| Message ID | CA+55aFzsVMMpSeF3fG0FJ4Lhj1Tb6MY9LMfnmj7u1JyzM9aQuA@mail.gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 30 July 2015 at 15:18, Linus Torvalds <torvalds@linux-foundation.org> wrote: > On Wed, Jul 29, 2015 at 6:39 PM, Theodore Ts'o <tytso@mit.edu> wrote: >> >> It's here: https://goo.gl/photos/xHjn2Z97JQEw6k2C9 > > You didn't catch enough of the code line to decode the code, but it's > early enough in drm_crtc_index() (just five bytes in) that it's almost > certainly the very first dereference, so it's almost guaranteed to be > that > > crtc->dev > > access as part of list_for_each_entry(), with crtc being NULL. And > yes, "->dev" is the very first field, so the offset is zero too (while > the "->mode_config" list access would not be at offset zero). > > And it looks like it is called from drm_atomic_helper_check_modeset(): > the reason it has a question mark in the backtrace is because the > fault happens before the stack frame has even been set up. > > There are multiple calls to "drm_crtc_index()" from that function, I > can't tell which one it is. Looking at the code generation I get, I > think it's because update_connector_routing() gets inlined, and that > one does several calls. Most of them look like this: > > if (connector->state->crtc) { > idx = drm_crtc_index(connector->state->crtc); > > ie they check that the crtc is non-NULL, but that last one does not: > > connector_state->best_encoder = new_encoder; > idx = drm_crtc_index(connector_state->crtc); > > crtc_state = state->crtc_states[idx]; > crtc_state->mode_changed = true; > > and I suspect the fix might be something like the attached. Totally > untested. Ted? > > This whole "atomic modeset" series has been one royal fuck-up, guys. > We've had too many of these kinds of crap issues. It hasn't been that bad, on a scale of 1 to MD eats my raid array, I'd say we are barely at a 5. There have been a lot of small and seemingly easily fixed teething problems, essentially rewriting the DRM API to provide a new userspace API and internal interface, porting some drivers partly to the new interface, while trying to maintain the old ABI/API on top seamlessly was always going to be an impossible task. It was never going to magically all just work in -next and land in your tree fully formed smelling of lavender and elderberries. This is a massive undertaking, and doing it over a few kernels was the only possible way it could ever land. I think the biggest problem we've had is the QA team at Intel got reorganised or something right when they really needed to be doing testing on this stuff, so what was sitting in -next never got as much testing as it had previously, and you can see that in the types of cases that are getting through. I think the other thing we can learn is that when Android forks the kernel we should just say this shit is too hard, let Google go and create a new API and a complete set of graphics drivers and deal with it in 10 years, because that was seriously the only other option. So yes it's a pity other kernel developers are seeing our fallout, but I've experienced lots of other kernel developers fall out over the years, and generally the idea is to get this stuff fixed to a reasonable state before you release a final kernel. Note I'm not personally involved in the development for atomic modesetting at all, I'm running the kernels with it where and when I can, and I trust the developers who work on it are doing as much as they can to make it work. That said hopefully Daniel can find a bag of fucks to debug and write a proper patch, instead of rage quitting the universe, and just git reset --hard v4.0 drivers/gpu/drm/i915.. Dave.
On Wed, Jul 29, 2015 at 10:18:16PM -0700, Linus Torvalds wrote: > drivers/gpu/drm/drm_atomic_helper.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > index 5b59d5ad7d1c..aac212297b49 100644 > --- a/drivers/gpu/drm/drm_atomic_helper.c > +++ b/drivers/gpu/drm/drm_atomic_helper.c > @@ -230,10 +230,12 @@ update_connector_routing(struct drm_atomic_state *state, int conn_idx) > } > > connector_state->best_encoder = new_encoder; > - idx = drm_crtc_index(connector_state->crtc); > + if (connector_state->crtc) { > + idx = drm_crtc_index(connector_state->crtc); > > - crtc_state = state->crtc_states[idx]; > - crtc_state->mode_changed = true; > + crtc_state = state->crtc_states[idx]; > + crtc_state->mode_changed = true; > + } This shouldn't happen since if it does we ended up stealing the encoder from the connector itself (we do check for connector_state->crtc earlier) and that would be a bug. I haven't figured out a precise theory but my guess is on the best_encoder selection, and indeed dp mst encoder selection seems to have gone belly up in 4.2 with the bisected commit. I have 4 patches in git://people.freedesktop.org/~danvet/drm fixes-stuff but I couldn't test them yet since no dp mst here and I didn't find anything that would ship faster than 1-2 weeks yet. I'll try to get some other people here to test it meanwhile too. -Daniel
On Thu, Jul 30, 2015 at 04:40:02PM +0200, Daniel Vetter wrote: > On Wed, Jul 29, 2015 at 10:18:16PM -0700, Linus Torvalds wrote: > > drivers/gpu/drm/drm_atomic_helper.c | 8 +++++--- > > 1 file changed, 5 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > > index 5b59d5ad7d1c..aac212297b49 100644 > > --- a/drivers/gpu/drm/drm_atomic_helper.c > > +++ b/drivers/gpu/drm/drm_atomic_helper.c > > @@ -230,10 +230,12 @@ update_connector_routing(struct drm_atomic_state *state, int conn_idx) > > } > > > > connector_state->best_encoder = new_encoder; > > - idx = drm_crtc_index(connector_state->crtc); > > + if (connector_state->crtc) { > > + idx = drm_crtc_index(connector_state->crtc); > > > > - crtc_state = state->crtc_states[idx]; > > - crtc_state->mode_changed = true; > > + crtc_state = state->crtc_states[idx]; > > + crtc_state->mode_changed = true; > > + } > > This shouldn't happen since if it does we ended up stealing the encoder > from the connector itself (we do check for connector_state->crtc earlier) > and that would be a bug. I haven't figured out a precise theory but my > guess is on the best_encoder selection, and indeed dp mst encoder > selection seems to have gone belly up in 4.2 with the bisected commit. Well, I just tested Linus's patch and it works. BTW, is there any chance that I can suspend my laptop, and then move it from my docking station at home (where I have a Dell 30" display) to my docking station at work (where I have a Dell 24" display), and actually have the new monitor be detected? For at least the past year, I have to reboot in order to be able to use the external monitor? This used to work, but it's been a very long-standing regression. I undrstand that Multi-stream DP is a evil horrible hack, and supporting it is painful, but this used to work, and it hasn't in a long time. :-( - Ted
On Thu, Jul 30, 2015 at 04:40:02PM +0200, Daniel Vetter wrote: > I have 4 patches in git://people.freedesktop.org/~danvet/drm fixes-stuff > but I couldn't test them yet since no dp mst here and I didn't find > anything that would ship faster than 1-2 weeks yet. I'll try to get some > other people here to test it meanwhile too. I've tried pulling in your patches from fixes-stuff, onto Linus's tree (without Linus's fix), and the good news is that I'm no longer crashing on boot. The *bad* news is that (a) it breaks the external monitor attached to the docking station completely (this was working with Linus's patch), and (b) it's triggering a LOCKDEP failure. So even though Linus's patch wasn't supposed to work, I think I'm going to back to it.... - Ted Jul 30 11:46:49 closure kernel: [ 4.221951] Jul 30 11:46:49 closure kernel: [ 4.221954] ====================================================== Jul 30 11:46:49 closure kernel: [ 4.221957] [ INFO: possible circular locking dependency detected ] Jul 30 11:46:49 closure kernel: [ 4.221960] 4.2.0-rc4-13906-g5f1b75cd #16 Not tainted Jul 30 11:46:49 closure kernel: [ 4.221963] ------------------------------------------------------- Jul 30 11:46:49 closure kernel: [ 4.221966] modprobe/503 is trying to acquire lock: Jul 30 11:46:49 closure kernel: [ 4.221968] (init_mutex){+.+.+.}, at: [<ffffffff8138b380>] acpi_video_get_backlight_type+0x17/0x164 Jul 30 11:46:49 closure kernel: [ 4.221977] Jul 30 11:46:49 closure kernel: [ 4.221977] but task is already holding lock: Jul 30 11:46:49 closure kernel: [ 4.221979] (&(&backlight_notifier)->rwsem){++++..}, at: [<ffffffff8109a7c9>] __blocking_notifier_call_chain+0x37/0x69 Jul 30 11:46:49 closure kernel: [ 4.221987] Jul 30 11:46:49 closure kernel: [ 4.221987] which lock already depends on the new lock. Jul 30 11:46:49 closure kernel: [ 4.221987] Jul 30 11:46:49 closure kernel: [ 4.221990] Jul 30 11:46:49 closure kernel: [ 4.221990] the existing dependency chain (in reverse order) is: Jul 30 11:46:49 closure kernel: [ 4.221995] Jul 30 11:46:49 closure kernel: [ 4.221995] -> #1 (&(&backlight_notifier)->rwsem){++++..}: Jul 30 11:46:49 closure kernel: [ 4.222001] [<ffffffff810bbe08>] lock_acquire+0x104/0x18b Jul 30 11:46:49 closure kernel: [ 4.222007] [<ffffffff8161f1db>] down_write+0x46/0x8a Jul 30 11:46:49 closure kernel: [ 4.222012] [<ffffffff8109a6c0>] blocking_notifier_chain_register+0x36/0x57 Jul 30 11:46:49 closure kernel: [ 4.222017] [<ffffffff8134eb4e>] backlight_register_notifier+0x18/0x1a Jul 30 11:46:49 closure kernel: [ 4.222022] [<ffffffff8138b463>] acpi_video_get_backlight_type+0xfa/0x164 Jul 30 11:46:49 closure kernel: [ 4.222028] [<ffffffffc03a1e45>] 0xffffffffc03a1e45 Jul 30 11:46:49 closure audispd: No plugins found, exiting Jul 30 11:46:49 closure kernel: [ 4.222032] [<ffffffffc03a28a8>] 0xffffffffc03a28a8 Jul 30 11:46:49 closure kernel: [ 4.222036] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af Jul 30 11:46:49 closure kernel: [ 4.222042] [<ffffffff81619985>] do_init_module+0x60/0x1e3 Jul 30 11:46:49 closure kernel: [ 4.222047] [<ffffffff810f0a5b>] load_module+0x1c42/0x2059 Jul 30 11:46:49 closure kernel: [ 4.222052] [<ffffffff810f1046>] SyS_finit_module+0x85/0x92 Jul 30 11:46:49 closure kernel: [ 4.222056] [<ffffffff8162109b>] entry_SYSCALL_64_fastpath+0x16/0x73 Jul 30 11:46:49 closure kernel: [ 4.222060] Jul 30 11:46:49 closure kernel: [ 4.222060] -> #0 (init_mutex){+.+.+.}: Jul 30 11:46:49 closure kernel: [ 4.222065] [<ffffffff810bb77a>] __lock_acquire+0xc55/0xf54 Jul 30 11:46:49 closure kernel: [ 4.222070] [<ffffffff810bbe08>] lock_acquire+0x104/0x18b Jul 30 11:46:49 closure kernel: [ 4.222074] [<ffffffff8161d83a>] mutex_lock_nested+0x70/0x391 Jul 30 11:46:49 closure kernel: [ 4.222078] [<ffffffff8138b380>] acpi_video_get_backlight_type+0x17/0x164 Jul 30 11:46:49 closure kernel: [ 4.222083] [<ffffffff8138b505>] acpi_video_backlight_notify+0x19/0x2f Jul 30 11:46:49 closure kernel: [ 4.222088] [<ffffffff8109a442>] notifier_call_chain+0x4c/0x71 Jul 30 11:46:49 closure kernel: [ 4.222092] [<ffffffff8109a7e2>] __blocking_notifier_call_chain+0x50/0x69 Jul 30 11:46:49 closure kernel: [ 4.222098] [<ffffffff8109a80f>] blocking_notifier_call_chain+0x14/0x16 Jul 30 11:46:49 closure kernel: [ 4.222103] [<ffffffff8134f023>] backlight_device_register+0x1df/0x1f1 Jul 30 11:46:49 closure kernel: [ 4.222108] [<ffffffffc07b3061>] intel_backlight_register+0xf0/0x157 [i915] Jul 30 11:46:49 closure kernel: [ 4.222146] [<ffffffffc078c843>] intel_modeset_gem_init+0x158/0x164 [i915] Jul 30 11:46:49 closure kernel: [ 4.222176] [<ffffffffc07b997c>] i915_driver_load+0xf1c/0x1139 [i915] Jul 30 11:46:49 closure kernel: [ 4.222205] [<ffffffffc053af19>] drm_dev_register+0x84/0xfd [drm] Jul 30 11:46:49 closure kernel: [ 4.222217] [<ffffffffc053d77e>] drm_get_pci_dev+0x102/0x1bc [drm] Jul 30 11:46:49 closure kernel: [ 4.222228] [<ffffffffc07291e2>] i915_pci_probe+0x4f/0x51 [i915] Jul 30 11:46:49 closure kernel: [ 4.222247] [<ffffffff81333ad3>] pci_device_probe+0x74/0xd6 Jul 30 11:46:49 closure kernel: [ 4.222253] [<ffffffff813d4806>] driver_probe_device+0x15f/0x387 Jul 30 11:46:49 closure kernel: [ 4.222257] [<ffffffff813d4a81>] __driver_attach+0x53/0x74 Jul 30 11:46:49 closure kernel: [ 4.222262] [<ffffffff813d2aa0>] bus_for_each_dev+0x6f/0x89 Jul 30 11:46:49 closure kernel: [ 4.222266] [<ffffffff813d41f0>] driver_attach+0x1e/0x20 Jul 30 11:46:49 closure kernel: [ 4.222269] [<ffffffff813d3e33>] bus_add_driver+0x140/0x238 Jul 30 11:46:49 closure kernel: [ 4.222273] [<ffffffff813d53d8>] driver_register+0x8f/0xcc Jul 30 11:46:49 closure kernel: [ 4.222278] [<ffffffff81332be1>] __pci_register_driver+0x5e/0x62 Jul 30 11:46:49 closure kernel: [ 4.222282] [<ffffffffc053d890>] drm_pci_init+0x58/0xda [drm] Jul 30 11:46:49 closure kernel: [ 4.222293] [<ffffffffc081f0a0>] i915_init+0xa0/0xa8 [i915] Jul 30 11:46:49 closure kernel: [ 4.222312] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af Jul 30 11:46:49 closure kernel: [ 4.222317] [<ffffffff81619985>] do_init_module+0x60/0x1e3 Jul 30 11:46:49 closure kernel: [ 4.222321] [<ffffffff810f0a5b>] load_module+0x1c42/0x2059 Jul 30 11:46:49 closure kernel: [ 4.222325] [<ffffffff810f1046>] SyS_finit_module+0x85/0x92 Jul 30 11:46:49 closure kernel: [ 4.222329] [<ffffffff8162109b>] entry_SYSCALL_64_fastpath+0x16/0x73 Jul 30 11:46:49 closure kernel: [ 4.222334] Jul 30 11:46:49 closure kernel: [ 4.222334] other info that might help us debug this: Jul 30 11:46:49 closure kernel: [ 4.222334] Jul 30 11:46:49 closure kernel: [ 4.222340] Possible unsafe locking scenario: Jul 30 11:46:49 closure kernel: [ 4.222340] Jul 30 11:46:49 closure kernel: [ 4.222344] CPU0 CPU1 Jul 30 11:46:49 closure kernel: [ 4.222347] ---- ---- Jul 30 11:46:49 closure kernel: [ 4.222350] lock(&(&backlight_notifier)->rwsem); Jul 30 11:46:49 closure kernel: [ 4.222353] lock(init_mutex); Jul 30 11:46:49 closure kernel: [ 4.222357] lock(&(&backlight_notifier)->rwsem); Jul 30 11:46:49 closure kernel: [ 4.222363] lock(init_mutex); Jul 30 11:46:49 closure kernel: [ 4.222366] Jul 30 11:46:49 closure kernel: [ 4.222366] *** DEADLOCK *** Jul 30 11:46:49 closure kernel: [ 4.222366] Jul 30 11:46:49 closure kernel: [ 4.222371] 4 locks held by modprobe/503: Jul 30 11:46:49 closure kernel: [ 4.222374] #0: (&dev->mutex){......}, at: [<ffffffff813d3ff1>] device_lock+0xf/0x11 Jul 30 11:46:49 closure kernel: [ 4.222381] #1: (&dev->mutex){......}, at: [<ffffffff813d3ff1>] device_lock+0xf/0x11 Jul 30 11:46:49 closure kernel: [ 4.222388] #2: (drm_global_mutex){+.+.+.}, at: [<ffffffffc053aeb9>] drm_dev_register+0x24/0xfd [drm] Jul 30 11:46:49 closure kernel: [ 4.222402] #3: (&(&backlight_notifier)->rwsem){++++..}, at: [<ffffffff8109a7c9>] __blocking_notifier_call_chain+0x37/0x69 Jul 30 11:46:49 closure kernel: [ 4.222410] Jul 30 11:46:49 closure kernel: [ 4.222410] stack backtrace: Jul 30 11:46:49 closure kernel: [ 4.222416] CPU: 7 PID: 503 Comm: modprobe Not tainted 4.2.0-rc4-13906-g5f1b75cd #16 Jul 30 11:46:49 closure kernel: [ 4.222420] Hardware name: LENOVO 20BECTO1WW/20BECTO1WW, BIOS GMET59WW (2.07 ) 02/12/2014 Jul 30 11:46:49 closure kernel: [ 4.222425] ffffffff8280a230 ffff8800c992b5d8 ffffffff8161a71e 0000000000000006 Jul 30 11:46:49 closure kernel: [ 4.222431] ffffffff8280a230 ffff8800c992b628 ffffffff810b9adf ffffffff82265780 Jul 30 11:46:49 closure kernel: [ 4.222437] ffff880405588000 0000000000000004 ffff880405588880 0000000000000004 Jul 30 11:46:49 closure kernel: [ 4.222443] Call Trace: Jul 30 11:46:49 closure kernel: [ 4.222447] [<ffffffff8161a71e>] dump_stack+0x4c/0x65 Jul 30 11:46:49 closure kernel: [ 4.222451] [<ffffffff810b9adf>] print_circular_bug+0x1f8/0x209 Jul 30 11:46:49 closure kernel: [ 4.222455] [<ffffffff810bb77a>] __lock_acquire+0xc55/0xf54 Jul 30 11:46:49 closure kernel: [ 4.222460] [<ffffffff810bbe08>] lock_acquire+0x104/0x18b Jul 30 11:46:49 closure kernel: [ 4.222464] [<ffffffff8138b380>] ? acpi_video_get_backlight_type+0x17/0x164 Jul 30 11:46:49 closure kernel: [ 4.222469] [<ffffffff8161d83a>] mutex_lock_nested+0x70/0x391 Jul 30 11:46:49 closure kernel: [ 4.222472] [<ffffffff8138b380>] ? acpi_video_get_backlight_type+0x17/0x164 Jul 30 11:46:49 closure kernel: [ 4.222476] [<ffffffff8138b380>] ? acpi_video_get_backlight_type+0x17/0x164 Jul 30 11:46:49 closure kernel: [ 4.222480] [<ffffffff8138b380>] acpi_video_get_backlight_type+0x17/0x164 Jul 30 11:46:49 closure kernel: [ 4.222484] [<ffffffff8138b505>] acpi_video_backlight_notify+0x19/0x2f Jul 30 11:46:49 closure kernel: [ 4.222488] [<ffffffff8109a442>] notifier_call_chain+0x4c/0x71 Jul 30 11:46:49 closure kernel: [ 4.222492] [<ffffffff8109a7e2>] __blocking_notifier_call_chain+0x50/0x69 Jul 30 11:46:49 closure kernel: [ 4.222496] [<ffffffff8109a80f>] blocking_notifier_call_chain+0x14/0x16 Jul 30 11:46:49 closure kernel: [ 4.222500] [<ffffffff8134f023>] backlight_device_register+0x1df/0x1f1 Jul 30 11:46:49 closure kernel: [ 4.222530] [<ffffffffc07b3061>] intel_backlight_register+0xf0/0x157 [i915] Jul 30 11:46:49 closure kernel: [ 4.222556] [<ffffffffc078c843>] intel_modeset_gem_init+0x158/0x164 [i915] Jul 30 11:46:49 closure kernel: [ 4.222584] [<ffffffffc07b997c>] i915_driver_load+0xf1c/0x1139 [i915] Jul 30 11:46:49 closure kernel: [ 4.222589] [<ffffffff810ba715>] ? mark_held_locks+0x56/0x6c Jul 30 11:46:49 closure kernel: [ 4.222593] [<ffffffff81620836>] ? _raw_spin_unlock_irqrestore+0x3f/0x4d Jul 30 11:46:49 closure kernel: [ 4.222597] [<ffffffff810ba89c>] ? trace_hardirqs_on_caller+0x171/0x18d Jul 30 11:46:49 closure kernel: [ 4.222607] [<ffffffffc053af19>] drm_dev_register+0x84/0xfd [drm] Jul 30 11:46:49 closure kernel: [ 4.222618] [<ffffffffc053d77e>] drm_get_pci_dev+0x102/0x1bc [drm] Jul 30 11:46:49 closure kernel: [ 4.222636] [<ffffffffc07291e2>] i915_pci_probe+0x4f/0x51 [i915] Jul 30 11:46:49 closure kernel: [ 4.222640] [<ffffffff81333ad3>] pci_device_probe+0x74/0xd6 Jul 30 11:46:49 closure kernel: [ 4.222644] [<ffffffff813d4a2e>] ? driver_probe_device+0x387/0x387 Jul 30 11:46:49 closure kernel: [ 4.222648] [<ffffffff813d4806>] driver_probe_device+0x15f/0x387 Jul 30 11:46:49 closure kernel: [ 4.222652] [<ffffffff813d4a2e>] ? driver_probe_device+0x387/0x387 Jul 30 11:46:49 closure kernel: [ 4.222655] [<ffffffff813d4a81>] __driver_attach+0x53/0x74 Jul 30 11:46:49 closure kernel: [ 4.222659] [<ffffffff813d2aa0>] bus_for_each_dev+0x6f/0x89 Jul 30 11:46:49 closure kernel: [ 4.222662] [<ffffffff813d41f0>] driver_attach+0x1e/0x20 Jul 30 11:46:49 closure kernel: [ 4.222666] [<ffffffff813d3e33>] bus_add_driver+0x140/0x238 Jul 30 11:46:49 closure kernel: [ 4.222670] [<ffffffff813d53d8>] driver_register+0x8f/0xcc Jul 30 11:46:49 closure kernel: [ 4.222674] [<ffffffff81332be1>] __pci_register_driver+0x5e/0x62 Jul 30 11:46:49 closure kernel: [ 4.222677] [<ffffffffc081f000>] ? 0xffffffffc081f000 Jul 30 11:46:49 closure kernel: [ 4.222687] [<ffffffffc053d890>] drm_pci_init+0x58/0xda [drm] Jul 30 11:46:49 closure kernel: [ 4.222690] [<ffffffffc081f000>] ? 0xffffffffc081f000 Jul 30 11:46:49 closure kernel: [ 4.222708] [<ffffffffc081f0a0>] i915_init+0xa0/0xa8 [i915] Jul 30 11:46:49 closure kernel: [ 4.222712] [<ffffffffc081f000>] ? 0xffffffffc081f000 Jul 30 11:46:49 closure kernel: [ 4.222716] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af Jul 30 11:46:49 closure kernel: [ 4.222719] [<ffffffff8161994d>] ? do_init_module+0x28/0x1e3 Jul 30 11:46:49 closure kernel: [ 4.222723] [<ffffffff81199350>] ? kmem_cache_alloc_trace+0xba/0xcc Jul 30 11:46:49 closure kernel: [ 4.222727] [<ffffffff81619985>] do_init_module+0x60/0x1e3 Jul 30 11:46:49 closure kernel: [ 4.222731] [<ffffffff810f0a5b>] load_module+0x1c42/0x2059 Jul 30 11:46:49 closure kernel: [ 4.222736] [<ffffffff810f1046>] SyS_finit_module+0x85/0x92 Jul 30 11:46:49 closure kernel: [ 4.222739] [<ffffffff8162109b>] entry_SYSCALL_64_fastpath+0x16/0x73
On Thu, 30 Jul 2015 17:32:28 +0200, Theodore Ts'o wrote: > > On Thu, Jul 30, 2015 at 04:40:02PM +0200, Daniel Vetter wrote: > > On Wed, Jul 29, 2015 at 10:18:16PM -0700, Linus Torvalds wrote: > > > drivers/gpu/drm/drm_atomic_helper.c | 8 +++++--- > > > 1 file changed, 5 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > > > index 5b59d5ad7d1c..aac212297b49 100644 > > > --- a/drivers/gpu/drm/drm_atomic_helper.c > > > +++ b/drivers/gpu/drm/drm_atomic_helper.c > > > @@ -230,10 +230,12 @@ update_connector_routing(struct drm_atomic_state *state, int conn_idx) > > > } > > > > > > connector_state->best_encoder = new_encoder; > > > - idx = drm_crtc_index(connector_state->crtc); > > > + if (connector_state->crtc) { > > > + idx = drm_crtc_index(connector_state->crtc); > > > > > > - crtc_state = state->crtc_states[idx]; > > > - crtc_state->mode_changed = true; > > > + crtc_state = state->crtc_states[idx]; > > > + crtc_state->mode_changed = true; > > > + } > > > > This shouldn't happen since if it does we ended up stealing the encoder > > from the connector itself (we do check for connector_state->crtc earlier) > > and that would be a bug. I haven't figured out a precise theory but my > > guess is on the best_encoder selection, and indeed dp mst encoder > > selection seems to have gone belly up in 4.2 with the bisected commit. > > Well, I just tested Linus's patch and it works. > > BTW, is there any chance that I can suspend my laptop, and then move > it from my docking station at home (where I have a Dell 30" display) > to my docking station at work (where I have a Dell 24" display), and > actually have the new monitor be detected? For at least the past > year, I have to reboot in order to be able to use the external > monitor? This used to work, but it's been a very long-standing > regression. I undrstand that Multi-stream DP is a evil horrible hack, > and supporting it is painful, but this used to work, and it hasn't in > a long time. :-( Relevant with this? https://bugs.freedesktop.org/show_bug.cgi?id=89589 I wanted to check this by myself, too, as the same bug was reported to openSUSE bugzilla, but I had no hardware showing it. Takashi
On Thu, Jul 30, 2015 at 11:50:29AM -0400, Theodore Ts'o wrote: > I've tried pulling in your patches from fixes-stuff, onto Linus's tree > (without Linus's fix), and the good news is that I'm no longer > crashing on boot. > > The *bad* news is that (a) it breaks the external monitor attached to > the docking station completely (this was working with Linus's patch), > and (b) it's triggering a LOCKDEP failure. Well, that's not fair. Even with Linus's fix, there is still a LOCKDEP failure. And a few more i915 WARNINGS. But at least the external monitor works, so this is what I'm using. Enclosed please find a dmesg with the lockdep and i915 warnings and my .config. The kernel that I used can be found at: https://git.kernel.org/cgit/linux/kernel/git/tytso/ext4.git/log/?h=i915-test-4.2.0-rc4 - Ted
On Thu, Jul 30, 2015 at 11:50:29AM -0400, Theodore Ts'o wrote: > On Thu, Jul 30, 2015 at 04:40:02PM +0200, Daniel Vetter wrote: > > I have 4 patches in git://people.freedesktop.org/~danvet/drm fixes-stuff > > but I couldn't test them yet since no dp mst here and I didn't find > > anything that would ship faster than 1-2 weeks yet. I'll try to get some > > other people here to test it meanwhile too. > > I've tried pulling in your patches from fixes-stuff, onto Linus's tree > (without Linus's fix), and the good news is that I'm no longer > crashing on boot. Ok so I'm not completely clueless yet, the encoder confusion indeed resulted in the follow-up crash. But obviously I don't understand yet exactly what's going on if this breaks the display. > The *bad* news is that (a) it breaks the external monitor attached to > the docking station completely (this was working with Linus's patch), > and (b) it's triggering a LOCKDEP failure. The lockdep splat is all in the driver load before we do any modeset at all, so shouldn't have changed between these patches. Are you sure it's a regression due to mine and wasn't there before? > So even though Linus's patch wasn't supposed to work, I think I'm > going to back to it.... Well I found some dp mst hubs meanwhile so hopefully tomorrow I can test myself what's going wrong here. -Daniel > > - Ted > > > Jul 30 11:46:49 closure kernel: [ 4.221951] > Jul 30 11:46:49 closure kernel: [ 4.221954] ====================================================== > Jul 30 11:46:49 closure kernel: [ 4.221957] [ INFO: possible circular locking dependency detected ] > Jul 30 11:46:49 closure kernel: [ 4.221960] 4.2.0-rc4-13906-g5f1b75cd #16 Not tainted > Jul 30 11:46:49 closure kernel: [ 4.221963] ------------------------------------------------------- > Jul 30 11:46:49 closure kernel: [ 4.221966] modprobe/503 is trying to acquire lock: > Jul 30 11:46:49 closure kernel: [ 4.221968] (init_mutex){+.+.+.}, at: [<ffffffff8138b380>] acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.221977] > Jul 30 11:46:49 closure kernel: [ 4.221977] but task is already holding lock: > Jul 30 11:46:49 closure kernel: [ 4.221979] (&(&backlight_notifier)->rwsem){++++..}, at: [<ffffffff8109a7c9>] __blocking_notifier_call_chain+0x37/0x69 > Jul 30 11:46:49 closure kernel: [ 4.221987] > Jul 30 11:46:49 closure kernel: [ 4.221987] which lock already depends on the new lock. > Jul 30 11:46:49 closure kernel: [ 4.221987] > Jul 30 11:46:49 closure kernel: [ 4.221990] > Jul 30 11:46:49 closure kernel: [ 4.221990] the existing dependency chain (in reverse order) is: > Jul 30 11:46:49 closure kernel: [ 4.221995] > Jul 30 11:46:49 closure kernel: [ 4.221995] -> #1 (&(&backlight_notifier)->rwsem){++++..}: > Jul 30 11:46:49 closure kernel: [ 4.222001] [<ffffffff810bbe08>] lock_acquire+0x104/0x18b > Jul 30 11:46:49 closure kernel: [ 4.222007] [<ffffffff8161f1db>] down_write+0x46/0x8a > Jul 30 11:46:49 closure kernel: [ 4.222012] [<ffffffff8109a6c0>] blocking_notifier_chain_register+0x36/0x57 > Jul 30 11:46:49 closure kernel: [ 4.222017] [<ffffffff8134eb4e>] backlight_register_notifier+0x18/0x1a > Jul 30 11:46:49 closure kernel: [ 4.222022] [<ffffffff8138b463>] acpi_video_get_backlight_type+0xfa/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222028] [<ffffffffc03a1e45>] 0xffffffffc03a1e45 > Jul 30 11:46:49 closure audispd: No plugins found, exiting > Jul 30 11:46:49 closure kernel: [ 4.222032] [<ffffffffc03a28a8>] 0xffffffffc03a28a8 > Jul 30 11:46:49 closure kernel: [ 4.222036] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af > Jul 30 11:46:49 closure kernel: [ 4.222042] [<ffffffff81619985>] do_init_module+0x60/0x1e3 > Jul 30 11:46:49 closure kernel: [ 4.222047] [<ffffffff810f0a5b>] load_module+0x1c42/0x2059 > Jul 30 11:46:49 closure kernel: [ 4.222052] [<ffffffff810f1046>] SyS_finit_module+0x85/0x92 > Jul 30 11:46:49 closure kernel: [ 4.222056] [<ffffffff8162109b>] entry_SYSCALL_64_fastpath+0x16/0x73 > Jul 30 11:46:49 closure kernel: [ 4.222060] > Jul 30 11:46:49 closure kernel: [ 4.222060] -> #0 (init_mutex){+.+.+.}: > Jul 30 11:46:49 closure kernel: [ 4.222065] [<ffffffff810bb77a>] __lock_acquire+0xc55/0xf54 > Jul 30 11:46:49 closure kernel: [ 4.222070] [<ffffffff810bbe08>] lock_acquire+0x104/0x18b > Jul 30 11:46:49 closure kernel: [ 4.222074] [<ffffffff8161d83a>] mutex_lock_nested+0x70/0x391 > Jul 30 11:46:49 closure kernel: [ 4.222078] [<ffffffff8138b380>] acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222083] [<ffffffff8138b505>] acpi_video_backlight_notify+0x19/0x2f > Jul 30 11:46:49 closure kernel: [ 4.222088] [<ffffffff8109a442>] notifier_call_chain+0x4c/0x71 > Jul 30 11:46:49 closure kernel: [ 4.222092] [<ffffffff8109a7e2>] __blocking_notifier_call_chain+0x50/0x69 > Jul 30 11:46:49 closure kernel: [ 4.222098] [<ffffffff8109a80f>] blocking_notifier_call_chain+0x14/0x16 > Jul 30 11:46:49 closure kernel: [ 4.222103] [<ffffffff8134f023>] backlight_device_register+0x1df/0x1f1 > Jul 30 11:46:49 closure kernel: [ 4.222108] [<ffffffffc07b3061>] intel_backlight_register+0xf0/0x157 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222146] [<ffffffffc078c843>] intel_modeset_gem_init+0x158/0x164 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222176] [<ffffffffc07b997c>] i915_driver_load+0xf1c/0x1139 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222205] [<ffffffffc053af19>] drm_dev_register+0x84/0xfd [drm] > Jul 30 11:46:49 closure kernel: [ 4.222217] [<ffffffffc053d77e>] drm_get_pci_dev+0x102/0x1bc [drm] > Jul 30 11:46:49 closure kernel: [ 4.222228] [<ffffffffc07291e2>] i915_pci_probe+0x4f/0x51 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222247] [<ffffffff81333ad3>] pci_device_probe+0x74/0xd6 > Jul 30 11:46:49 closure kernel: [ 4.222253] [<ffffffff813d4806>] driver_probe_device+0x15f/0x387 > Jul 30 11:46:49 closure kernel: [ 4.222257] [<ffffffff813d4a81>] __driver_attach+0x53/0x74 > Jul 30 11:46:49 closure kernel: [ 4.222262] [<ffffffff813d2aa0>] bus_for_each_dev+0x6f/0x89 > Jul 30 11:46:49 closure kernel: [ 4.222266] [<ffffffff813d41f0>] driver_attach+0x1e/0x20 > Jul 30 11:46:49 closure kernel: [ 4.222269] [<ffffffff813d3e33>] bus_add_driver+0x140/0x238 > Jul 30 11:46:49 closure kernel: [ 4.222273] [<ffffffff813d53d8>] driver_register+0x8f/0xcc > Jul 30 11:46:49 closure kernel: [ 4.222278] [<ffffffff81332be1>] __pci_register_driver+0x5e/0x62 > Jul 30 11:46:49 closure kernel: [ 4.222282] [<ffffffffc053d890>] drm_pci_init+0x58/0xda [drm] > Jul 30 11:46:49 closure kernel: [ 4.222293] [<ffffffffc081f0a0>] i915_init+0xa0/0xa8 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222312] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af > Jul 30 11:46:49 closure kernel: [ 4.222317] [<ffffffff81619985>] do_init_module+0x60/0x1e3 > Jul 30 11:46:49 closure kernel: [ 4.222321] [<ffffffff810f0a5b>] load_module+0x1c42/0x2059 > Jul 30 11:46:49 closure kernel: [ 4.222325] [<ffffffff810f1046>] SyS_finit_module+0x85/0x92 > Jul 30 11:46:49 closure kernel: [ 4.222329] [<ffffffff8162109b>] entry_SYSCALL_64_fastpath+0x16/0x73 > Jul 30 11:46:49 closure kernel: [ 4.222334] > Jul 30 11:46:49 closure kernel: [ 4.222334] other info that might help us debug this: > Jul 30 11:46:49 closure kernel: [ 4.222334] > Jul 30 11:46:49 closure kernel: [ 4.222340] Possible unsafe locking scenario: > Jul 30 11:46:49 closure kernel: [ 4.222340] > Jul 30 11:46:49 closure kernel: [ 4.222344] CPU0 CPU1 > Jul 30 11:46:49 closure kernel: [ 4.222347] ---- ---- > Jul 30 11:46:49 closure kernel: [ 4.222350] lock(&(&backlight_notifier)->rwsem); > Jul 30 11:46:49 closure kernel: [ 4.222353] lock(init_mutex); > Jul 30 11:46:49 closure kernel: [ 4.222357] lock(&(&backlight_notifier)->rwsem); > Jul 30 11:46:49 closure kernel: [ 4.222363] lock(init_mutex); > Jul 30 11:46:49 closure kernel: [ 4.222366] > Jul 30 11:46:49 closure kernel: [ 4.222366] *** DEADLOCK *** > Jul 30 11:46:49 closure kernel: [ 4.222366] > Jul 30 11:46:49 closure kernel: [ 4.222371] 4 locks held by modprobe/503: > Jul 30 11:46:49 closure kernel: [ 4.222374] #0: (&dev->mutex){......}, at: [<ffffffff813d3ff1>] device_lock+0xf/0x11 > Jul 30 11:46:49 closure kernel: [ 4.222381] #1: (&dev->mutex){......}, at: [<ffffffff813d3ff1>] device_lock+0xf/0x11 > Jul 30 11:46:49 closure kernel: [ 4.222388] #2: (drm_global_mutex){+.+.+.}, at: [<ffffffffc053aeb9>] drm_dev_register+0x24/0xfd [drm] > Jul 30 11:46:49 closure kernel: [ 4.222402] #3: (&(&backlight_notifier)->rwsem){++++..}, at: [<ffffffff8109a7c9>] __blocking_notifier_call_chain+0x37/0x69 > Jul 30 11:46:49 closure kernel: [ 4.222410] > Jul 30 11:46:49 closure kernel: [ 4.222410] stack backtrace: > Jul 30 11:46:49 closure kernel: [ 4.222416] CPU: 7 PID: 503 Comm: modprobe Not tainted 4.2.0-rc4-13906-g5f1b75cd #16 > Jul 30 11:46:49 closure kernel: [ 4.222420] Hardware name: LENOVO 20BECTO1WW/20BECTO1WW, BIOS GMET59WW (2.07 ) 02/12/2014 > Jul 30 11:46:49 closure kernel: [ 4.222425] ffffffff8280a230 ffff8800c992b5d8 ffffffff8161a71e 0000000000000006 > Jul 30 11:46:49 closure kernel: [ 4.222431] ffffffff8280a230 ffff8800c992b628 ffffffff810b9adf ffffffff82265780 > Jul 30 11:46:49 closure kernel: [ 4.222437] ffff880405588000 0000000000000004 ffff880405588880 0000000000000004 > Jul 30 11:46:49 closure kernel: [ 4.222443] Call Trace: > Jul 30 11:46:49 closure kernel: [ 4.222447] [<ffffffff8161a71e>] dump_stack+0x4c/0x65 > Jul 30 11:46:49 closure kernel: [ 4.222451] [<ffffffff810b9adf>] print_circular_bug+0x1f8/0x209 > Jul 30 11:46:49 closure kernel: [ 4.222455] [<ffffffff810bb77a>] __lock_acquire+0xc55/0xf54 > Jul 30 11:46:49 closure kernel: [ 4.222460] [<ffffffff810bbe08>] lock_acquire+0x104/0x18b > Jul 30 11:46:49 closure kernel: [ 4.222464] [<ffffffff8138b380>] ? acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222469] [<ffffffff8161d83a>] mutex_lock_nested+0x70/0x391 > Jul 30 11:46:49 closure kernel: [ 4.222472] [<ffffffff8138b380>] ? acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222476] [<ffffffff8138b380>] ? acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222480] [<ffffffff8138b380>] acpi_video_get_backlight_type+0x17/0x164 > Jul 30 11:46:49 closure kernel: [ 4.222484] [<ffffffff8138b505>] acpi_video_backlight_notify+0x19/0x2f > Jul 30 11:46:49 closure kernel: [ 4.222488] [<ffffffff8109a442>] notifier_call_chain+0x4c/0x71 > Jul 30 11:46:49 closure kernel: [ 4.222492] [<ffffffff8109a7e2>] __blocking_notifier_call_chain+0x50/0x69 > Jul 30 11:46:49 closure kernel: [ 4.222496] [<ffffffff8109a80f>] blocking_notifier_call_chain+0x14/0x16 > Jul 30 11:46:49 closure kernel: [ 4.222500] [<ffffffff8134f023>] backlight_device_register+0x1df/0x1f1 > Jul 30 11:46:49 closure kernel: [ 4.222530] [<ffffffffc07b3061>] intel_backlight_register+0xf0/0x157 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222556] [<ffffffffc078c843>] intel_modeset_gem_init+0x158/0x164 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222584] [<ffffffffc07b997c>] i915_driver_load+0xf1c/0x1139 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222589] [<ffffffff810ba715>] ? mark_held_locks+0x56/0x6c > Jul 30 11:46:49 closure kernel: [ 4.222593] [<ffffffff81620836>] ? _raw_spin_unlock_irqrestore+0x3f/0x4d > Jul 30 11:46:49 closure kernel: [ 4.222597] [<ffffffff810ba89c>] ? trace_hardirqs_on_caller+0x171/0x18d > Jul 30 11:46:49 closure kernel: [ 4.222607] [<ffffffffc053af19>] drm_dev_register+0x84/0xfd [drm] > Jul 30 11:46:49 closure kernel: [ 4.222618] [<ffffffffc053d77e>] drm_get_pci_dev+0x102/0x1bc [drm] > Jul 30 11:46:49 closure kernel: [ 4.222636] [<ffffffffc07291e2>] i915_pci_probe+0x4f/0x51 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222640] [<ffffffff81333ad3>] pci_device_probe+0x74/0xd6 > Jul 30 11:46:49 closure kernel: [ 4.222644] [<ffffffff813d4a2e>] ? driver_probe_device+0x387/0x387 > Jul 30 11:46:49 closure kernel: [ 4.222648] [<ffffffff813d4806>] driver_probe_device+0x15f/0x387 > Jul 30 11:46:49 closure kernel: [ 4.222652] [<ffffffff813d4a2e>] ? driver_probe_device+0x387/0x387 > Jul 30 11:46:49 closure kernel: [ 4.222655] [<ffffffff813d4a81>] __driver_attach+0x53/0x74 > Jul 30 11:46:49 closure kernel: [ 4.222659] [<ffffffff813d2aa0>] bus_for_each_dev+0x6f/0x89 > Jul 30 11:46:49 closure kernel: [ 4.222662] [<ffffffff813d41f0>] driver_attach+0x1e/0x20 > Jul 30 11:46:49 closure kernel: [ 4.222666] [<ffffffff813d3e33>] bus_add_driver+0x140/0x238 > Jul 30 11:46:49 closure kernel: [ 4.222670] [<ffffffff813d53d8>] driver_register+0x8f/0xcc > Jul 30 11:46:49 closure kernel: [ 4.222674] [<ffffffff81332be1>] __pci_register_driver+0x5e/0x62 > Jul 30 11:46:49 closure kernel: [ 4.222677] [<ffffffffc081f000>] ? 0xffffffffc081f000 > Jul 30 11:46:49 closure kernel: [ 4.222687] [<ffffffffc053d890>] drm_pci_init+0x58/0xda [drm] > Jul 30 11:46:49 closure kernel: [ 4.222690] [<ffffffffc081f000>] ? 0xffffffffc081f000 > Jul 30 11:46:49 closure kernel: [ 4.222708] [<ffffffffc081f0a0>] i915_init+0xa0/0xa8 [i915] > Jul 30 11:46:49 closure kernel: [ 4.222712] [<ffffffffc081f000>] ? 0xffffffffc081f000 > Jul 30 11:46:49 closure kernel: [ 4.222716] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af > Jul 30 11:46:49 closure kernel: [ 4.222719] [<ffffffff8161994d>] ? do_init_module+0x28/0x1e3 > Jul 30 11:46:49 closure kernel: [ 4.222723] [<ffffffff81199350>] ? kmem_cache_alloc_trace+0xba/0xcc > Jul 30 11:46:49 closure kernel: [ 4.222727] [<ffffffff81619985>] do_init_module+0x60/0x1e3 > Jul 30 11:46:49 closure kernel: [ 4.222731] [<ffffffff810f0a5b>] load_module+0x1c42/0x2059 > Jul 30 11:46:49 closure kernel: [ 4.222736] [<ffffffff810f1046>] SyS_finit_module+0x85/0x92 > Jul 30 11:46:49 closure kernel: [ 4.222739] [<ffffffff8162109b>] entry_SYSCALL_64_fastpath+0x16/0x73 > > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel
On Thu, Jul 30, 2015 at 8:57 AM, Takashi Iwai <tiwai@suse.de> wrote: > On Thu, 30 Jul 2015 17:32:28 +0200, > Theodore Ts'o wrote: >> >> BTW, is there any chance that I can suspend my laptop, and then move >> it from my docking station at home (where I have a Dell 30" display) >> to my docking station at work (where I have a Dell 24" display), and >> actually have the new monitor be detected? For at least the past >> year, I have to reboot in order to be able to use the external >> monitor? This used to work, but it's been a very long-standing >> regression. I undrstand that Multi-stream DP is a evil horrible hack, >> and supporting it is painful, but this used to work, and it hasn't in >> a long time. :-( > > Relevant with this? > https://bugs.freedesktop.org/show_bug.cgi?id=89589 > > I wanted to check this by myself, too, as the same bug was reported to > openSUSE bugzilla, but I had no hardware showing it. Hmm. That commit e7d6f7d70829 looks like it should still revert fairly cleanly (just move the call to intel_dp_mst_resume() to before the intel_modeset_setup_hw_state() call and locking). Ted, worth checking out, even if that presumably ends up re-introducing some WARN_ON's.. Linus
On Thu, Jul 30, 2015 at 11:50:29AM -0400, Theodore Ts'o wrote: > On Thu, Jul 30, 2015 at 04:40:02PM +0200, Daniel Vetter wrote: > > I have 4 patches in git://people.freedesktop.org/~danvet/drm fixes-stuff > > but I couldn't test them yet since no dp mst here and I didn't find > > anything that would ship faster than 1-2 weeks yet. I'll try to get some > > other people here to test it meanwhile too. > > I've tried pulling in your patches from fixes-stuff, onto Linus's tree > (without Linus's fix), and the good news is that I'm no longer > crashing on boot. > > The *bad* news is that (a) it breaks the external monitor attached to > the docking station completely (this was working with Linus's patch), > and (b) it's triggering a LOCKDEP failure. > > So even though Linus's patch wasn't supposed to work, I think I'm > going to back to it.... Ok I updated fixes-stuff with just 2 patches which seem to be enough to fix it. Plus a patch to convert Linus' hack into something we can keep plus a drive-by WARNING fix in mst that got in the way for me. Seems to work here in getting rid of the Oops. If this tests out for you too I'll send a pull to Linus. Thanks, Daniel
On Mon, Aug 03, 2015 at 05:27:29PM +0200, Daniel Vetter wrote: > > Ok I updated fixes-stuff with just 2 patches which seem to be enough to > fix it. Plus a patch to convert Linus' hack into something we can keep > plus a drive-by WARNING fix in mst that got in the way for me. > > Seems to work here in getting rid of the Oops. If this tests out for you > too I'll send a pull to Linus. I've just tried pulling in your updated fixes-stuff, and it avoids the oops and allows external the monitor to work correctly. However, I'm still seeing a large number of drm/i915 related warning messages and other kernel kvetching. Thanks!! - Ted [ 4.084198] [drm] Initialized drm 1.1.0 20060810 [ 4.129576] [drm] Memory usable by graphics device = 2048M [ 4.129616] [drm] Replacing VGA console driver [ 4.130315] Console: switching to colour dummy device 80x25 [ 4.145332] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013). [ 4.145334] [drm] Driver supports precise vblank timestamp query. [ 4.146184] vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem [ 4.163778] usbcore: registered new interface driver btusb [ 4.170719] ------------[ cut here ]------------ [ 4.170749] WARNING: CPU: 0 PID: 463 at /usr/projects/linux/linux/drivers/gpu/drm/i915/intel_pm.c:2339 ilk_update_wm+0x71a/0xb27 [i915]() [ 4.170751] WARN_ON(!r->enable) [ 4.170752] Modules linked in: [ 4.170754] btusb btrtl btbcm btintel iwlmvm(+) bluetooth mac80211 iwlwifi snd_hda_intel i915(+) drm_kms_helper snd_hda_codec cfg80211 drm snd_hwdep lpc_ich snd_hda_core intel_gtt thinkpad_acpi tpm_tis nvram tpm intel_smartconnect uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core sch_fq_codel kvm_intel kvm ecryptfs parport_pc ppdev lp parport autofs4 btrfs xor hid_generic usbhid hid raid6_pq microcode rtsx_pci_sdmmc ehci_pci e1000e rtsx_pci ehci_hcd xhci_pci ptp mfd_core pps_core xhci_hcd [ 4.170805] CPU: 0 PID: 463 Comm: systemd-udevd Not tainted 4.2.0-rc5-14194-g130583b #18 [ 4.170807] Hardware name: LENOVO 20BECTO1WW/20BECTO1WW, BIOS GMET59WW (2.07 ) 02/12/2014 [ 4.170809] 0000000000000009 ffff880403f0f4c8 ffffffff8161aaee 0000000000000006 [ 4.170814] ffff880403f0f518 ffff880403f0f508 ffffffff8107e5f0 0000000000000006 [ 4.170818] ffffffffc05ade43 ffff8800c8b70000 ffff8800c7f16000 ffff880405fb48b8 [ 4.170823] Call Trace: [ 4.170829] [<ffffffff8161aaee>] dump_stack+0x4c/0x65 [ 4.170833] [<ffffffff8107e5f0>] warn_slowpath_common+0xa1/0xbb [ 4.170856] [<ffffffffc05ade43>] ? ilk_update_wm+0x71a/0xb27 [i915] [ 4.170859] [<ffffffff8107e650>] warn_slowpath_fmt+0x46/0x48 [ 4.170879] [<ffffffffc05abb1e>] ? ilk_compute_wm_maximums+0x43/0xa2 [i915] [ 4.170899] [<ffffffffc05ade43>] ilk_update_wm+0x71a/0xb27 [i915] [ 4.170921] [<ffffffffc05afb2b>] intel_update_watermarks+0x1e/0x20 [i915] [ 4.170957] [<ffffffffc05ff8d4>] haswell_crtc_disable+0x270/0x2ae [i915] [ 4.170989] [<ffffffffc060199d>] intel_crtc_control+0xa0/0xe1 [i915] [ 4.171020] [<ffffffffc0601a2b>] intel_crtc_update_dpms+0x4d/0x5d [i915] [ 4.171052] [<ffffffffc0607dd9>] intel_modeset_setup_hw_state+0x7b0/0xa90 [i915] [ 4.171081] [<ffffffffc05ec6de>] ? hsw_write64+0xcd/0xcd [i915] [ 4.171113] [<ffffffffc060ab44>] ? ilk_fbc_disable+0x29/0x69 [i915] [ 4.171142] [<ffffffffc0609512>] intel_modeset_init+0x130d/0x14e3 [i915] [ 4.171179] [<ffffffffc0636962>] i915_driver_load+0xf05/0x1139 [i915] [ 4.171183] [<ffffffff810ba787>] ? mark_held_locks+0x56/0x6c [ 4.171186] [<ffffffff81620c06>] ? _raw_spin_unlock_irqrestore+0x3f/0x4d [ 4.171189] [<ffffffff810ba90e>] ? trace_hardirqs_on_caller+0x171/0x18d [ 4.171204] [<ffffffffc042cf19>] drm_dev_register+0x84/0xfd [drm] [ 4.171215] [<ffffffffc042f77e>] drm_get_pci_dev+0x102/0x1bc [drm] [ 4.171237] [<ffffffffc05a61e2>] i915_pci_probe+0x4f/0x51 [i915] [ 4.171240] [<ffffffff81333c33>] pci_device_probe+0x74/0xd6 [ 4.171245] [<ffffffff813d4b8e>] ? driver_probe_device+0x387/0x387 [ 4.171248] [<ffffffff813d4966>] driver_probe_device+0x15f/0x387 [ 4.171250] [<ffffffff813d4b8e>] ? driver_probe_device+0x387/0x387 [ 4.171252] [<ffffffff813d4be1>] __driver_attach+0x53/0x74 [ 4.171255] [<ffffffff813d2c00>] bus_for_each_dev+0x6f/0x89 [ 4.171257] [<ffffffff813d4350>] driver_attach+0x1e/0x20 [ 4.171260] [<ffffffff813d3f93>] bus_add_driver+0x140/0x238 [ 4.171263] [<ffffffff813d5538>] driver_register+0x8f/0xcc [ 4.171266] [<ffffffff81332d41>] __pci_register_driver+0x5e/0x62 [ 4.171268] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.171278] [<ffffffffc042f890>] drm_pci_init+0x58/0xda [drm] [ 4.171281] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.171301] [<ffffffffc069c0a0>] i915_init+0xa0/0xa8 [i915] [ 4.171303] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.171307] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af [ 4.171310] [<ffffffff81619d1d>] ? do_init_module+0x28/0x1e3 [ 4.171313] [<ffffffff81199429>] ? kmem_cache_alloc_trace+0xba/0xcc [ 4.171315] [<ffffffff81619d55>] do_init_module+0x60/0x1e3 [ 4.171319] [<ffffffff810f0acd>] load_module+0x1c42/0x2059 [ 4.171324] [<ffffffff810f10b8>] SyS_finit_module+0x85/0x92 [ 4.171327] [<ffffffff8162145b>] entry_SYSCALL_64_fastpath+0x16/0x73 [ 4.171329] ---[ end trace 7eb514b89de5fc4a ]--- [ 4.171331] ------------[ cut here ]------------ [ 4.171354] WARNING: CPU: 0 PID: 463 at /usr/projects/linux/linux/drivers/gpu/drm/i915/intel_pm.c:2339 ilk_update_wm+0x71a/0xb27 [i915]() [ 4.171355] WARN_ON(!r->enable) [ 4.171357] Modules linked in: [ 4.171358] btusb btrtl btbcm btintel iwlmvm(+) bluetooth mac80211 iwlwifi snd_hda_intel i915(+) drm_kms_helper snd_hda_codec cfg80211 drm snd_hwdep lpc_ich snd_hda_core intel_gtt thinkpad_acpi tpm_tis nvram tpm intel_smartconnect uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core sch_fq_codel kvm_intel kvm ecryptfs parport_pc ppdev lp parport autofs4 btrfs xor hid_generic usbhid hid raid6_pq microcode rtsx_pci_sdmmc ehci_pci e1000e rtsx_pci ehci_hcd xhci_pci ptp mfd_core pps_core xhci_hcd [ 4.171404] CPU: 0 PID: 463 Comm: systemd-udevd Tainted: G W 4.2.0-rc5-14194-g130583b #18 [ 4.171406] Hardware name: LENOVO 20BECTO1WW/20BECTO1WW, BIOS GMET59WW (2.07 ) 02/12/2014 [ 4.171408] 0000000000000009 ffff880403f0f4c8 ffffffff8161aaee 0000000000000006 [ 4.171412] ffff880403f0f518 ffff880403f0f508 ffffffff8107e5f0 0000000000000006 [ 4.171417] ffffffffc05ade43 ffff8800c8b70000 ffff8800c7f15000 ffff880405fb48b8 [ 4.171421] Call Trace: [ 4.171424] [<ffffffff8161aaee>] dump_stack+0x4c/0x65 [ 4.171427] [<ffffffff8107e5f0>] warn_slowpath_common+0xa1/0xbb [ 4.171449] [<ffffffffc05ade43>] ? ilk_update_wm+0x71a/0xb27 [i915] [ 4.171452] [<ffffffff8107e650>] warn_slowpath_fmt+0x46/0x48 [ 4.171472] [<ffffffffc05abb1e>] ? ilk_compute_wm_maximums+0x43/0xa2 [i915] [ 4.171491] [<ffffffffc05ade43>] ilk_update_wm+0x71a/0xb27 [i915] [ 4.171513] [<ffffffffc05afb2b>] intel_update_watermarks+0x1e/0x20 [i915] [ 4.171546] [<ffffffffc05ff8d4>] haswell_crtc_disable+0x270/0x2ae [i915] [ 4.171579] [<ffffffffc060199d>] intel_crtc_control+0xa0/0xe1 [i915] [ 4.171610] [<ffffffffc0601a2b>] intel_crtc_update_dpms+0x4d/0x5d [i915] [ 4.171641] [<ffffffffc0607dd9>] intel_modeset_setup_hw_state+0x7b0/0xa90 [i915] [ 4.171671] [<ffffffffc05ec6de>] ? hsw_write64+0xcd/0xcd [i915] [ 4.171702] [<ffffffffc060ab44>] ? ilk_fbc_disable+0x29/0x69 [i915] [ 4.171733] [<ffffffffc0609512>] intel_modeset_init+0x130d/0x14e3 [i915] [ 4.171770] [<ffffffffc0636962>] i915_driver_load+0xf05/0x1139 [i915] [ 4.171773] [<ffffffff810ba787>] ? mark_held_locks+0x56/0x6c [ 4.171776] [<ffffffff81620c06>] ? _raw_spin_unlock_irqrestore+0x3f/0x4d [ 4.171779] [<ffffffff810ba90e>] ? trace_hardirqs_on_caller+0x171/0x18d [ 4.171791] [<ffffffffc042cf19>] drm_dev_register+0x84/0xfd [drm] [ 4.171802] [<ffffffffc042f77e>] drm_get_pci_dev+0x102/0x1bc [drm] [ 4.171825] [<ffffffffc05a61e2>] i915_pci_probe+0x4f/0x51 [i915] [ 4.171828] [<ffffffff81333c33>] pci_device_probe+0x74/0xd6 [ 4.171831] [<ffffffff813d4b8e>] ? driver_probe_device+0x387/0x387 [ 4.171833] [<ffffffff813d4966>] driver_probe_device+0x15f/0x387 [ 4.171836] [<ffffffff813d4b8e>] ? driver_probe_device+0x387/0x387 [ 4.171838] [<ffffffff813d4be1>] __driver_attach+0x53/0x74 [ 4.171841] [<ffffffff813d2c00>] bus_for_each_dev+0x6f/0x89 [ 4.171844] [<ffffffff813d4350>] driver_attach+0x1e/0x20 [ 4.171846] [<ffffffff813d3f93>] bus_add_driver+0x140/0x238 [ 4.171849] [<ffffffff813d5538>] driver_register+0x8f/0xcc [ 4.171852] [<ffffffff81332d41>] __pci_register_driver+0x5e/0x62 [ 4.171854] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.171866] [<ffffffffc042f890>] drm_pci_init+0x58/0xda [drm] [ 4.171868] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.171890] [<ffffffffc069c0a0>] i915_init+0xa0/0xa8 [i915] [ 4.171893] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.171896] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af [ 4.171898] [<ffffffff81619d1d>] ? do_init_module+0x28/0x1e3 [ 4.171901] [<ffffffff81199429>] ? kmem_cache_alloc_trace+0xba/0xcc [ 4.171904] [<ffffffff81619d55>] do_init_module+0x60/0x1e3 [ 4.171907] [<ffffffff810f0acd>] load_module+0x1c42/0x2059 [ 4.171911] [<ffffffff810f10b8>] SyS_finit_module+0x85/0x92 [ 4.171914] [<ffffffff8162145b>] entry_SYSCALL_64_fastpath+0x16/0x73 [ 4.171916] ---[ end trace 7eb514b89de5fc4b ]--- [ 4.176978] Bluetooth: hci0: read Intel version: 370710018002030d48 [ 4.176981] Bluetooth: hci0: Intel device is already patched. patch num: 48 [ 4.181839] ====================================================== [ 4.181844] [ INFO: possible circular locking dependency detected ] [ 4.181849] 4.2.0-rc5-14194-g130583b #18 Tainted: G W [ 4.181854] ------------------------------------------------------- [ 4.181859] systemd-udevd/463 is trying to acquire lock: [ 4.181864] (init_mutex){+.+.+.}, at: [<ffffffff8138b4e0>] acpi_video_get_backlight_type+0x17/0x164 [ 4.181878] but task is already holding lock: [ 4.181883] (&(&backlight_notifier)->rwsem){++++..}, at: [<ffffffff8109a7cc>] __blocking_notifier_call_chain+0x37/0x69 [ 4.181895] which lock already depends on the new lock. [ 4.181902] the existing dependency chain (in reverse order) is: [ 4.181912] -> #1 (&(&backlight_notifier)->rwsem){++++..}: [ 4.181923] [<ffffffff810bbe7a>] lock_acquire+0x104/0x18b [ 4.181932] [<ffffffff8161f5ab>] down_write+0x46/0x8a [ 4.181942] [<ffffffff8109a6c3>] blocking_notifier_chain_register+0x36/0x57 [ 4.181953] [<ffffffff8134ecae>] backlight_register_notifier+0x18/0x1a [ 4.181962] [<ffffffff8138b5c3>] acpi_video_get_backlight_type+0xfa/0x164 [ 4.181973] [<ffffffffc03d2e45>] 0xffffffffc03d2e45 [ 4.181981] [<ffffffffc03d38a8>] 0xffffffffc03d38a8 [ 4.181988] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af [ 4.181997] [<ffffffff81619d55>] do_init_module+0x60/0x1e3 [ 4.182006] [<ffffffff810f0acd>] load_module+0x1c42/0x2059 [ 4.182015] [<ffffffff810f10b8>] SyS_finit_module+0x85/0x92 [ 4.182023] [<ffffffff8162145b>] entry_SYSCALL_64_fastpath+0x16/0x73 [ 4.182031] -> #0 (init_mutex){+.+.+.}: [ 4.182042] [<ffffffff810bb7ec>] __lock_acquire+0xc55/0xf54 [ 4.182050] [<ffffffff810bbe7a>] lock_acquire+0x104/0x18b [ 4.182058] [<ffffffff8161dc0a>] mutex_lock_nested+0x70/0x391 [ 4.182066] [<ffffffff8138b4e0>] acpi_video_get_backlight_type+0x17/0x164 [ 4.182077] [<ffffffff8138b665>] acpi_video_backlight_notify+0x19/0x2f [ 4.182086] [<ffffffff8109a445>] notifier_call_chain+0x4c/0x71 [ 4.182094] [<ffffffff8109a7e5>] __blocking_notifier_call_chain+0x50/0x69 [ 4.182105] [<ffffffff8109a812>] blocking_notifier_call_chain+0x14/0x16 [ 4.182116] [<ffffffff8134f183>] backlight_device_register+0x1df/0x1f1 [ 4.182125] [<ffffffffc063005e>] intel_backlight_register+0xf0/0x157 [i915] [ 4.182174] [<ffffffffc0609840>] intel_modeset_gem_init+0x158/0x164 [i915] [ 4.182214] [<ffffffffc0636979>] i915_driver_load+0xf1c/0x1139 [i915] [ 4.182253] [<ffffffffc042cf19>] drm_dev_register+0x84/0xfd [drm] [ 4.182271] [<ffffffffc042f77e>] drm_get_pci_dev+0x102/0x1bc [drm] [ 4.182287] [<ffffffffc05a61e2>] i915_pci_probe+0x4f/0x51 [i915] [ 4.182314] [<ffffffff81333c33>] pci_device_probe+0x74/0xd6 [ 4.182322] [<ffffffff813d4966>] driver_probe_device+0x15f/0x387 [ 4.182331] [<ffffffff813d4be1>] __driver_attach+0x53/0x74 [ 4.182339] [<ffffffff813d2c00>] bus_for_each_dev+0x6f/0x89 [ 4.182347] [<ffffffff813d4350>] driver_attach+0x1e/0x20 [ 4.182355] [<ffffffff813d3f93>] bus_add_driver+0x140/0x238 [ 4.182363] [<ffffffff813d5538>] driver_register+0x8f/0xcc [ 4.182371] [<ffffffff81332d41>] __pci_register_driver+0x5e/0x62 [ 4.182379] [<ffffffffc042f890>] drm_pci_init+0x58/0xda [drm] [ 4.182396] [<ffffffffc069c0a0>] i915_init+0xa0/0xa8 [i915] [ 4.182423] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af [ 4.182432] [<ffffffff81619d55>] do_init_module+0x60/0x1e3 [ 4.182440] [<ffffffff810f0acd>] load_module+0x1c42/0x2059 [ 4.182448] [<ffffffff810f10b8>] SyS_finit_module+0x85/0x92 [ 4.182456] [<ffffffff8162145b>] entry_SYSCALL_64_fastpath+0x16/0x73 [ 4.182465] other info that might help us debug this: [ 4.182477] Possible unsafe locking scenario: [ 4.182486] CPU0 CPU1 [ 4.182491] ---- ---- [ 4.182497] lock(&(&backlight_notifier)->rwsem); [ 4.182504] lock(init_mutex); [ 4.182512] lock(&(&backlight_notifier)->rwsem); [ 4.182522] lock(init_mutex); [ 4.182528] *** DEADLOCK *** [ 4.182540] 4 locks held by systemd-udevd/463: [ 4.182546] #0: (&dev->mutex){......}, at: [<ffffffff813d4151>] device_lock+0xf/0x11 [ 4.182560] #1: (&dev->mutex){......}, at: [<ffffffff813d4151>] device_lock+0xf/0x11 [ 4.182574] #2: (drm_global_mutex){+.+.+.}, at: [<ffffffffc042ceb9>] drm_dev_register+0x24/0xfd [drm] [ 4.182596] #3: (&(&backlight_notifier)->rwsem){++++..}, at: [<ffffffff8109a7cc>] __blocking_notifier_call_chain+0x37/0x69 [ 4.182612] stack backtrace: [ 4.182622] CPU: 0 PID: 463 Comm: systemd-udevd Tainted: G W 4.2.0-rc5-14194-g130583b #18 [ 4.182632] Hardware name: LENOVO 20BECTO1WW/20BECTO1WW, BIOS GMET59WW (2.07 ) 02/12/2014 [ 4.182642] ffffffff8280b780 ffff880403f0f5d8 ffffffff8161aaee 0000000000000006 [ 4.182654] ffffffff8280b780 ffff880403f0f628 ffffffff810b9b51 ffffffff82265780 [ 4.182667] ffff880403de0000 0000000000000004 ffff880403de0880 0000000000000004 [ 4.182679] Call Trace: [ 4.182685] [<ffffffff8161aaee>] dump_stack+0x4c/0x65 [ 4.182693] [<ffffffff810b9b51>] print_circular_bug+0x1f8/0x209 [ 4.182701] [<ffffffff810bb7ec>] __lock_acquire+0xc55/0xf54 [ 4.182710] [<ffffffff810bbe7a>] lock_acquire+0x104/0x18b [ 4.182717] [<ffffffff8138b4e0>] ? acpi_video_get_backlight_type+0x17/0x164 [ 4.182726] [<ffffffff8161dc0a>] mutex_lock_nested+0x70/0x391 [ 4.182734] [<ffffffff8138b4e0>] ? acpi_video_get_backlight_type+0x17/0x164 [ 4.182742] [<ffffffff8138b4e0>] ? acpi_video_get_backlight_type+0x17/0x164 [ 4.182750] [<ffffffff8138b4e0>] acpi_video_get_backlight_type+0x17/0x164 [ 4.182759] [<ffffffff8138b665>] acpi_video_backlight_notify+0x19/0x2f [ 4.182766] [<ffffffff8109a445>] notifier_call_chain+0x4c/0x71 [ 4.182774] [<ffffffff8109a7e5>] __blocking_notifier_call_chain+0x50/0x69 [ 4.182782] [<ffffffff8109a812>] blocking_notifier_call_chain+0x14/0x16 [ 4.182790] [<ffffffff8134f183>] backlight_device_register+0x1df/0x1f1 [ 4.182833] [<ffffffffc063005e>] intel_backlight_register+0xf0/0x157 [i915] [ 4.182872] [<ffffffffc0609840>] intel_modeset_gem_init+0x158/0x164 [i915] [ 4.182915] [<ffffffffc0636979>] i915_driver_load+0xf1c/0x1139 [i915] [ 4.182924] [<ffffffff810ba787>] ? mark_held_locks+0x56/0x6c [ 4.182932] [<ffffffff81620c06>] ? _raw_spin_unlock_irqrestore+0x3f/0x4d [ 4.182940] [<ffffffff810ba90e>] ? trace_hardirqs_on_caller+0x171/0x18d [ 4.182956] [<ffffffffc042cf19>] drm_dev_register+0x84/0xfd [drm] [ 4.182972] [<ffffffffc042f77e>] drm_get_pci_dev+0x102/0x1bc [drm] [ 4.182998] [<ffffffffc05a61e2>] i915_pci_probe+0x4f/0x51 [i915] [ 4.183006] [<ffffffff81333c33>] pci_device_probe+0x74/0xd6 [ 4.183014] [<ffffffff813d4b8e>] ? driver_probe_device+0x387/0x387 [ 4.183021] [<ffffffff813d4966>] driver_probe_device+0x15f/0x387 [ 4.183029] [<ffffffff813d4b8e>] ? driver_probe_device+0x387/0x387 [ 4.183036] [<ffffffff813d4be1>] __driver_attach+0x53/0x74 [ 4.183043] [<ffffffff813d2c00>] bus_for_each_dev+0x6f/0x89 [ 4.183050] [<ffffffff813d4350>] driver_attach+0x1e/0x20 [ 4.183058] [<ffffffff813d3f93>] bus_add_driver+0x140/0x238 [ 4.183065] [<ffffffff813d5538>] driver_register+0x8f/0xcc [ 4.183073] [<ffffffff81332d41>] __pci_register_driver+0x5e/0x62 [ 4.183080] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.183095] [<ffffffffc042f890>] drm_pci_init+0x58/0xda [drm] [ 4.183102] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.183126] [<ffffffffc069c0a0>] i915_init+0xa0/0xa8 [i915] [ 4.183132] [<ffffffffc069c000>] ? 0xffffffffc069c000 [ 4.183139] [<ffffffff810003c7>] do_one_initcall+0x19a/0x1af [ 4.183146] [<ffffffff81619d1d>] ? do_init_module+0x28/0x1e3 [ 4.183153] [<ffffffff81199429>] ? kmem_cache_alloc_trace+0xba/0xcc [ 4.183161] [<ffffffff81619d55>] do_init_module+0x60/0x1e3 [ 4.183169] [<ffffffff810f0acd>] load_module+0x1c42/0x2059 [ 4.183178] [<ffffffff810f10b8>] SyS_finit_module+0x85/0x92 [ 4.183185] [<ffffffff8162145b>] entry_SYSCALL_64_fastpath+0x16/0x73 [ 4.186598] ACPI: Video Device [VID] (multi-head: yes rom: no post: no) [ 4.191522] snd_hda_intel 0000:00:03.0: bound 0000:00:02.0 (ops i915_audio_component_bind_ops [i915]) [ 4.191536] [drm] Initialized i915 1.6.0 20150522 for 0000:00:02.0 on minor 0 [ 4.191691] i801_smbus 0000:00:1f.3: SMBus using PCI interrupt [ 4.248792] [drm] GMBUS [i915 gmbus dpb] timed out, falling back to bit banging on pin 5 [ 4.322899] fbcon: inteldrmfb (fb0) is primary device [ 5.440946] Console: switching to colour frame buffer device 360x101 [ 5.452747] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device [ 5.452767] i915 0000:00:02.0: registered panic notifier
On Mon, Aug 3, 2015 at 9:25 AM, Theodore Ts'o <tytso@mit.edu> wrote: > > I've just tried pulling in your updated fixes-stuff, and it avoids the > oops and allows external the monitor to work correctly. Good. Have either of you tested the suspend/resume behavior? Is that fixed too? > However, I'm > still seeing a large number of drm/i915 related warning messages and > other kernel kvetching. I suspect I can live with that for now. The lockdep one looks like it's mainly an initialization issue, so you'd never get the actual deadlock in practice, but it's obviously annoying. The intel_pm.c one I'll have to defer to the i915 people for.. I'll be travelling much of this week (flying to Finland tomorrow, back on Sunday - yay, 30h in airplanes for three days on the ground, but it's my dad's bday), and my internet will be sporadic. But I'll have a laptop and be able to pull stuff every once in a while. It would be good to have this one resolved, and I just need to worry about the remaining VM problem.. Linus > [ 4.170749] WARNING: CPU: 0 PID: 463 at drivers/gpu/drm/i915/intel_pm.c:2339 ilk_update_wm+0x71a/0xb27 [i915]() > [ 4.170751] WARN_ON(!r->enable)
On Mon, Aug 03, 2015 at 10:24:53AM -0700, Linus Torvalds wrote: > On Mon, Aug 3, 2015 at 9:25 AM, Theodore Ts'o <tytso@mit.edu> wrote: > > > > I've just tried pulling in your updated fixes-stuff, and it avoids the > > oops and allows external the monitor to work correctly. > > Good. Have either of you tested the suspend/resume behavior? Is that fixed too? No, I haven't had a chance to test the suspend/resume behavior, because that requires suspending at work, going home, and connecting to a dock which has a different monitor attached to it, and resuming (or vice versa of suspending at home and then resuming at work). So it's a bit trickier for me to test. It's also not a regression, and the workaround of rebooting is annoying, but I've lived with it for several releases now, but I'll try the two patches/changes that folks had suggested hopefully later this week. - Ted
On Mon, Aug 3, 2015 at 7:24 PM, Linus Torvalds <torvalds@linux-foundation.org> wrote: >> However, I'm >> still seeing a large number of drm/i915 related warning messages and >> other kernel kvetching. > > I suspect I can live with that for now. The lockdep one looks like > it's mainly an initialization issue, so you'd never get the actual > deadlock in practice, but it's obviously annoying. The intel_pm.c one > I'll have to defer to the i915 people for.. The lockdep splat is just acpi being inconsistent with init_mutex vs. backlight notifier_chain (which has it's own lock) calls. init_mutex is new in 4.2 and has been added in commit 87521e16a7abbf3fa337f56cb4d1e18247f15e8a Author: Hans de Goede <hdegoede@redhat.com> Date: Tue Jun 16 16:27:48 2015 +0200 acpi-video-detect: Rewrite backlight interface selection logic Not mine ;-) But adding relevant people. I'll send you a pull for the mst one tomorrow and look into the watermark fail in intel_pm.c too. -Daniel
On Tuesday, August 04, 2015 12:05:14 AM Daniel Vetter wrote: > On Mon, Aug 3, 2015 at 7:24 PM, Linus Torvalds > <torvalds@linux-foundation.org> wrote: > >> However, I'm > >> still seeing a large number of drm/i915 related warning messages and > >> other kernel kvetching. > > > > I suspect I can live with that for now. The lockdep one looks like > > it's mainly an initialization issue, so you'd never get the actual > > deadlock in practice, but it's obviously annoying. The intel_pm.c one > > I'll have to defer to the i915 people for.. > > The lockdep splat is just acpi being inconsistent with init_mutex vs. > backlight notifier_chain (which has it's own lock) calls. init_mutex > is new in 4.2 and has been added in > > commit 87521e16a7abbf3fa337f56cb4d1e18247f15e8a > Author: Hans de Goede <hdegoede@redhat.com> > Date: Tue Jun 16 16:27:48 2015 +0200 > > acpi-video-detect: Rewrite backlight interface selection logic > > > Not mine ;-) But adding relevant people. Hans, can you have a look at this, please? Rafael
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 5b59d5ad7d1c..aac212297b49 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -230,10 +230,12 @@ update_connector_routing(struct drm_atomic_state *state, int conn_idx) } connector_state->best_encoder = new_encoder; - idx = drm_crtc_index(connector_state->crtc); + if (connector_state->crtc) { + idx = drm_crtc_index(connector_state->crtc); - crtc_state = state->crtc_states[idx]; - crtc_state->mode_changed = true; + crtc_state = state->crtc_states[idx]; + crtc_state->mode_changed = true; + } DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] using [ENCODER:%d:%s] on [CRTC:%d]\n", connector->base.id,