linux.git/drivers/gpu, branch v5.6-rc3 Linux kernel source tree Merge tag 'drm-intel-fixes-2020-02-20' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes 2020-02-21T02:46:54+00:00 Dave Airlie airlied@redhat.com 2020-02-21T02:46:54+00:00 97d9a4e9619a822c5baf6a63e6f5b80fee4d4213 drm/i915 fixes for v5.6-rc3: - Workaround missing Display Stream Compression (DSC) state readout by forcing modeset when its enabled at probe - Fix EHL port clock voltage level requirements - Fix queuing retire workers on the virtual engine - Fix use of partially initialized waiters - Stop using drm_pci_alloc/drm_pci/free - Fix rewind of RING_TAIL by forcing a context reload - Fix locking on resetting ring->head - Propagate our bug filing URL change to stable kernels Signed-off-by: Dave Airlie <airlied@redhat.com> From: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/87y2sxtsrd.fsf@intel.com 
drm/i915 fixes for v5.6-rc3:
- Workaround missing Display Stream Compression (DSC) state readout by
  forcing modeset when its enabled at probe
- Fix EHL port clock voltage level requirements
- Fix queuing retire workers on the virtual engine
- Fix use of partially initialized waiters
- Stop using drm_pci_alloc/drm_pci/free
- Fix rewind of RING_TAIL by forcing a context reload
- Fix locking on resetting ring->head
- Propagate our bug filing URL change to stable kernels

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87y2sxtsrd.fsf@intel.com
Merge tag 'drm-misc-fixes-2020-02-20' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes 2020-02-21T02:31:16+00:00 Dave Airlie airlied@redhat.com 2020-02-21T02:30:23+00:00 c1368b347fe81d9271412797fea8788dd5dc16b3 drm-misc-fixes for v5.6-rc3: - Fix dt binding for sunxi. - Allow only 1 rotation argument, and allow 0 rotation in video cmdline. - Small compiler warning fix for panfrost. - Fix when using performance counters in panfrost when using per fd address space. Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/f5a6370d-9898-6c72-43e4-5bb56a99b6f2@linux.intel.com 
drm-misc-fixes for v5.6-rc3:
- Fix dt binding for sunxi.
- Allow only 1 rotation argument, and allow 0 rotation in video cmdline.
- Small compiler warning fix for panfrost.
- Fix when using performance counters in panfrost when using per fd address space.

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/f5a6370d-9898-6c72-43e4-5bb56a99b6f2@linux.intel.com
Merge branch 'linux-5.6' of git://github.com/skeggsb/linux into drm-fixes 2020-02-20T02:00:44+00:00 Dave Airlie airlied@redhat.com 2020-02-20T02:00:06+00:00 7c42545cad101fbb9811b55a3b9b697efba6555a Nothing major here, another TU1xx modesetting fix, and hooking up ACR/GR support on TU11x now that NVIDIA have made the firmware available. Signed-off-by: Dave Airlie <airlied@redhat.com> From: Ben Skeggs <skeggsb@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/ <CACAvsv64yBq4KHJ8D-5HQ5eeotApJSMiD+V2ut4f3BonUggf0Q@mail.gmail.com 
Nothing major here, another TU1xx modesetting fix, and hooking up
ACR/GR support on TU11x now that NVIDIA have made the firmware
available.

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Ben Skeggs <skeggsb@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ <CACAvsv64yBq4KHJ8D-5HQ5eeotApJSMiD+V2ut4f3BonUggf0Q@mail.gmail.com
Merge tag 'drm-msm-fixes-2020-02-16' of https://gitlab.freedesktop.org/drm/msm into drm-fixes 2020-02-20T01:01:33+00:00 Dave Airlie airlied@redhat.com 2020-02-20T01:01:28+00:00 ec0bd60a4790066bb4426f87a878816392552257 + fix UBWC on GPU and display side for sc7180 + fix DSI suspend/resume issue encountered on sc7180 + fix some breakage on so called "linux-android" devices (fallout from sc7180/a618 support, not seen earlier due to bootloader/firmware differences) + couple other misc fixes Signed-off-by: Dave Airlie <airlied@redhat.com> From: Rob Clark <robdclark@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/ <CAF6AEGshz5K3tJd=NsBSHq6HGT-ZRa67qt+iN=U2ZFO2oD8kuw@mail.gmail.com 
+ fix UBWC on GPU and display side for sc7180
+ fix DSI suspend/resume issue encountered on sc7180
+ fix some breakage on so called "linux-android" devices
  (fallout from sc7180/a618 support, not seen earlier
  due to bootloader/firmware differences)
+ couple other misc fixes

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rob Clark <robdclark@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ <CAF6AEGshz5K3tJd=NsBSHq6HGT-ZRa67qt+iN=U2ZFO2oD8kuw@mail.gmail.com
drm/amdgpu/display: clean up hdcp workqueue handling 2020-02-19T16:03:24+00:00 Alex Deucher alexander.deucher@amd.com 2020-02-18T18:20:30+00:00 6c62ce8073daf27ae3fd03b6929d6cea3887eeb2 Use the existence of the workqueue itself to determine when to enable HDCP features rather than sprinkling asic checks all over the code. Also add a check for the existence of the hdcp workqueue in the irq handling on the off chance we get and HPD RX interrupt with the CP bit set. This avoids a crash if the driver doesn't support HDCP for a particular asic. Fixes: 96a3b32e67236f ("drm/amd/display: only enable HDCP for DCN+") Bug: https://bugzilla.kernel.org/show_bug.cgi?id=206519 Reviewed-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
Use the existence of the workqueue itself to determine when to
enable HDCP features rather than sprinkling asic checks all over
the code.  Also add a check for the existence of the hdcp
workqueue in the irq handling on the off chance we get and HPD
RX interrupt with the CP bit set.  This avoids a crash if
the driver doesn't support HDCP for a particular asic.

Fixes: 96a3b32e67236f ("drm/amd/display: only enable HDCP for DCN+")
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=206519
Reviewed-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu: add is_raven_kicker judgement for raven1 2020-02-19T15:33:42+00:00 changzhu Changfeng.Zhu@amd.com 2020-02-14T02:57:17+00:00 debcf83770073f90c9b075134650fdc758ff3033 The rlc version of raven_kicer_rlc is different from the legacy rlc version of raven_rlc. So it needs to add a judgement function for raven_kicer_rlc and avoid disable GFXOFF when loading raven_kicer_rlc. Signed-off-by: changzhu <Changfeng.Zhu@amd.com> Reviewed-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
The rlc version of raven_kicer_rlc is different from the legacy rlc
version of raven_rlc. So it needs to add a judgement function for
raven_kicer_rlc and avoid disable GFXOFF when loading raven_kicer_rlc.

Signed-off-by: changzhu <Changfeng.Zhu@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/i915/gt: Avoid resetting ring->head outside of its timeline mutex 2020-02-18T07:53:18+00:00 Chris Wilson chris@chris-wilson.co.uk 2020-02-11T12:01:31+00:00 15de9cb5c9c83a23be92b8f7a1178cead1486587 We manipulate ring->head while active in i915_request_retire underneath the timeline manipulation. We cannot rely on a stable ring->head outside of the timeline->mutex, in particular while setting up the context for resume and reset. Closes: https://gitlab.freedesktop.org/drm/intel/issues/1126 Fixes: 0881954965e3 ("drm/i915: Introduce intel_context.pin_mutex for pin management") Fixes: e5dadff4b093 ("drm/i915: Protect request retirement with timeline->mutex") References: f3c0efc9fe7a ("drm/i915/execlists: Leave resetting ring to intel_ring") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Andi Shyti <andi.shyti@intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200211120131.958949-1-chris@chris-wilson.co.uk (cherry picked from commit 42827350f75c56d0fe9f15d8425a1390528958b6) Signed-off-by: Jani Nikula <jani.nikula@intel.com> 
We manipulate ring->head while active in i915_request_retire underneath
the timeline manipulation. We cannot rely on a stable ring->head outside
of the timeline->mutex, in particular while setting up the context for
resume and reset.

Closes: https://gitlab.freedesktop.org/drm/intel/issues/1126
Fixes: 0881954965e3 ("drm/i915: Introduce intel_context.pin_mutex for pin management")
Fixes: e5dadff4b093 ("drm/i915: Protect request retirement with timeline->mutex")
References: f3c0efc9fe7a ("drm/i915/execlists: Leave resetting ring to intel_ring")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211120131.958949-1-chris@chris-wilson.co.uk
(cherry picked from commit 42827350f75c56d0fe9f15d8425a1390528958b6)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
drm/i915/execlists: Always force a context reload when rewinding RING_TAIL 2020-02-18T07:53:09+00:00 Chris Wilson chris@chris-wilson.co.uk 2020-02-07T21:14:52+00:00 b1339ecac661e1cf3e1dc78ac56bff3aeeaeb92c If we rewind the RING_TAIL on a context, due to a preemption event, we must force the context restore for the RING_TAIL update to be properly handled. Rather than note which preemption events may cause us to rewind the tail, compare the new request's tail with the previously submitted RING_TAIL, as it turns out that timeslicing was causing unexpected rewinds. <idle>-0 0d.s2 1280851190us : __execlists_submission_tasklet: 0000:00:02.0 rcs0: expired last=130:4698, prio=3, hint=3 <idle>-0 0d.s2 1280851192us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 66:119966, current 119964 <idle>-0 0d.s2 1280851195us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 130:4698, current 4695 <idle>-0 0d.s2 1280851198us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 130:4696, current 4695 ^---- Note we unwind 2 requests from the same context <idle>-0 0d.s2 1280851208us : __i915_request_submit: 0000:00:02.0 rcs0: fence 130:4696, current 4695 <idle>-0 0d.s2 1280851213us : __i915_request_submit: 0000:00:02.0 rcs0: fence 134:1508, current 1506 ^---- But to apply the new timeslice, we have to replay the first request before the new client can start -- the unexpected RING_TAIL rewind <idle>-0 0d.s2 1280851219us : trace_ports: 0000:00:02.0 rcs0: submit { 130:4696*, 134:1508 } synmark2-5425 2..s. 1280851239us : process_csb: 0000:00:02.0 rcs0: cs-irq head=5, tail=0 synmark2-5425 2..s. 1280851240us : process_csb: 0000:00:02.0 rcs0: csb[0]: status=0x00008002:0x00000000 ^---- Preemption event for the ELSP update; note the lite-restore synmark2-5425 2..s. 1280851243us : trace_ports: 0000:00:02.0 rcs0: preempted { 130:4698, 66:119966 } synmark2-5425 2..s. 1280851246us : trace_ports: 0000:00:02.0 rcs0: promote { 130:4696*, 134:1508 } synmark2-5425 2.... 1280851462us : __i915_request_commit: 0000:00:02.0 rcs0: fence 130:4700, current 4695 synmark2-5425 2.... 1280852111us : __i915_request_commit: 0000:00:02.0 rcs0: fence 130:4702, current 4695 synmark2-5425 2.Ns1 1280852296us : process_csb: 0000:00:02.0 rcs0: cs-irq head=0, tail=2 synmark2-5425 2.Ns1 1280852297us : process_csb: 0000:00:02.0 rcs0: csb[1]: status=0x00000814:0x00000000 synmark2-5425 2.Ns1 1280852299us : trace_ports: 0000:00:02.0 rcs0: completed { 130:4696!, 134:1508 } synmark2-5425 2.Ns1 1280852301us : process_csb: 0000:00:02.0 rcs0: csb[2]: status=0x00000818:0x00000040 synmark2-5425 2.Ns1 1280852302us : trace_ports: 0000:00:02.0 rcs0: completed { 134:1508, 0:0 } synmark2-5425 2.Ns1 1280852313us : process_csb: process_csb:2336 GEM_BUG_ON(!i915_request_completed(*execlists->active) && !reset_in_progress(execlists)) Fixes: 8ee36e048c98 ("drm/i915/execlists: Minimalistic timeslicing") Referenecs: 82c69bf58650 ("drm/i915/gt: Detect if we miss WaIdleLiteRestore") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: <stable@vger.kernel.org> # v5.4+ Link: https://patchwork.freedesktop.org/patch/msgid/20200207211452.2860634-1-chris@chris-wilson.co.uk (cherry picked from commit 5ba32c7be81e53ea8a27190b0f6be98e6c6779af) Signed-off-by: Jani Nikula <jani.nikula@intel.com> 
If we rewind the RING_TAIL on a context, due to a preemption event, we
must force the context restore for the RING_TAIL update to be properly
handled. Rather than note which preemption events may cause us to rewind
the tail, compare the new request's tail with the previously submitted
RING_TAIL, as it turns out that timeslicing was causing unexpected
rewinds.

   <idle>-0       0d.s2 1280851190us : __execlists_submission_tasklet: 0000:00:02.0 rcs0: expired last=130:4698, prio=3, hint=3
   <idle>-0       0d.s2 1280851192us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 66:119966, current 119964
   <idle>-0       0d.s2 1280851195us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 130:4698, current 4695
   <idle>-0       0d.s2 1280851198us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 130:4696, current 4695
^----  Note we unwind 2 requests from the same context

   <idle>-0       0d.s2 1280851208us : __i915_request_submit: 0000:00:02.0 rcs0: fence 130:4696, current 4695
   <idle>-0       0d.s2 1280851213us : __i915_request_submit: 0000:00:02.0 rcs0: fence 134:1508, current 1506
^---- But to apply the new timeslice, we have to replay the first request
      before the new client can start -- the unexpected RING_TAIL rewind

   <idle>-0       0d.s2 1280851219us : trace_ports: 0000:00:02.0 rcs0: submit { 130:4696*, 134:1508 }
 synmark2-5425    2..s. 1280851239us : process_csb: 0000:00:02.0 rcs0: cs-irq head=5, tail=0
 synmark2-5425    2..s. 1280851240us : process_csb: 0000:00:02.0 rcs0: csb[0]: status=0x00008002:0x00000000
^---- Preemption event for the ELSP update; note the lite-restore

 synmark2-5425    2..s. 1280851243us : trace_ports: 0000:00:02.0 rcs0: preempted { 130:4698, 66:119966 }
 synmark2-5425    2..s. 1280851246us : trace_ports: 0000:00:02.0 rcs0: promote { 130:4696*, 134:1508 }
 synmark2-5425    2.... 1280851462us : __i915_request_commit: 0000:00:02.0 rcs0: fence 130:4700, current 4695
 synmark2-5425    2.... 1280852111us : __i915_request_commit: 0000:00:02.0 rcs0: fence 130:4702, current 4695
 synmark2-5425    2.Ns1 1280852296us : process_csb: 0000:00:02.0 rcs0: cs-irq head=0, tail=2
 synmark2-5425    2.Ns1 1280852297us : process_csb: 0000:00:02.0 rcs0: csb[1]: status=0x00000814:0x00000000
 synmark2-5425    2.Ns1 1280852299us : trace_ports: 0000:00:02.0 rcs0: completed { 130:4696!, 134:1508 }
 synmark2-5425    2.Ns1 1280852301us : process_csb: 0000:00:02.0 rcs0: csb[2]: status=0x00000818:0x00000040
 synmark2-5425    2.Ns1 1280852302us : trace_ports: 0000:00:02.0 rcs0: completed { 134:1508, 0:0 }
 synmark2-5425    2.Ns1 1280852313us : process_csb: process_csb:2336 GEM_BUG_ON(!i915_request_completed(*execlists->active) && !reset_in_progress(execlists))

Fixes: 8ee36e048c98 ("drm/i915/execlists: Minimalistic timeslicing")
Referenecs: 82c69bf58650 ("drm/i915/gt: Detect if we miss WaIdleLiteRestore")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.4+
Link: https://patchwork.freedesktop.org/patch/msgid/20200207211452.2860634-1-chris@chris-wilson.co.uk
(cherry picked from commit 5ba32c7be81e53ea8a27190b0f6be98e6c6779af)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
drm/i915: Wean off drm_pci_alloc/drm_pci_free 2020-02-18T07:52:54+00:00 Chris Wilson chris@chris-wilson.co.uk 2020-02-02T15:39:34+00:00 aa3146193ae25d0fe4b96d815169a135db2e8f01 drm_pci_alloc and drm_pci_free are just very thin wrappers around dma_alloc_coherent, with a note that we should be removing them. Furthermore since commit de09d31dd38a50fdce106c15abd68432eebbd014 Author: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Date: Fri Jan 15 16:51:42 2016 -0800 page-flags: define PG_reserved behavior on compound pages As far as I can see there's no users of PG_reserved on compound pages. Let's use PF_NO_COMPOUND here. drm_pci_alloc has been declared broken since it mixes GFP_COMP and SetPageReserved. Avoid this conflict by weaning ourselves off using the abstraction and using the dma functions directly. Reported-by: Taketo Kabe Closes: https://gitlab.freedesktop.org/drm/intel/issues/1027 Fixes: de09d31dd38a ("page-flags: define PG_reserved behavior on compound pages") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: <stable@vger.kernel.org> # v4.5+ Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20200202153934.3899472-1-chris@chris-wilson.co.uk (cherry picked from commit c6790dc22312f592c1434577258b31c48c72d52a) Signed-off-by: Jani Nikula <jani.nikula@intel.com> 
drm_pci_alloc and drm_pci_free are just very thin wrappers around
dma_alloc_coherent, with a note that we should be removing them.
Furthermore since

commit de09d31dd38a50fdce106c15abd68432eebbd014
Author: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Date:   Fri Jan 15 16:51:42 2016 -0800

    page-flags: define PG_reserved behavior on compound pages

    As far as I can see there's no users of PG_reserved on compound pages.
    Let's use PF_NO_COMPOUND here.

drm_pci_alloc has been declared broken since it mixes GFP_COMP and
SetPageReserved. Avoid this conflict by weaning ourselves off using the
abstraction and using the dma functions directly.

Reported-by: Taketo Kabe
Closes: https://gitlab.freedesktop.org/drm/intel/issues/1027
Fixes: de09d31dd38a ("page-flags: define PG_reserved behavior on compound pages")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: <stable@vger.kernel.org> # v4.5+
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200202153934.3899472-1-chris@chris-wilson.co.uk
(cherry picked from commit c6790dc22312f592c1434577258b31c48c72d52a)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
drm/i915/gt: Protect defer_request() from new waiters 2020-02-17T19:24:19+00:00 Chris Wilson chris@chris-wilson.co.uk 2020-02-06T20:49:13+00:00 19b5f3b419a61808ff2713f1f30b8a88fe14ac9b Mika spotted <4>[17436.705441] general protection fault: 0000 [#1] PREEMPT SMP PTI <4>[17436.705447] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.5.0+ #1 <4>[17436.705449] Hardware name: System manufacturer System Product Name/Z170M-PLUS, BIOS 3805 05/16/2018 <4>[17436.705512] RIP: 0010:__execlists_submission_tasklet+0xc4d/0x16e0 [i915] <4>[17436.705516] Code: c5 4c 8d 60 e0 75 17 e9 8c 07 00 00 49 8b 44 24 20 49 39 c5 4c 8d 60 e0 0f 84 7a 07 00 00 49 8b 5c 24 08 49 8b 87 80 00 00 00 <48> 39 83 d8 fe ff ff 75 d9 48 8b 83 88 fe ff ff a8 01 0f 84 b6 05 <4>[17436.705518] RSP: 0018:ffffc9000012ce80 EFLAGS: 00010083 <4>[17436.705521] RAX: ffff88822ae42000 RBX: 5a5a5a5a5a5a5a5a RCX: dead000000000122 <4>[17436.705523] RDX: ffff88822ae42588 RSI: ffff8881e32a7908 RDI: ffff8881c429fd48 <4>[17436.705525] RBP: ffffc9000012cf00 R08: ffff88822ae42588 R09: 00000000fffffffe <4>[17436.705527] R10: ffff8881c429fb80 R11: 00000000a677cf08 R12: ffff8881c42a0aa8 <4>[17436.705529] R13: ffff8881c429fd38 R14: ffff88822ae42588 R15: ffff8881c429fb80 <4>[17436.705532] FS: 0000000000000000(0000) GS:ffff88822ed00000(0000) knlGS:0000000000000000 <4>[17436.705534] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4>[17436.705536] CR2: 00007f858c76d000 CR3: 0000000005610003 CR4: 00000000003606e0 <4>[17436.705538] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 <4>[17436.705540] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 <4>[17436.705542] Call Trace: <4>[17436.705545] <IRQ> <4>[17436.705603] execlists_submission_tasklet+0xc0/0x130 [i915] which is us consuming a partially initialised new waiter in defer_requests(). We can prevent this by initialising the i915_dependency prior to making it visible, and since we are using a concurrent list_add/iterator mark them up to the compiler. Fixes: 8ee36e048c98 ("drm/i915/execlists: Minimalistic timeslicing") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200206204915.2636606-2-chris@chris-wilson.co.uk (cherry picked from commit f14f27b1663269a81ed62d3961fe70250a1a0623) Signed-off-by: Jani Nikula <jani.nikula@intel.com> 
Mika spotted

<4>[17436.705441] general protection fault: 0000 [#1] PREEMPT SMP PTI
<4>[17436.705447] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.5.0+ #1
<4>[17436.705449] Hardware name: System manufacturer System Product Name/Z170M-PLUS, BIOS 3805 05/16/2018
<4>[17436.705512] RIP: 0010:__execlists_submission_tasklet+0xc4d/0x16e0 [i915]
<4>[17436.705516] Code: c5 4c 8d 60 e0 75 17 e9 8c 07 00 00 49 8b 44 24 20 49 39 c5 4c 8d 60 e0 0f 84 7a 07 00 00 49 8b 5c 24 08 49 8b 87 80 00 00 00 <48> 39 83 d8 fe ff ff 75 d9 48 8b 83 88 fe ff ff a8 01 0f 84 b6 05
<4>[17436.705518] RSP: 0018:ffffc9000012ce80 EFLAGS: 00010083
<4>[17436.705521] RAX: ffff88822ae42000 RBX: 5a5a5a5a5a5a5a5a RCX: dead000000000122
<4>[17436.705523] RDX: ffff88822ae42588 RSI: ffff8881e32a7908 RDI: ffff8881c429fd48
<4>[17436.705525] RBP: ffffc9000012cf00 R08: ffff88822ae42588 R09: 00000000fffffffe
<4>[17436.705527] R10: ffff8881c429fb80 R11: 00000000a677cf08 R12: ffff8881c42a0aa8
<4>[17436.705529] R13: ffff8881c429fd38 R14: ffff88822ae42588 R15: ffff8881c429fb80
<4>[17436.705532] FS:  0000000000000000(0000) GS:ffff88822ed00000(0000) knlGS:0000000000000000
<4>[17436.705534] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4>[17436.705536] CR2: 00007f858c76d000 CR3: 0000000005610003 CR4: 00000000003606e0
<4>[17436.705538] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
<4>[17436.705540] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
<4>[17436.705542] Call Trace:
<4>[17436.705545]  <IRQ>
<4>[17436.705603]  execlists_submission_tasklet+0xc0/0x130 [i915]

which is us consuming a partially initialised new waiter in
defer_requests(). We can prevent this by initialising the i915_dependency
prior to making it visible, and since we are using a concurrent
list_add/iterator mark them up to the compiler.

Fixes: 8ee36e048c98 ("drm/i915/execlists: Minimalistic timeslicing")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200206204915.2636606-2-chris@chris-wilson.co.uk
(cherry picked from commit f14f27b1663269a81ed62d3961fe70250a1a0623)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>