Fix typo: "TRIGER" --> "TRIGGER"

The two misplelled macros:

1) OAREPORTTRIG1_EDGE_LEVEL_TRIGER_SELECT_MASK
2) OAREPORTTRIG5_EDGE_LEVEL_TRIGER_SELECT_MASK

are not used in any other sources of the kernel,
so this change can be consider only a local change
for the i915_reg.h file.
Signed-off-by: NFlavio Suligoi <f.suligoi@asem.it>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200703125046.8395-1-f.suligoi@asem.it

It is not really unexpected to hit wedge on init this way.
We're already downgrading error printk when running with fault injection,
let's use the same approach for CI tainting.

v2: Don't check fault inject in trace dump (Chris)
Signed-off-by: NMichał Winiarski <michal.winiarski@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Petri Latvala <petri.latvala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200706144107.204821-3-michal@hardline.pl

We can add taint from multiple places, printing the caller allows us to
have a better overview of what exactly caused us to do the tainting.

v2: Tweak format and print the device (Chris)
v3: Move things around (Chris)
Suggested-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: NMichał Winiarski <michal.winiarski@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Petri Latvala <petri.latvala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200706144107.204821-2-michal@hardline.pl

Getting wedged device on driver init is pretty much unrecoverable.
Since we're running various scenarios that may potentially hit this in
CI (module reload / selftests / hotunplug), and if it happens, it means
that we can't trust any subsequent CI results, we should just apply the
taint to let the CI know that it should reboot (CI checks taint between
test runs).

v2: Comment that WEDGED_ON_INIT is non-recoverable, distinguish
    WEDGED_ON_INIT from WEDGED_ON_FINI (Chris)
v3: Appease checkpatch, fixup search-replace logic expression mindbomb
    in assert (Chris)
Signed-off-by: NMichał Winiarski <michal.winiarski@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Petri Latvala <petri.latvala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200706144107.204821-1-michal@hardline.pl

The initial CI results did not include a TGL system which includes a
panel that is having issues with patch. Revert while we triage.

This reverts commit 680c45c7.
Signed-off-by: NMatt Atwood <matthew.s.atwood@intel.com>
Reviewed-by: NManasi Navare <manasi.d.navare@intel.com>
Signed-off-by: NJosé Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702230957.30536-1-matthew.s.atwood@intel.com

Reuse the ppgtt_bind_vma() for aliasing_ppgtt_bind_vma() so we can
reduce some code near-duplication. The catch is that we need to then
pass along the i915_address_space and not rely on vma->vm, as they
differ with the aliasing-ppgtt.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200703102519.26539-1-chris@chris-wilson.co.uk

Normally i85x/i865 3D activity will block FBC until a 2D blit
occurs. I suppose this was meant to avoid recompression while
3D activity is still going on but the frame hasn't yet been
presented. Unfortunately that also means that a page flipped
3D workload will permanently block FBC even if it only renders
a single frame and then does nothing.

Since we are using software render tracking anyway we might as
well flip the chicken bit so that 3D does not block FBC. This
will avoid the permament FBC blockage in the aforemention use
case, but thanks to the software tracking the compressor will
not disturb 3D rendering activity.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702153723.24327-5-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

Unlike all the other pre-snb desktop platforms i865 actually
supports FBC. Let's enable it.

Quote from the spec:
"DevSDG provides the same Run-Length Encoded Frame Buffer
 Compression (RLEFBC) function as exists in DevMGM."

As i865 only has the one pipe we want to skip massaging the
plane<->pipe assignment aimed at getting FBC+LVDS working on
the mobile platforms.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702153723.24327-4-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

The MSG_FBC_REND_STATE register only exists on snb+. For older
platforms (would also work for snb+) we can simply rewite DSPSURF
to trigger a flip nuke.

While generally RMW is considered harmful we'll use it here for
simplicity. And since FBC doesn't exist in i830 we don't have to
worry about the DSPSURF double buffering hardware fails present
on that platform.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702153723.24327-3-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

Consult the actual plane stride instead of the fb stride. The two
will disagree when we remap the gtt. The plane stride is what the
hw will be fed so that's what we should look at for the FBC
retrictions/cfb allocation.

Since we no longer require a fence we are going to attempt using
FBC with remapping, and so we should look at correct stride.

With 90/270 degree rotation the plane stride is stored in units
of pixels, so we need to conver it to bytes for the purposes
of calculating the cfb stride. Not entirely sure if this matches
the hw behaviour though. Need to reverse engineer that at some
point...

We also need to reorder the pixel format check vs. stride check
to avoid triggering a spurious WARN(stride & 63) with cpp==1 and
plane stride==32.

v2: Try to deal with rotated stride and related WARN

Cc: José Roberto de Souza <jose.souza@intel.com>
Fixes: 691f7ba5 ("drm/i915/display/fbc: Make fences a nice-to-have for GEN9+")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702153723.24327-2-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

We still need "Bump up CDCLK" workaround otherwise getting
underruns - however currently it blocks 8K as CDCLK = Pixel rate,
in 8K case would require CDCLK to be around 1 Ghz which is not
possible.

v2: - Convert to expression(max(min_cdclk, min(pixel_rate, max_cdclk))
      (Ville Syrjälä)
    - Use type specific min_t, max_t(Ville Syrjälä)

Fixes: 46d53e27 ("Revert "drm/i915: Remove unneeded hack now for CDCLK"")
Signed-off-by: NStanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: NManasi Navare <manasi.d.navare@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702091526.10096-1-stanislav.lisovskiy@intel.com

The information about platform/driver/user view of GuC firmware usage
currently requires user to either go through kernel log or parse the
combination of "enable_guc" modparam and various debugfs entries.
Let's keep things simple and add a "supported/used/wanted" matrix
(already used internally by i915) in guc_info debugfs.
Signed-off-by: NMichał Winiarski <michal.winiarski@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Lukasz Fiedorowicz <lukasz.fiedorowicz@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: NLukasz Fiedorowicz <lukasz.fiedorowicz@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200701142752.419878-1-michal@hardline.pl

Since gen8 we don't use swizzle anymore. Don't dump registers related to
it: registers may or may not be there.

v2: pull the rest of driver state reporting before the read out (Chris)

Cc: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: NLucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702200714.1278-1-lucas.demarchi@intel.com

Rather than reuse the common ctx->mutex for locking the execbuffer LUT,
split it into its own lock to avoid being taken [as part of ctx->mutex]
at inappropriate times. In particular to avoid the inversion from taking
the timeline->mutex for the whole execbuf submission in the next patch.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200703004306.11117-1-chris@chris-wilson.co.uk

Not only do we need to release the vm.ref we acquired for the vma on the
duplicate insert branch, but also for the normal error paths, so roll
them all into one.
Reported-by: NAndi Shyti <andi.shyti@intel.com>
Suggested-by: NAndi Shyti <andi.shyti@intel.com>
Fixes: 2850748e ("drm/i915: Pull i915_vma_pin under the vm->mutex")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702211015.29604-1-chris@chris-wilson.co.uk

Since we no longer always take struct_mutex around everything, and want
the freedom to create GEM objects, actually taking struct_mutex inside
the lock creation ends up pulling the mutex inside other looks. Since we
don't use generally use struct_mutex, we can relax the tainting.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702083225.20044-3-chris@chris-wilson.co.uk

Avoid waking up the device and taking stale locks if we know that the
object is not currently mmapped. This is particularly useful as not many
object are actually mmapped and so we can destroy them without waking
the device up, and gives us a little more freedom of workqueue ordering
during shutdown.

v2: Pull the release_mmap() into its single user in freeing the objects,
where there can not be any race with a concurrent user of the freed
object. Or so one hopes!
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
Link: https://patchwork.freedesktop.org/patch/msgid/20200702163623.6402-2-chris@chris-wilson.co.uk

Only a GGTT mmapping will use the aperture detiling registers, so on a
tiling change for an object, we only need to revoke those mmappings and
not the CPU mmappings (which are always linear irrespective of the tiling).
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702163623.6402-1-chris@chris-wilson.co.uk

We have a mix of dport, intel_dport, intel_dig_port and dig_port to
reference a intel_digital_port struct. Numbers are around

5	intel_dport
36	dport
479	intel_dig_port
352	dig_port

Since we already removed the intel_ prefix from most of our other
structs, do the same here and prefer dig_port.

v2: rename everything in i915, not just a few display sources and
reword commit message (from Matt Roper)
Signed-off-by: NLucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200701045054.23357-1-lucas.demarchi@intel.com

Signed-off-by: NJani Nikula <jani.nikula@intel.com>

As we allow for parallel threads to create the same vma instance
concurrently, and we only filter out the duplicates upon reacquiring the
spinlock for the rbtree, we have to free the loser of the constructors'
race. When freeing, we should also drop any resource references acquired
for the redundant vma.

Fixes: 2850748e ("drm/i915: Pull i915_vma_pin under the vm->mutex")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702083225.20044-1-chris@chris-wilson.co.uk

As we ensure that the heartbeat is reasonably fast (and should not
block), move the heartbeat work into the system_highpri_wq to avoid
having this essential task be blocked behind other slow work, such as
our own retire_work_handler.

References: https://gitlab.freedesktop.org/drm/intel/-/issues/2119Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702095219.963-2-chris@chris-wilson.co.uk

If the driver gets stuck holding the kernel timeline, we cannot issue a
heartbeat and so fail to discover that the driver is indeed stuck and do
not issue a GPU reset (which would hopefully unstick the driver!).
Switch to using a trylock so that we can query if the heartbeat's
timeline mutex is locked elsewhere, and then use the timer to probe if it
remains stuck at the same spot for consecutive heartbeats, indicating
that the mutex has not been released and the engine has not progressed.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702095219.963-1-chris@chris-wilson.co.uk

intel_dp_set_source_rates() calls intel_dp_is_edp(), which is unsafe to
use before encoder_type is set. This caused GEN11+ to incorrectly strip
HBR3 from source rates for edp. Move intel_dp_set_source_rates() to
after encoder_type is set. Add comment to intel_dp_is_edp() describing
unsafe usages.

v2: Alter intel_dp_set_source_rates final position (Ville/Manasi).
    Remove outdated comment (Ville).
    Slight optimization of control flow in intel_dp_init_connector.
    Slight rewording in commit message.
Signed-off-by: NMatt Atwood <matthew.s.atwood@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJosé Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200630233310.10191-1-matthew.s.atwood@intel.com

'level' here means the highest level we can't use, so when checking
the fbc watermarks we need a -1 to get at the last enabled level.

While at if refactor the code a bit to declutter
g4x_compute_pipe_wm().
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-12-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

To simplify things, call the combo PHY/TBT PLL calculation functions
directly from the corresponding combo/TypeC PLL get functions, instead of
calling the same calculation functions after having to recheck if the
given PHY is combo or TypeC.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200629185848.20550-2-imre.deak@intel.com

When the reference clock is 38.4MHz, using the current TBT PLL
fractional divider value results in a slightly off TBT link frequency.
This causes an endless loop of link training success followed by a bad
link signaling and retraining at least on a Dell WD19TB TBT dock.  The
workaround provided by the HW team is to divide the fractional divider
value by two. This fixed the link training problem on the ThinkPad dock.

The same workaround is needed on some EHL platforms and for combo PHY
PLLs, these will be addressed in a follow-up.

Bspec: 49204

References: HSDES#22010772725
References: HSDES#14011861142
Reported-and-tested-by: NKhaled Almahallawy <khaled.almahallawy@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NKhaled Almahallawy <khaled.almahallawy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200629185848.20550-1-imre.deak@intel.com

The obj->lut_list is traversed when the object is closed as the file
table is destroyed during process termination. As this occurs before we
kill any outstanding context if, due to some bug or another, the closure
is blocked, then we fail to shootdown any inflight operations
potentially leaving the GPU spinning forever. As we only need to guard
the list against concurrent closures and insertions, the hold is short
and merits being treated as a simple spinlock.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMichael J. Ruhl <michael.j.ruhl@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200701084439.17025-1-chris@chris-wilson.co.uk

We don't need intel_dig_port and dig_port to refer to the same thing.
Prefer the latter.

v2: fix coding style
Signed-off-by: NLucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200626234834.26864-2-lucas.demarchi@intel.com

This registers will be used to implement PSR2 manual tracking/selective
fetch.

v2:
- Fixed typo in _PLANE_SEL_FETCH_BASE
- Renamed PSR2_MAN_TRK_CTL bits to better match spec names
- Renamed _PLANE_SEL_FETCH_* to better match spec names

BSpec: 55229
BSpec: 50424
BSpec: 50420
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Signed-off-by: NJosé Roberto de Souza <jose.souza@intel.com>
Reviewed-by: NGwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200626010151.221388-3-jose.souza@intel.com

Future patches will bring PSR2 selective fetch configuration
validation but most of the configuration checks will be used for HW
tracking and selective fetch so the reoder was necessary.
Reviewed-by: NGwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Signed-off-by: NJosé Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200626010151.221388-2-jose.souza@intel.com

This property will be used by PSR2 software tracking, adding it to
GEN12+.
Reviewed-by: NGwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Signed-off-by: NJosé Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200626010151.221388-1-jose.souza@intel.com

Rearrange the allocation of the mm_struct registration to avoid
allocating underneath the i915->mm_lock, so that we avoid tainting the
lock (and in turn many other locks that may be held as i915->mm_lock is
taken, and those locks we may want on the free [shrinker] paths). In
doing so, we convert the lookup to be RCU protected by courtesy of
converting the free-worker to be an rcu_work.

v2: Remember to use hash_rcu variants to protect the list iteration from
concurrent add/del.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200619194038.5088-1-chris@chris-wilson.co.uk

Often we seem to detect an underrun right after modeset on gen2.
It seems to be a spurious detection (potentially the pipe is still
in a wonky state when we enable the planes). An extra vblank wait
seems to cure it.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-13-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

The default fbc1 compression interval we use is 500 frames. That
translates to over 8 seconds typically. That's rather excessive
so let's drop it to 1 second.

The hardware will not attempt recompression unless at least one
line has been modified, so a shorter compression interval should
not cause extra bandwidth use in the purely idle scenario. Of
course in the mostly idle case we are possibly going to recompress
a bit more.

Should really try to find some kind of sweet spot to minimize
the energy usage...
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-11-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

Avoid the FBC_CONTROL rmw and just store the fbc compression
interval in the params/
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-10-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

Parametrize the FBC_CONTROL bits for neater code.

Also add the one missing bit: "stop compression on modification".
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-9-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

The hardware host tracking won't nuke the entire cfb (unless the
entire fb is written through the gtt) so don't clear the busy_bits
for gtt tracking.

Not that it really matters anymore since we've lost ORIGIN_GTT usage
everywhere.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-7-ville.syrjala@linux.intel.comReviewed-by: NJosé Roberto de Souza <jose.souza@intel.com>

The current fence_y_offset calculation is broken. I think it more or
less used to do the right thing, but then I changed the plane code
to put the final x/y source offsets back into the src rectangle so
now it's just subtraacting the same value from itself. The code would
never have worked if we allowed the framebuffer to have a non-zero
offset.

Let's do this in a better way by just calculating the fence_y_offset
from the final plane surface offset. Note that we don't align the
plane surface address to fence rows so with horizontal panning there's
often a horizontal offset from the fence start to the surface address
as well. We have no way to tell the hardware about that so we just
ignore it. Based on some quick tests the invlidation still happens
correctly. I presume due to the invalidation nuking at least the full
line (or a segment of multiple lines).

Fixes: 54d4d719 ("drm/i915: Overcome display engine stride limits via GTT remapping")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-4-ville.syrjala@linux.intel.comReviewed-by: NMatt Roper <matthew.d.roper@intel.com>

As we close a handle GEM object, we update the drm_file's idr with an
error^W NULL pointer to indicate the in-progress closure, and finally
removing it. If we read the idr directly, we may then see an invalid
object pointer, and in our debugfs per_file_stats() we therefore need
to protect against the entry being invalid.

[ 1016.651637] RIP: 0010:per_file_stats+0xe/0x16e
[ 1016.651646] Code: d2 41 0f b6 8e 69 8c 00 00 48 89 df 48 c7 c6 7b 74 8c be 31 c0 e8 0c 89 cf ff eb d2 0f 1f 44 00 00 55 48 89 e5 41
57 41 56 53 <8b> 06 85 c0 0f 84 4d 01 00 00 49 89 d6 48 89 f3 3d ff ff ff 7f 73
[ 1016.651651] RSP: 0018:ffffad3a01337ba0 EFLAGS: 00010293
[ 1016.651656] RAX: 0000000000000018 RBX: ffff96fe040d65e0 RCX: 0000000000000002
[ 1016.651660] RDX: ffffad3a01337c50 RSI: 0000000000000000 RDI: 00000000000001e8
[ 1016.651663] RBP: ffffad3a01337bb8 R08: 0000000000000000 R09: 00000000000001c0
[ 1016.651667] R10: 0000000000000000 R11: ffffffffbdbe5fce R12: 0000000000000000
[ 1016.651671] R13: ffffffffbdbe5fce R14: ffffad3a01337c50 R15: 0000000000000001
[ 1016.651676] FS:  00007a597e2d7480(0000) GS:ffff96ff3bb00000(0000) knlGS:0000000000000000
[ 1016.651680] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1016.651683] CR2: 0000000000000000 CR3: 0000000171fc2001 CR4: 00000000003606e0
[ 1016.651687] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1016.651690] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1016.651693] Call Trace:
[ 1016.651693] Call Trace:
[ 1016.651703]  idr_for_each+0x8a/0xe8
[ 1016.651711]  i915_gem_object_info+0x2a3/0x3eb
[ 1016.651720]  seq_read+0x162/0x3ca
[ 1016.651727]  full_proxy_read+0x5b/0x8d
[ 1016.651733]  __vfs_read+0x45/0x1bb
[ 1016.651741]  vfs_read+0xc9/0x15e
[ 1016.651746]  ksys_read+0x7e/0xde
[ 1016.651752]  do_syscall_64+0x54/0x68
[ 1016.651758]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Fixes: a8c15954 ("drm/i915: Protect debugfs per_file_stats with RCU lock")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200630152724.3734-1-chris@chris-wilson.co.uk