Just in case the caller passes in 0 for both slow&fast timeouts, make
sure we initialise the stack value returned. Add an assert so that we
don't make the mistake of passing 0 timeouts for the wait.
drivers/gpu/drm/i915/intel_uncore.c:2011 __intel_wait_for_register_fw() error: uninitialized symbol 'reg_value'.
References: 3f649ab728 ("treewide: Remove uninitialized_var() usage")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200916105022.28316-1-chris@chris-wilson.co.uk
To implement preempt-to-busy (and so efficient timeslicing and best utilization
of the hardware submission ports) we let the GPU run asynchronously in respect
to the ELSP submission queue. This created challenges in keeping and accessing
the driver state mirroring the asynchronous GPU execution.
The latest occurence of this was spotted by KCSAN:
[ 1413.563200] BUG: KCSAN: data-race in __await_execution+0x217/0x370 [i915]
[ 1413.563221]
[ 1413.563236] race at unknown origin, with read to 0xffff88885bb6c478 of 8 bytes by task 9654 on cpu 1:
[ 1413.563548] __await_execution+0x217/0x370 [i915]
[ 1413.563891] i915_request_await_dma_fence+0x4eb/0x6a0 [i915]
[ 1413.564235] i915_request_await_object+0x421/0x490 [i915]
[ 1413.564577] i915_gem_do_execbuffer+0x29b7/0x3c40 [i915]
[ 1413.564967] i915_gem_execbuffer2_ioctl+0x22f/0x5c0 [i915]
[ 1413.564998] drm_ioctl_kernel+0x156/0x1b0
[ 1413.565022] drm_ioctl+0x2ff/0x480
[ 1413.565046] __x64_sys_ioctl+0x87/0xd0
[ 1413.565069] do_syscall_64+0x4d/0x80
[ 1413.565094] entry_SYSCALL_64_after_hwframe+0x44/0xa9
To complicate matters, we have to both avoid the read tearing of *active and
avoid any write tearing as perform the pending[] -> inflight[] promotion of the
execlists.
This is because we cannot rely on the memcpy doing u64 aligned copies on all
kernels/platforms and so we opt to open-code it with explicit WRITE_ONCE
annotations to satisfy KCSAN.
v2: When in doubt, write the same comment again.
v3: Expanded commit message.
Fixes: b55230e5e8 ("drm/i915: Check for awaits on still currently executing requests")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200716142207.13003-1-chris@chris-wilson.co.uk
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
[Joonas: Rebased and reordered into drm-intel-gt-next branch]
[Joonas: Added expanded commit message from Tvrtko and Chris]
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
(cherry picked from commit b4d9145b01)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
As we now protect the timeline list using RCU, we can drop the
timeline->mutex for guarding the list iteration during context close, as
we are searching for an inflight request. Any new request will see the
context is banned and not be submitted. In doing so, pull the checks for
a concurrent submission of the request (notably the
i915_request_completed()) under the engine spinlock, to fully serialise
with __i915_request_submit()). That is in the case of preempt-to-busy
where the request may be completed during the __i915_request_submit(),
we need to be careful that we sample the request status after
serialising so that we don't miss the request the engine is actually
submitting.
Fixes: 4a31741521 ("drm/i915/gem: Refine occupancy test in kill_context()")
References: d22d2d073e ("drm/i915: Protect i915_request_await_start from early waits") # rcu protection of timeline->requests
References: https://gitlab.freedesktop.org/drm/intel/-/issues/1622
References: https://gitlab.freedesktop.org/drm/intel/-/issues/2158
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200806105954.7766-1-chris@chris-wilson.co.uk
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
(cherry picked from commit 736e785f9b)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
The constant N value (0x8000) is used by i915 DP
driver. Define this value in dp helper header file
to use in multiple Display Port drivers. Change
i915 driver accordingly.
Change in v6: Change commit message
Signed-off-by: Chandan Uddaraju <chandanu@codeaurora.org>
Signed-off-by: Vara Reddy <varar@codeaurora.org>
Signed-off-by: Tanmay Shah <tanmay@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rob Clark <robdclark@chromium.org>
On Tigerlake, we are seeing a repeat of commit d8f5053117 ("drm/i915/icl:
Forcibly evict stale csb entries") where, presumably, due to a missing
Global Observation Point synchronisation, the write pointer of the CSB
ringbuffer is updated _prior_ to the contents of the ringbuffer. That is
we see the GPU report more context-switch entries for us to parse, but
those entries have not been written, leading us to process stale events,
and eventually report a hung GPU.
However, this effect appears to be much more severe than we previously
saw on Icelake (though it might be best if we try the same approach
there as well and measure), and Bruce suggested the good idea of resetting
the CSB entry after use so that we can detect when it has been updated by
the GPU. By instrumenting how long that may be, we can set a reliable
upper bound for how long we should wait for:
513 late, avg of 61 retries (590 ns), max of 1061 retries (10099 ns)
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2045
References: d8f5053117 ("drm/i915/icl: Forcibly evict stale csb entries")
References: HSDES#22011327657, HSDES#1508287568
Suggested-by: Bruce Chang <yu.bruce.chang@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Bruce Chang <yu.bruce.chang@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: stable@vger.kernel.org # v5.4
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200915134923.30088-2-chris@chris-wilson.co.uk
Since the display hardware is all there even when INTEL_DISPLAY_ENABLED
return false we have to be capable of shutting it down cleanly so
as to not anger the hw. To that end let's reduce the effect of
!INTEL_DISPLAY_ENABLE to just treating all outputs as disconnected.
Should prevent anyone from automagically enabling any of them, while
still allowing us to cleanly shut them down.
v2: Put the check into the right place for CRT
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200910164256.25983-1-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Having a mode where the display hardware is present but we try
to pretend it isn't just leads to massive headaches when trying
to reason what the fallout might be from skipping some random
bits of programming.
Let's just neuter INTEL_DISPLAY_ENABLED so that we treat the
hardware as fully present, except we just don't register any
outputs. That's still rather sketchy if the outputs are already
enabled when the driver is loaded. I think the simplest solution
would be to probe everything as normal and just return
disconnected" from all .detect() hooks. That would avoid anything
automagically enabling those outputs, but the driver could then
shut things down using the normal codepaths.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200909213824.12390-1-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
If we create a new node, it is possible for the slab allocator to return
us a recently freed node. If that node was just retired, it will retain
the current jiffy as its node->age. There is then a miniscule window,
where as that node is retired, it will appear on the free list with an
incorrect age and be eligible for reuse by one thread, and then by a
second thread as the correct node->age is written.
Fixes: 06b73c2d0b ("drm/i915/gt: Delay taking the spinlock for grabbing from the buffer pool")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200915091417.4086-3-chris@chris-wilson.co.uk
On 32b, highmem using a finite set of indirect PTE (i.e. vmap) to provide
virtual mappings of the high pages. As these are finite, map_new_virtual()
must wait for some other kmap() to finish when it runs out. If we map a
large number of objects, there is no method for it to tell us to release
the mappings, and we deadlock.
However, if we make an explicit vmap of the page, that uses a larger
vmalloc arena, and also has the ability to tell us to release unwanted
mappings. Most importantly, it will fail and propagate an error instead
of waiting forever.
Fixes: fb8621d3be ("drm/i915: Avoid allocating a vmap arena for a single page") #x86-32
References: e87666b52f ("drm/i915/shrinker: Hook up vmap allocation failure notifier")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Cc: <stable@vger.kernel.org> # v4.7+
Link: https://patchwork.freedesktop.org/patch/msgid/20200915091417.4086-1-chris@chris-wilson.co.uk
We update the timestamping constants per-crtc explicitly in
intel_crtc_update_active_timings(). Furtermore the helper will
use uapi.adjusted_mode whereas we want hw.adjusted_mode. Thus
let's drop the helper call an rely on what we already have in
intel_crtc_update_active_timings(). We can now also drop the
hw.adjusted_mode -> uapi.adjusted_mode copy hack that was added
to keep the helper from deriving the timestamping constants from
the wrong thing.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200907120026.6360-3-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The timestamping constants have nothing to do with any legacy state
so should not be updated from
drm_atomic_helper_update_legacy_modeset_state().
Let's make everyone call drm_atomic_helper_calc_timestamping_constants()
directly instead of relying on
drm_atomic_helper_update_legacy_modeset_state() to call it.
@@
expression S;
@@
- drm_atomic_helper_calc_timestamping_constants(S);
@@
expression D, S;
@@
drm_atomic_helper_update_legacy_modeset_state(D, S);
+ drm_atomic_helper_calc_timestamping_constants(S);
v2: Update drm_crtc_vblank_helper_get_vblank_timestamp{,_internal}() docs (Daniel)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200907120026.6360-2-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Paul needs 1a21e5b930 ("drm/ingenic: Fix leak of device_node
pointer") and 3b5b005ef7 ("drm/ingenic: Fix driver not probing when
IPU port is missing") from -fixes to be able to merge further ingenic
patches into -next.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Even if we're not doing downscaling we should account for
some of the extra dotclock limitations for g4x+ sprites. In
particular we must never exceed the 90% rule, and with RGB
that limits actually drops to 80%.
So instead of bailing out when upscaling let's clamp the
scaling factor appropriately and go through the rest of
calculation normally. By luck we already did the full
calculations for the 1:1 case.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200206201204.31704-1-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Current BDW virtual display port is initialized as PORT_B, so need
to use same port for VFIO EDID region, otherwise invalid EDID blob
pointer is assigned which caused kernel null pointer reference. We
might evaluate actual display hotplug for BDW to make this function
work as expected, anyway this is always required to be fixed first.
Reported-by: Alejandro Sior <aho@sior.be>
Cc: Alejandro Sior <aho@sior.be>
Fixes: 0178f4ce3c ("drm/i915/gvt: Enable vfio edid for all GVT supported platform")
Reviewed-by: Hang Yuan <hang.yuan@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200914030302.2775505-1-zhenyuw@linux.intel.com