: will-it-scale.per_thread_ops -6.9% regression
Status: Asked on the list, but looks like issue gets ignored by everyone
Note: I'm a bit unsure if adding this issue to this list was a good
idea. Side note: Was reported against linux-next in May already
Reported: 2017-07-10
http://lkml.kernel.org/r/20170710024020.GA26389@yexl-desktop
Cause: https://git.kernel.org/torvalds/c/e585513b76f7

[lkp-robot] [Btrfs] 28785f70ef: xfstests.generic.273.fail
Status: Jeff: "We're not ignoring it. […] collection of bugs that
approximate a correct result, and we're addressing them individually.[…]"
Reported: 2017-07-26 Last known developer activity: 2017-08-10
https://lkml.kernel.org/r/20170726062352.GC4877@yexl-desktop
https://lkml.kernel.org/r/bcd49705-e63a-4439-1620-57cd16f5bc09@suse.com
Cause: https://git.kernel.org/torvalds/c/28785f70ef88
Linux-Regression-ID: lr#a7d273

Build regression: cc1: error: '-march=r3000' requires '-mfp32'
Note: is there any way to query 0-day to see if this is still happening?
Reported: 2017-08-13
https://lkml.org/lkml/2017/8/13/38
Cause: https://git.kernel.org/torvalds/c/89a55278dee4

usb:xhci: regression when ATI chipsets detected
Status: Fix in usb-next/usb-testing
Reported: 2017-08-23 Last known developer activity: 2017-08-28
https://lkml.kernel.org/r/1503485760-15146-1-git-send-email-Sandeep.Singh@amd.com
Cause: https://git.kernel.org/torvalds/c/e788787ef4f9


== Fixed since last report ==

[Dell xps13 9630] Could not be woken up from suspend-to-idle via usb
keyboard
Status: was a tracking bug that got closed by the developer that created it
Reported: 2017-07-24
https://bugzilla.kernel.org/show_bug.cgi?id=196459
Cause: https://git.kernel.org/torvalds/c/33e4f80ee69b
Linux-Regression-ID: lr#bd29ab

CIFS mount error -112 due to "SMB3 by default for security reasons"
Status: Situation not perfect, but improved a lot by
https://git.kernel.org/torvalds/c/7e682f766f28
Note: https://lkml.org/lkml/2017/8/31/843
Reported: 2017-08-06
https://bugzilla.kernel.org/show_bug.cgi?id=196599
Cause: https://git.kernel.org/torvalds/c/eef914a9eb5e /
https://git.kernel.org/torvalds/c/908b852df1d5
Linux-Regression-ID: lr#60efe5

On Sun, Sep 3, 2017 at 2:36 AM, Thorsten Leemhuis
[off-list ref] wrote:

[x86/mm/gup] e585513b76: will-it-scale.per_thread_ops -6.9% regression
Status: Asked on the list, but looks like issue gets ignored by everyone
Note: I'm a bit unsure if adding this issue to this list was a good
idea. Side note: Was reported against linux-next in May already
Reported: 2017-07-10
http://lkml.kernel.org/r/20170710024020.GA26389@yexl-desktop
Cause: https://git.kernel.org/torvalds/c/e585513b76f7

Sadly, while I love the concept of performance tracking, the
"will-it-scale" reports haven't really been reliable enough to really
be useful. There is a _ton_ of noise in the numbers, and the
test-cases don't seem to be stable enough to really track sanely.

I wish it was otherwise, because we also got a report of "57.3%
improvement of will-it-scale.per_process_ops" this release.

So I find the kernel test robot performance tracking very interesting
in theory, but as things stand now I think it's just that:
"interesting". Not quite ready for action.

                 Linus