Re: 'power well on' trace in Linus current tree.

From: Daniel Vetter <daniel@ffwll.ch>
To: Paulo Zanoni <przanoni@gmail.com>
Cc: Dave Jones <davej@redhat.com>,
	Intel Graphics Development <intel-gfx@lists.freedesktop.org>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	Daniel Vetter <daniel.vetter@ffwll.ch>
Subject: Re: 'power well on' trace in Linus current tree.
Date: Fri, 13 Dec 2013 18:46:45 +0100	[thread overview]
Message-ID: <20131213174645.GB9804@phenom.ffwll.local> (raw)
In-Reply-To: <CA+gsUGSuBBHrBi5wUoJ_XqAzJjGjLRA0hf-4+5TTx=OsxVCijQ@mail.gmail.com>

On Fri, Dec 13, 2013 at 03:37:07PM -0200, Paulo Zanoni wrote:
> Hi
> 
> 2013/12/13 Dave Jones <davej@redhat.com>:
> > I left this on overnight, and this morning this was in the log.
> >
> >         Dave
> >
> > WARNING: CPU: 1 PID: 131 at drivers/gpu/drm/i915/intel_display.c:6309 hsw_enable_pc8_work+0x6a9/0x6d0()
> > Power well on
> > Modules linked in: tun hidp bnep rfcomm can_raw can_bcm caif_socket caif phonet af_rxrpc bluetooth can llc2 pppoe pppox ppp_generic slhc af_key rose netrom snd_seq_dummy ipt_ULOG nfnetlink nfc af_802154 irda crc_ccitt rds scsi_transport_iscsi x25 atm appletalk ipx p8023 psnap p8022 llc ax25 cfg80211 rfkill snd_hda_codec_hdmi xfs snd_hda_codec_realtek snd_hda_intel snd_hda_codec coretemp snd_hwdep hwmon snd_seq snd_seq_device x86_pkg_temp_thermal snd_pcm libcrc32c snd_page_alloc e1000e snd_timer snd kvm_intel kvm crct10dif_pclmul crc32c_intel ghash_clmulni_intel shpchp serio_raw pcspkr ptp usb_debug soundcore microcode pps_core
> > CPU: 1 PID: 131 Comm: kworker/1:2 Not tainted 3.13.0-rc3+ #3
> > Workqueue: events hsw_enable_pc8_work
> >  ffffffff81a98b80 ffff88023d185c98 ffffffff8174cfd8 ffff88023d185ce0
> >  ffff88023d185cd0 ffffffff8105414d ffff88023e28d5f8 ffff88023e288000
> >  ffff88024155ef50 ffff88024155ef58 0000000000000080 ffff88023d185d30
> > Call Trace:
> >  [<ffffffff8174cfd8>] dump_stack+0x4e/0x7a
> >  [<ffffffff8105414d>] warn_slowpath_common+0x7d/0xa0
> >  [<ffffffff810541bc>] warn_slowpath_fmt+0x4c/0x50
> >  [<ffffffff81493339>] hsw_enable_pc8_work+0x6a9/0x6d0
> >  [<ffffffff81076611>] process_one_work+0x211/0x6f0
> >  [<ffffffff810765a5>] ? process_one_work+0x1a5/0x6f0
> >  [<ffffffff81076c0b>] worker_thread+0x11b/0x3a0
> >  [<ffffffff81076af0>] ? process_one_work+0x6f0/0x6f0
> >  [<ffffffff8107f55f>] kthread+0xff/0x120
> >  [<ffffffff8107f460>] ? insert_kthread_work+0x80/0x80
> >  [<ffffffff817608ac>] ret_from_fork+0x7c/0xb0
> >  [<ffffffff8107f460>] ? insert_kthread_work+0x80/0x80
> > ---[ end trace 23d69c0f014b7eb8 ]---
> 
> It looks like we need "drm/i915: get a PC8 reference when enabling the
> power well" in -fixes instead of -next. For completeness, we should
> probably also move "drm/i915: change CRTC assertion on LCPLL disable"
> to -fixes. My bad, I forgot to tag them as patches for -fixes. Or we
> could just disable PC8 by default. Daniel, how do you want to proceed?
> 
> The mentioned patches:
> 
> http://cgit.freedesktop.org/~danvet/drm-intel/commit/?h=drm-intel-next-queued&id=d62292c8f778772d1b6ec125d461c8c16fdc0417

This one here doesn't really apply on -fixes due to Imre's power well
rework. Care to send a rebased version?

> http://cgit.freedesktop.org/~danvet/drm-intel/commit/?h=drm-intel-next-queued&id=798183c54799fbe1e5a5bfabb3a8c0505ffd2149

I've tentatively moved this one to my -fixes queue, it's benign enough.

Thanks, Daniel
> 
> 
> >
> >
> > 00:02.0 8086:0412 VGA compatible controller: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller (rev 06)
> >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx@lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> 
> 
> -- 
> Paulo Zanoni

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch