If we have a set of active engines marked as being non-persistent, we
lose track of those if the user replaces those engines with
I915_CONTEXT_PARAM_ENGINES. As part of our uABI contract is that
non-persistent requests are terminated if they are no longer being
tracked by the user's context (in order to prevent a lost request
causing an untracked and so unstoppable GPU hang), we need to apply the
same context cancellation upon changing engines.
v2: Track stale engines[] so we only reap at context closure.
v3: Tvrtko spotted races with closing contexts and set-engines, so add a
veneer of kill-everything paranoia to clean up after losing a race.
Fixes: a0e047156c ("drm/i915/gem: Make context persistence optional")
Testcase: igt/gem_ctx_peristence/replace
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/20200211144831.1011498-1-chris@chris-wilson.co.uk
To enable non-persistent contexts, we require a means of cancelling any
inflight work from that context. This is first done "gracefully" by
using preemption to kick the active context off the engine, and then
forcefully by resetting the engine if it is active. If we are unable to
reset the engine to remove hostile userspace, we should not allow
userspace to opt into using non-persistent contexts.
If the per-engine reset fails, we still do a full GPU reset, but that is
rare and usually indicative of much deeper issues. The damage is already
done. However, the goal of the interface to allow long running compute
jobs without causing collateral damage elsewhere, and if we are unable
to support that we should make that known by not providing the
interface (and falsely pretending we can).
Fixes: a0e047156c ("drm/i915/gem: Make context persistence optional")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200130164553.1937718-1-chris@chris-wilson.co.uk
Allocate only an internal intel_context for the kernel_context, forgoing
a global GEM context for internal use as we only require a separate
address space (for our own protection).
Now having weaned GT from requiring ce->gem_context, we can stop
referencing it entirely. This also means we no longer have to create random
and unnecessary GEM contexts for internal use.
GEM contexts are now entirely for tracking GEM clients, and intel_context
the execution environment on the GPU.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Acked-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191221160324.1073045-1-chris@chris-wilson.co.uk
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: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191206105527.1130413-4-chris@chris-wilson.co.uk
Pull more drm updates from Dave Airlie:
"Rob pointed out I missed his pull request for msm-next, it's been in
next for a while outside of my tree so shouldn't cause any unexpected
issues, it has some OCMEM support in drivers/soc that is acked by
other maintainers as it's outside my tree.
Otherwise it's a usual fixes pull, i915, amdgpu, the main ones, with
some tegra, omap, mgag200 and one core fix.
Summary:
msm-next:
- OCMEM support for a3xx and a4xx GPUs.
- a510 support + display support
core:
- mst payload deletion fix
i915:
- uapi alignment fix
- fix for power usage regression due to security fixes
- change default preemption timeout to 640ms from 100ms
- EHL voltage level display fixes
- TGL DGL PHY fix
- gvt - MI_ATOMIC cmd parser fix, CFL non-priv warning
- CI spotted deadlock fix
- EHL port D programming fix
amdgpu:
- VRAM lost fixes on BACO for CI/VI
- navi14 DC fixes
- misc SR-IOV, gfx10 fixes
- XGMI fixes for arcturus
- SRIOV fixes
amdkfd:
- KFD on ppc64le enabled
- page table optimisations
radeon:
- fix for r1xx/2xx register checker.
tegra:
- displayport regression fixes
- DMA API regression fixes
mgag200:
- fix devices that can't scanout except at 0 addr
omap:
- fix dma_addr refcounting"
* tag 'drm-next-2019-12-06' of git://anongit.freedesktop.org/drm/drm: (100 commits)
drm/dp_mst: Correct the bug in drm_dp_update_payload_part1()
drm/omap: fix dma_addr refcounting
drm/tegra: Run hub cleanup on ->remove()
drm/tegra: sor: Make the +5V HDMI supply optional
drm/tegra: Silence expected errors on IOMMU attach
drm/tegra: vic: Export module device table
drm/tegra: sor: Implement system suspend/resume
drm/tegra: Use proper IOVA address for cursor image
drm/tegra: gem: Remove premature import restrictions
drm/tegra: gem: Properly pin imported buffers
drm/tegra: hub: Remove bogus connection mutex check
ia64: agp: Replace empty define with do while
agp: Add bridge parameter documentation
agp: remove unused variable num_segments
agp: move AGPGART_MINOR to include/linux/miscdevice.h
agp: remove unused variable size in agp_generic_create_gatt_table
drm/dp_mst: Fix build on systems with STACKTRACE_SUPPORT=n
drm/radeon: fix r1xx/r2xx register checker for POT textures
drm/amdgpu: fix GFX10 missing CSIB set(v3)
drm/amdgpu: should stop GFX ring in hw_fini
...
One does not lightly add a new hidden struct_mutex dependency deep within
the execbuf bowels! The immediate suspicion in seeing the whitelist
cached on the context, is that it is intended to be preserved between
batches, as the kernel is quite adept at caching small allocations
itself. But no, it's sole purpose is to serialise command submission in
order to save a kmalloc on a slow, slow path!
By removing the whitelist dependency from the context, our freedom to
chop the big struct_mutex is greatly augmented.
v2: s/set_bit/__set_bit/ as the whitelist shall never be accessed
concurrently.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191128113424.3885958-1-chris@chris-wilson.co.uk
Pull drm updates from Dave Airlie:
"Lots of stuff in here, though it hasn't been too insane this merge
apart from dealing with the security fun.
uapi:
- export different colorspace properties on DP vs HDMI
- new fourcc for ARM 16x16 block format
- syncobj: allow querying last submitted timeline value
- DRM_FORMAT_BIG_ENDIAN defined as unsigned
core:
- allow using gem vma manager in ttm
- connector/encoder/bridge doc fixes
- allow more than 3 encoders for a connector
- displayport mst suspend/resume reprobing support
- vram lazy unmapping, uniform vram mm and gem vram
- edid cleanups + AVI informframe bar info
- displayport helpers - dpcd parser added
dp_cec:
- Allow a connector to be associated with a cec device
ttm:
- pipelining with no_gpu_wait fix
- always keep BOs on the LRU
sched:
- allow free_job routine to sleep
i915:
- Block userptr from mappable GTT
- i915 perf uapi versioning
- OA stream dynamic reconfiguration
- make context persistence optional
- introduce DRM_I915_UNSTABLE Kconfig
- add fake lmem testing under unstable
- BT.2020 support for DP MSA
- struct mutex elimination
- Tigerlake display/PLL/power management improvements
- Jasper Lake PCH support
- refactor PMU for multiple GPUs
- Icelake firmware update
- Split out vga + switcheroo code
amdgpu:
- implement dma-buf import/export without helpers
- vega20 RAS enablement
- DC i2c over aux fixes
- renoir GPU reset
- DC HDCP support
- BACO support for CI/VI asics
- MSI-X support
- Arcturus EEPROM support
- Arcturus VCN encode support
- VCN dynamic powergating on RV/RV2
amdkfd:
- add navi12/14/renoir support to kfd
radeon:
- SI dpm fix ported from amdgpu
- fix bad DMA on ppc platforms
gma500:
- memory leak fixes
qxl:
- convert to new gem mmap
exynos:
- build warning fix
komeda:
- add aclk sysfs attribute
v3d:
- userspace cleanup uapi change
i810:
- fix for underflow in dispatch ioctls
ast:
- refactor show_cursor
mgag200:
- refactor show_cursor
arcgpu:
- encoder finding improvements
mediatek:
- mipi_tx, dsi and partial crtc support for MT8183 SoC
- rotation support
meson:
- add suspend/resume support
omap:
- misc refactors
tegra:
- DisplayPort support for Tegra 210, 186 and 194.
- IOMMU-backed DMA API fixes
panfrost:
- fix lockdep issue
- simplify devfreq integration
rcar-du:
- R8A774B1 SoC support
- fixes for H2 ES2.0
sun4i:
- vcc-dsi regulator support
virtio-gpu:
- vmexit vs spinlock fix
- move to gem shmem helpers
- handle large command buffers with cma"
* tag 'drm-next-2019-11-27' of git://anongit.freedesktop.org/drm/drm: (1855 commits)
drm/amdgpu: invalidate mmhub semaphore workaround in gmc9/gmc10
drm/amdgpu: initialize vm_inv_eng0_sem for gfxhub and mmhub
drm/amd/amdgpu/sriov skip RLCG s/r list for arcturus VF.
drm/amd/amdgpu/sriov temporarily skip ras,dtm,hdcp for arcturus VF
drm/amdgpu/gfx10: re-init clear state buffer after gpu reset
merge fix for "ftrace: Rework event_create_dir()"
drm/amdgpu: Update Arcturus golden registers
drm/amdgpu/gfx10: fix out-of-bound mqd_backup array access
drm/amdgpu/gfx10: explicitly wait for cp idle after halt/unhalt
Revert "drm/amd/display: enable S/G for RAVEN chip"
drm/amdgpu: disable gfxoff on original raven
drm/amdgpu: remove experimental flag for Navi14
drm/amdgpu: disable gfxoff when using register read interface
drm/amdgpu/powerplay: properly set PP_GFXOFF_MASK (v2)
drm/amdgpu: fix bad DMA from INTERRUPT_CNTL2
drm/radeon: fix bad DMA from INTERRUPT_CNTL2
drm/amd/display: Fix debugfs on MST connectors
drm/amdgpu/nv: add asic func for fetching vbios from rom directly
drm/amdgpu: put flush_delayed_work at first
drm/amdgpu/vcn2.5: fix the enc loop with hw fini
...
Pull RCU updates from Ingo Molnar:
"The main changes in this cycle were:
- Dynamic tick (nohz) updates, perhaps most notably changes to force
the tick on when needed due to lengthy in-kernel execution on CPUs
on which RCU is waiting.
- Linux-kernel memory consistency model updates.
- Replace rcu_swap_protected() with rcu_prepace_pointer().
- Torture-test updates.
- Documentation updates.
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()
net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
net/netfilter: Replace rcu_swap_protected() with rcu_replace_pointer()
net/core: Replace rcu_swap_protected() with rcu_replace_pointer()
bpf/cgroup: Replace rcu_swap_protected() with rcu_replace_pointer()
fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
drivers/scsi: Replace rcu_swap_protected() with rcu_replace_pointer()
drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer()
x86/kvm/pmu: Replace rcu_swap_protected() with rcu_replace_pointer()
rcu: Upgrade rcu_swap_protected() to rcu_replace_pointer()
rcu: Suppress levelspread uninitialized messages
rcu: Fix uninitialized variable in nocb_gp_wait()
rcu: Update descriptions for rcu_future_grace_period tracepoint
rcu: Update descriptions for rcu_nocb_wake tracepoint
rcu: Remove obsolete descriptions for rcu_barrier tracepoint
rcu: Ensure that ->rcu_urgent_qs is set before resched IPI
workqueue: Convert for_each_wq to use built-in list check
rcu: Several rcu_segcblist functions can be static
rcu: Remove unused function hlist_bl_del_init_rcu()
Documentation: Rename rcu_node_context_switch() to rcu_note_context_switch()
...
As the engine->kernel_context is used within the engine-pm barrier, we
have to be careful when emitting requests outside of the barrier, as the
strict timeline locking rules do not apply. Instead, we must ensure the
engine_park() cannot be entered as we build the request, which is
simplest by taking an explicit engine-pm wakeref around the request
construction.
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/20191125105858.1718307-1-chris@chris-wilson.co.uk
Backmerge to get dfce90259d ("Backmerge i915 security patches from
commit 'ea0b163b13ff' into drm-next") and thus 100d46bd72 ("Merge
Intel Gen8/Gen9 graphics fixes from Jon Bloomfield.").
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
- PMU "Frequency" is reported as accumulated cycles
- Avoid OOPS in dumb_create IOCTL when no CRTCs
- Mitigation for userptr put_pages deadlock with trylock_page
- Fix to avoid freeing heartbeat request too early
- Fix LRC coherency issue
- Fix Bugzilla #112212: Avoid screen corruption on MST
- Error path fix to unlock context on failed context VM SETPARAM
- Always consider holding preemption a privileged op in perf/OA
- Preload LUTs if the hw isn't currently using them to avoid color flash on VLV/CHV
- Protect context while grabbing its name for the request
- Don't resize aliasing ppGTT size
- Smaller fixes picked by tooling
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191114085213.GA6440@jlahtine-desk.ger.corp.intel.com
This backmerges the branch that ended up in Linus' tree. It removes
all the changes for the rc6 patches from Linus' tree in favour of
a patch that is based on a large refactor that occured.
Otherwise it all looks good.
Signed-off-by: Dave Airlie <airlied@redhat.com>
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: Jon Bloomfield <jon.bloomfield@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris.p.wilson@intel.com>
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/228
Signed-off-by: Chris 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: Jon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20191029202338.8841-1-chris@chris-wilson.co.uk
