Re: Regression of v4.6-rc vs. v4.5: Merge tag 'drm-intel-next-2016-02-29'

[Stefan Richter <stefanr@s5r6.in-berlin.de>]

On Apr 29 Stefan Richter wrote:
> On Apr 26 Stefan Richter wrote:
> > v4.6-rc solidly hangs after a short while after boot, login to X11, and
> > doing nothing much remarkable on the just brought up X desktop.
> > 
> > Hardware: x86-64, E3-1245 v3 (Haswell),
> >           mainboard Supermicro X10SAE,
> >           using integrated Intel graphics (HD P4600, i915 driver),
> >           C226 PCH's AHCI and USB 2/3, ASMedia ASM1062 AHCI,
> >           Intel LAN (i217, igb driver),
> >           several IEEE 1394 controllers, some of them behind
> >           PCIe bridges (IDT, PLX) or PCIe-to-PCI bridges (TI, Tundra)
> >           and one PCI-to-CardBus bridge (Ricoh)
> > 
> > kernel.org kernel, Gentoo Linux userland
> > 
> > 1. known good:  v4.5-rc5 (gcc 4.9.3)
> >    known bad:   v4.6-rc2 (gcc 4.9.3), only tried one time
> > 
> > 2. known good:  v4.5.2 (gcc 5.2.0)
> >    known bad:   v4.6-rc5 (gcc 5.2.0), only tried one time
> > 
> > I will send my linux-4.6-rc5/.config in a follow-up message.

 .config: http://www.spinics.net/lists/kernel/msg2243444.html
   lspci: http://www.spinics.net/lists/kernel/msg2243447.html

Some userland package versions, in case these have any bearing:
x11-base/xorg-drivers-1.17
x11-base/xorg-server-1.17.4
x11-bas/xorg-x11-7.4-r2

> After it proved impossible to capture an oops through netconsole, I
> started git bisect.  This will apparently take almost a week, as git
> estimated 13 bisection steps and I will be allowing about 12 hours of
> uptime as a sign for a good kernel.  (In my four or five tests of bad
> kernels before I started bisection, they hung after 3 minutes...5.5 hours
> uptime, with no discernible difference in workload.  Maybe 12 h cutoff is
> even too short...)

There are about 9 more bisection steps left to go.
The first few steps sent me straight into DRM land.
My current "git bisect log" with own annotations:

git bisect start

# bad: [9735a22799b9214d17d3c231fe377fc852f042e9] Linux 4.6-rc2
git bisect bad 9735a22799b9214d17d3c231fe377fc852f042e9

# good: [b562e44f507e863c6792946e4e1b1449fbbac85d] Linux 4.5
git bisect good b562e44f507e863c6792946e4e1b1449fbbac85d

# good: [6b5f04b6cf8ebab9a65d9c0026c650bb2538fd0f] Merge branch 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
# ++ still good after 18 h uptime
git bisect good 6b5f04b6cf8ebab9a65d9c0026c650bb2538fd0f

# good: [2c856e14dad8cb1b085ae1f30c5e125c6d46019b] Merge tag 'arm64-perf' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
# ++ still good after 24 h uptime
git bisect good 2c856e14dad8cb1b085ae1f30c5e125c6d46019b

# bad: [8bb7e27bbb9d0db7ca0e83d40810fb752381cdd5] staging: delete STE RMI4 hackish driver
# -- hung after 3 h uptime
git bisect bad 8bb7e27bbb9d0db7ca0e83d40810fb752381cdd5

# bad: [507d44a9e1bb01661c75b88fd866d2461ab41c9c] Merge tag 'drm-intel-next-2016-02-29' of git://anongit.freedesktop.org/drm-intel into drm-next
# -- hung after 2 h uptime
git bisect bad 507d44a9e1bb01661c75b88fd866d2461ab41c9c
-- 
Stefan Richter
-======----- -=-- ====-
http://arcgraph.de/sr/