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  1. 24 1月, 2020 1 次提交
  3. 23 1月, 2020 1 次提交
  5. 09 1月, 2020 1 次提交
  7. 08 1月, 2020 1 次提交
  9. 24 12月, 2019 1 次提交
  11. 23 12月, 2019 1 次提交
  13. 22 12月, 2019 1 次提交
  15. 20 12月, 2019 2 次提交
  17. 18 12月, 2019 1 次提交
  19. 07 12月, 2019 1 次提交
    • C
      drm/i915/gem: Pin gen6_ppgtt prior to constructing the request · aef82079
      由 Chris Wilson 提交于 
      All pinning must be done prior to i915_request_create, to avoid
timeline->mutex inversions.

Here we slightly abuse the context_barrier_task stages to utilise the
'skip' decision as an opportunity to acquire the pin on the new ppgtt.
Consider it s/skip/prepare/. At the moment, we only have on user of
context_barrier_task, so it might be worth breaking it down for the
specific task of set-vm and refactor it later if we find a second
purpose.

<4> [402.377487] WARNING: possible circular locking dependency detected
<4> [402.377493] 5.4.0-rc8-CI-CI_DRM_7491+ #1 Tainted: G     U
<4> [402.377497] ------------------------------------------------------
<4> [402.377502] gem_exec_parall/2506 is trying to acquire lock:
<4> [402.377507] ffff888403cdac70 (&kernel#2){+.+.}, at: i915_request_create+0x16/0x1c0 [i915]
<4> [402.377593]
but task is already holding lock:
<4> [402.377597] ffff88835efad550 (&ppgtt->pin_mutex){+.+.}, at: gen6_ppgtt_pin+0x4d/0x110 [i915]
<4> [402.377660]
which lock already depends on the new lock.

<4> [402.377664]
the existing dependency chain (in reverse order) is:
<4> [402.377668]
-> #1 (&ppgtt->pin_mutex){+.+.}:
<4> [402.377674]        __mutex_lock+0x9a/0x9d0
<4> [402.377713]        gen6_ppgtt_pin+0x4d/0x110 [i915]
<4> [402.377756]        emit_ppgtt_update+0x1dc/0x370 [i915]
<4> [402.377801]        context_barrier_task+0x176/0x310 [i915]
<4> [402.377844]        ctx_setparam+0x400/0xb10 [i915]
<4> [402.377886]        i915_gem_context_setparam_ioctl+0xc8/0x160 [i915]
<4> [402.377891]        drm_ioctl_kernel+0xa7/0xf0
<4> [402.377895]        drm_ioctl+0x2e1/0x390
<4> [402.377899]        do_vfs_ioctl+0xa0/0x6f0
<4> [402.377903]        ksys_ioctl+0x35/0x60
<4> [402.377906]        __x64_sys_ioctl+0x11/0x20
<4> [402.377910]        do_syscall_64+0x4f/0x210
<4> [402.377914]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4> [402.377917]
-> #0 (&kernel#2){+.+.}:
<4> [402.377923]        __lock_acquire+0x1328/0x15d0
<4> [402.377926]        lock_acquire+0xa7/0x1c0
<4> [402.377930]        __mutex_lock+0x9a/0x9d0
<4> [402.377977]        i915_request_create+0x16/0x1c0 [i915]
<4> [402.378013]        intel_engine_flush_barriers+0x4c/0x100 [i915]
<4> [402.378062]        i915_ggtt_pin+0x7d/0x130 [i915]
<4> [402.378108]        gen6_ppgtt_pin+0x9c/0x110 [i915]
<4> [402.378148]        ring_context_pin+0x2e/0xc0 [i915]
<4> [402.378183]        __intel_context_do_pin+0x6b/0x190 [i915]
<4> [402.378226]        i915_gem_do_execbuffer+0x180c/0x26b0 [i915]
<4> [402.378268]        i915_gem_execbuffer2_ioctl+0x11b/0x460 [i915]
<4> [402.378272]        drm_ioctl_kernel+0xa7/0xf0
<4> [402.378275]        drm_ioctl+0x2e1/0x390
<4> [402.378279]        do_vfs_ioctl+0xa0/0x6f0
<4> [402.378282]        ksys_ioctl+0x35/0x60
<4> [402.378286]        __x64_sys_ioctl+0x11/0x20
<4> [402.378289]        do_syscall_64+0x4f/0x210
<4> [402.378292]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4> [402.378295]
other info that might help us debug this:

<4> [402.378299]  Possible unsafe locking scenario:

<4> [402.378302]        CPU0                    CPU1
<4> [402.378305]        ----                    ----
<4> [402.378307]   lock(&ppgtt->pin_mutex);
<4> [402.378310]                                lock(&kernel#2);
<4> [402.378314]                                lock(&ppgtt->pin_mutex);
<4> [402.378317]   lock(&kernel#2);
<4> [402.378320]
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/20191206105527.1130413-4-chris@chris-wilson.co.uk
      aef82079
  21. 02 12月, 2019 1 次提交
  23. 30 11月, 2019 1 次提交
  25. 28 11月, 2019 1 次提交
  27. 25 11月, 2019 1 次提交
  29. 18 11月, 2019 1 次提交
  31. 16 11月, 2019 1 次提交
  33. 13 11月, 2019 1 次提交
  35. 11 11月, 2019 3 次提交
  37. 08 11月, 2019 1 次提交
  39. 06 11月, 2019 2 次提交
    • C
      drm/i915/gem: Fix error path to unlock if the GEM context is closed · feba2b81
      由 Chris Wilson 提交于 
      When inside the lock, remember to unlock even if you want to leave
early.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Fixes: a4e7ccda ("drm/i915: Move context management under GEM")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191106144155.25727-1-chris@chris-wilson.co.uk
      feba2b81
    • J
      drm/i915/cmdparser: Add support for backward jumps · f8c08d8f
      由 Jon Bloomfield 提交于 
      To keep things manageable, the pre-gen9 cmdparser does not
attempt to track any form of nested BB_START's. This did not
prevent usermode from using nested starts, or even chained
batches because the cmdparser is not strictly enforced pre gen9.

Instead, the existence of a nested BB_START would cause the batch
to be emitted in insecure mode, and any privileged capabilities
would not be available.

For Gen9, the cmdparser becomes mandatory (for BCS at least), and
so not providing any form of nested BB_START support becomes
overly restrictive. Any such batch will simply not run.

We make heavy use of backward jumps in igt, and it is much easier
to add support for this restricted subset of nested jumps, than to
rewrite the whole of our test suite to avoid them.

Add the required logic to support limited backward jumps, to
instructions that have already been validated by the parser.

Note that it's not sufficient to simply approve any BB_START
that jumps backwards in the buffer because this would allow an
attacker to embed a rogue instruction sequence within the
operand words of a harmless instruction (say LRI) and jump to
that.

We introduce a bit array to track every instr offset successfully
validated, and test the target of BB_START against this. If the
target offset hits, it is re-written to the same offset in the
shadow buffer and the BB_START cmd is allowed.

Note: This patch deliberately ignores checkpatch issues in the
cmdtables, in order to match the style of the surrounding code.
We'll correct the entire file in one go in a later patch.

v2: set dispatch secure late (Mika)
v3: rebase (Mika)
v4: Clear whitelist on each parse
    Minor review updates (Chris)
v5: Correct backward jump batching
v6: fix compilation error due to struct eb shuffle (Mika)

Cc: Tony Luck <tony.luck@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: NJon Bloomfield <jon.bloomfield@intel.com>
Signed-off-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NChris Wilson <chris.p.wilson@intel.com>
      f8c08d8f
  41. 01 11月, 2019 1 次提交
  43. 30 10月, 2019 2 次提交
    • P
      drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer() · 1feace5d
      由 Paul E. McKenney 提交于 
      This commit replaces the use of rcu_swap_protected() with the more
intuitively appealing rcu_replace_pointer() as a step towards removing
rcu_swap_protected().

Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
[ paulmck: From rcu_replace() to rcu_replace_pointer() per Ingo Molnar. ]
Signed-off-by: NPaul E. McKenney <paulmck@kernel.org>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <intel-gfx@lists.freedesktop.org>
Cc: <dri-devel@lists.freedesktop.org>
      1feace5d
    • C
      drm/i915/gem: Make context persistence optional · a0e04715
      由 Chris Wilson 提交于 
      Our existing behaviour is to allow contexts and their GPU requests to
persist past the point of closure until the requests are complete. This
allows clients to operate in a 'fire-and-forget' manner where they can
setup a rendering pipeline and hand it over to the display server and
immediately exit. As the rendering pipeline is kept alive until
completion, the display server (or other consumer) can use the results
in the future and present them to the user.

The compute model is a little different. They have little to no buffer
sharing between processes as their kernels tend to operate on a
continuous stream, feeding the results back to the client application.
These kernels operate for an indeterminate length of time, with many
clients wishing that the kernel was always running for as long as they
keep feeding in the data, i.e. acting like a DSP.

Not all clients want this persistent "desktop" behaviour and would prefer
that the contexts are cleaned up immediately upon closure. This ensures
that when clients are run without hangchecking (e.g. for compute kernels
of indeterminate runtime), any GPU hang or other unexpected workloads
are terminated with the process and does not continue to hog resources.

The default behaviour for new contexts is the legacy persistence mode,
as some desktop applications are dependent upon the existing behaviour.
New clients will have to opt in to immediate cleanup on context
closure. If the hangchecking modparam is disabled, so is persistent
context support -- all contexts will be terminated on closure.

We expect this behaviour change to be welcomed by compute users, who
have often been caught between a rock and a hard place. They disable
hangchecking to avoid their kernels being "unfairly" declared hung, but
have also experienced true hangs that the system was then unable to
clean up. Naturally, this leads to bug reports.

Testcase: igt/gem_ctx_persistence
Link: https://github.com/intel/compute-runtime/pull/228Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: NJon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: NJason Ekstrand <jason@jlekstrand.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20191029202338.8841-1-chris@chris-wilson.co.uk
      a0e04715
  45. 26 10月, 2019 1 次提交
  47. 24 10月, 2019 2 次提交
  49. 18 10月, 2019 1 次提交
  51. 04 10月, 2019 6 次提交
  53. 25 9月, 2019 1 次提交
  55. 20 9月, 2019 1 次提交
    • C
      drm/i915: Mark i915_request.timeline as a volatile, rcu pointer · d19d71fc
      由 Chris Wilson 提交于 
      The request->timeline is only valid until the request is retired (i.e.
before it is completed). Upon retiring the request, the context may be
unpinned and freed, and along with it the timeline may be freed. We
therefore need to be very careful when chasing rq->timeline that the
pointer does not disappear beneath us. The vast majority of users are in
a protected context, either during request construction or retirement,
where the timeline->mutex is held and the timeline cannot disappear. It
is those few off the beaten path (where we access a second timeline) that
need extra scrutiny -- to be added in the next patch after first adding
the warnings about dangerous access.

One complication, where we cannot use the timeline->mutex itself, is
during request submission onto hardware (under spinlocks). Here, we want
to check on the timeline to finalize the breadcrumb, and so we need to
impose a second rule to ensure that the request->timeline is indeed
valid. As we are submitting the request, it's context and timeline must
be pinned, as it will be used by the hardware. Since it is pinned, we
know the request->timeline must still be valid, and we cannot submit the
idle barrier until after we release the engine->active.lock, ergo while
submitting and holding that spinlock, a second thread cannot release the
timeline.

v2: Don't be lazy inside selftests; hold the timeline->mutex for as long
as we need it, and tidy up acquiring the timeline with a bit of
refactoring (i915_active_add_request)
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190919111912.21631-1-chris@chris-wilson.co.uk
      d19d71fc
  57. 03 9月, 2019 1 次提交