When CONFIG_DRM_XE_USERPTR_INVAL_INJECT=y, xe_pt_svm_userptr_pre_commit()
runs vma_check_userptr() with the svm notifier_lock taken for read. The
test injection causes vma_check_userptr() to call
xe_vma_userptr_force_invalidate(), which feeds into
xe_vma_userptr_do_inval() with drm_gpusvm_ctx.in_notifier=true. That
flag tells drm_gpusvm_unmap_pages() the caller already holds
notifier_lock for write and only asserts the mode. Because the caller
actually holds it for read, the assertion fires:
WARNING: drivers/gpu/drm/drm_gpusvm.c:1669 at \
drm_gpusvm_unmap_pages+0xd4/0x130 [drm_gpusvm_helper]
Call Trace:
xe_vma_userptr_do_inval+0x40d/0xfd0 [xe]
xe_vma_userptr_invalidate_pass1+0x3e6/0x8d0 [xe]
xe_vma_userptr_force_invalidate+0xde/0x290 [xe]
vma_check_userptr.constprop.0+0x1c6/0x220 [xe]
xe_pt_svm_userptr_pre_commit+0x6a3/0xc60 [xe]
...
xe_vm_bind_ioctl+0x3a0a/0x4480 [xe]
Acquire notifier_lock for write in pre-commit when the inject Kconfig
is enabled, via new helpers xe_pt_svm_userptr_notifier_lock()/_unlock().
Rename xe_svm_assert_held_read() to
xe_svm_assert_held_read_or_inject_write() so it asserts the correct
mode under each build configuration. Production builds
(CONFIG_DRM_XE_USERPTR_INVAL_INJECT=n) keep the existing read-mode
behavior bit-for-bit.
Fixes: 9e97874148 ("drm/xe/userptr: replace xe_hmm with gpusvm")
Assisted-by: Claude:claude-opus-4.7
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Zongyao Bai <zongyao.bai@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260625215615.3016892-1-shuicheng.lin@intel.com
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
Currently, xe_display_bo_framebuffer_init() unconditionally attempts to
apply XE_BO_FLAG_FORCE_WC to the buffer and rejects the FB creation with
-EINVAL if the BO is already VM_BINDed.
However, for imported dma-bufs (ttm_bo_type_sg), this check doesn't seem
to make much sense since CPU caching policy is entirely controlled by
the exporter. Plus there is no place to set this flag, in the first
place. Also this is not rejected if not yet vm_binded, but that seems
arbitrary since setting or not setting FORCE_WC should a noop either
way, at this stage, and whether it is currently VM_BINDed makes no
difference.
Currently if we run an app and offload rendering to an external dGPU,
like NV or another xe device, the dma-buf passed back to the compositor
(igpu) will be an actual external import from xe pov, and it will be
missing FORCE_WC, and if the compositor side did a VM_BIND before
turning into it into an fb the whole thing gets rejected.
So it looks like we either need to reject outright, no matter what, or
this usecase is valid and we need to loosen the restriction for sg
buffers. Proposing here to loosen the restriction.
Assisted-by: Gemini:gemini-3.1-pro-preview
Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/work_items/7919
Fixes: 44e694958b ("drm/xe/display: Implement display support")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Maarten Lankhorst <dev@lankhorst.se>
Cc: <stable@vger.kernel.org> # v6.12+
Reviewed-by: Maarten Lankhorst <dev@lankhorst.se>
Link: https://patch.msgid.link/20260612170501.550816-2-matthew.auld@intel.com
We shouldn't access device registers after the device was unplugged
or the MMIO bar (GTTMMADR) was unmapped. Instead of relying on the
NPD splat due to zeroed tile->mmio.regs, which might be unreliable
anyway as not all xe_mmio structs are using that directly, add an
explicit check during all xe_mmio read/write operations to test if
xe->mmio.regs are still mapped and safely abort with WARN if not.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patch.msgid.link/20260622132342.19600-2-michal.wajdeczko@intel.com
Whitelist OA registers on stream open and de-whitelist on stream
close/release. Whitelisting is only done when 'stream->sample' is
true. 'stream->sample' is only true when (a) xe_observation_paranoid is set
to false by system admin, or (b) the process is perfmon_capable(). This
therefore enforces the OA register whitelisting security requirements.
Fixes: 828a8eaf37 ("drm/xe/oa: Add MMIO trigger support")
Cc: stable@vger.kernel.org # v6.12+
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Link: https://patch.msgid.link/20260615224227.34880-9-ashutosh.dixit@intel.com
Now we can save OA whitelisting nonpriv registers to register save/restore
lists. OA nonpriv registers are saved to both hwe->oa_sr as well as
hwe->reg_sr.
During probe, resume and gt-reset flows KMD will apply hwe->reg_sr,
ensuring OA registers are de-whitelisted after these events. For
engine-reset, hwe->reg_sr is registered with GuC and GuC will apply these
registers, ensuring OA registers are de-whitelisted after engine resets.
hwe->oa_sr is used for whitelisting or de-whitelisting OA registers during
OA operation, by toggling the 'deny' bit on oa stream open/close.
Fixes: 828a8eaf37 ("drm/xe/oa: Add MMIO trigger support")
Cc: stable@vger.kernel.org # v6.12+
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Link: https://patch.msgid.link/20260615224227.34880-6-ashutosh.dixit@intel.com
The 'engine_sr' RTP table was allocated on the stack because it wasn't
truly constant and needed to calculate the proper value for
RING_CMD_CCTL at runtime based on other stack variables. Using the
FIELD_SET_FUNC action allows us to make the table itself truly constant
and move it off the stack; the RING_CMD_CCTL value is now calculated
during RTP table processing.
v2:
- Made table static
Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Link: https://patch.msgid.link/20260617-rtp_with_dynamic_vals-v2-4-3f4cb34c2ea1@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
The 'lrc_setup' RTP table was allocated on the stack because it wasn't
truly constant and needed to calculate the proper value for BLIT_CCTL at
runtime based on other stack variables. Using the FIELD_SET_FUNC action
allows us to make the table itself truly constant and move it off the
stack; the BLIT_CCTL value is now calculated during RTP table
processing.
v2:
- Made table static
Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Link: https://patch.msgid.link/20260617-rtp_with_dynamic_vals-v2-3-3f4cb34c2ea1@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Most of our RTP programming involves programming constant values into
register fields. However there are a few cases (e.g., RING_CMD_CCTL
programming) that rely on dynamic per-GT or per-engine checks to decide
what value will be programmed. Add a FIELD_SET_FUNC RTP action which
will call the provided function pointer once at RTP processing time to
determine the appropriate value.
v2:
- Tweak kerneldoc to avoid duplicating explanation from FIELD_SET.
(Gustavo)
Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Link: https://patch.msgid.link/20260617-rtp_with_dynamic_vals-v2-2-3f4cb34c2ea1@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
On DG2 the driver always shows two fan channels, because the
FSC_READ_NUM_FANS command does not work on some cards. OEMs decide how
the fans map to tach channels, so two fans can share one tach line.
When that happens, the second channel reads 0 RPM even though the fan
is spinning.
Note this on the fan2_input ABI entry so the steady 0 RPM is not
mistaken for a driver bug.
Fixes: 28f79ac609 ("drm/xe/hwmon: expose fan speed")
Signed-off-by: Zhan Wei <zhanwei919@gmail.com>
Reviewed-by: Raag Jadav <raag.jadav@intel.com>
Link: https://patch.msgid.link/20260602161707.18922-1-zhanwei919@gmail.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
The page-table walk framework may pass a NULL *child pointer for
unpopulated entries. xe_pt_zap_ptes_entry() called container_of(*child)
before checking for NULL, then dereferenced the result, causing a crash.
Move the container_of() call after a NULL guard, so the function returns
early instead of proceeding with an invalid pointer. XE_WARN_ON is kept
to help root cause the issue, but we now bail instead of crashing the
driver.
v2: Comment that triggering XE_WARN_ON is unexpected behavior (Matt Brost)
Fixes: dd08ebf6c3 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20260616081756.286918-1-francois.dugast@intel.com
Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Current implementation of generate_reclaim_entry() overlooks some
differences between the different page implementations: address masking
and compact 64K page handling.
Address masking of each leaf varies depending on the leaf entry size.
generate_reclaim_entry() is using XE_PTE_ADDR_MASK [51:12] for all leaf
entries. For 2MB PTEs, bit 12 (PAT) is part of the flags so the old mask
corrupts the physical address extraction.
64K pages can be represented as PS64 and a compact PT, which the latter
was not handled. Compact pages aren't walked by the unbind walker, so we
separately walk through the compact PT to ensure none of the leaf 64K
PTEs are dropped. Previously, compact PT were causing an abort since it
was considered covered and not descended into.
v2:
- Update 64K entry/unbind walker for 64K compact PT handling. (Matthew)
- Rework calculations of reclamation and address mask size.
- Add new func abstracting the error handling before generating the
reclaim entry.
v3:
- Report finer addr granularity in abort debug print for compact.
(Zongyao)
- Add comments for ADDR_MASK usage. (Zongyao)
- Drop existing phys_addr asserts, the new XE_PAGE_ADDR_MASK clears
bits checked, so redundant asserts. (Sashiko)
- WARN_ON to verify compact pt and edge pt won't be possible.
Fixes: b912138df2 ("drm/xe: Create page reclaim list on unbind")
Assisted-by: Sashiko-Review:gemini-3.1-pro-preview
Cc: stable@vger.kernel.org
Cc: Matthew Auld <matthew.auld@intel.com>
Suggested-by: Zongyao Bai <zongyao.bai@intel.com>
Signed-off-by: Brian Nguyen <brian3.nguyen@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Zongyao Bai <zongyao.bai@intel.com>
Link: https://patch.msgid.link/20260605224257.2194194-2-brian3.nguyen@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
The size calculation for the steered register extarray uses only the
geometry DSS mask (g_dss_mask) to determine the number of entries to
allocate:
total = bitmap_weight(gt->fuse_topo.g_dss_mask, ...) * steer_reg_num;
However, the filling loop uses for_each_dss_steering(), which iterates
over for_each_dss(), defined as the union of g_dss_mask and c_dss_mask
(geometry + compute DSS). On platforms with compute-only DSS bits, the
loop writes past the allocated buffer, corrupting adjacent slab objects.
This manifests as list_del corruption and SLUB redzone overwrites during
drm_managed_release on device unbind, since the overflow corrupts the
drmres list_head of neighboring allocations.
Fix by computing the allocation size using the union of both DSS masks,
matching the iteration pattern of for_each_dss_steering().
--
v2:
- use bitmap_weighted_or() (Zhanjun)
Fixes: b170d696c1 ("drm/xe/guc: Add XE_LP steered register lists")
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/8049
Cc: Zhanjun Dong <zhanjun.dong@intel.com>
Cc: stable@vger.kernel.org
Assisted-by: GitHub-Copilot:claude-opus-4.6
Reviewed-by: Zhanjun Dong <zhanjun.dong@intel.com>
Link: https://patch.msgid.link/20260612070401.543305-2-tejas.upadhyay@intel.com
Signed-off-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
Set the TTM device beneficial_order to 9 (2M), which is the sweet
spot for Xe when attempting reclaim on system memory BOs, as it matches
the large GPU page size. This ensures reclaim is attempted at the most
effective order for the driver.
This fixes an issue where an order-10 (4M) allocation cannot be found
despite an abundance of memory. The 4M allocation triggers reclaim,
unnecessarily evicting the working set and hurting performance. Since
the TTM infrastructure was introduced recently, we are tagging the TTM
patch as the Fixes target, even though this resolves an Xe-side problem.
Fixes: 7e9c548d37 ("drm/ttm: Allow drivers to specify maximum beneficial TTM pool size")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patch.msgid.link/20260611235844.3725147-1-matthew.brost@intel.com
A kernel job that exhausts its recovery attempts called
xe_device_declare_wedged() directly from guc_exec_queue_timedout_job(),
while the handler still owned the timed-out job and the queue scheduler
(sched = &q->guc->sched, stopped at the top of the handler).
In the default wedged mode (XE_WEDGED_MODE_UPON_CRITICAL_ERROR),
xe_device_declare_wedged() takes the destructive path in
xe_guc_submit_wedge(): guc_submit_reset_prepare(), xe_guc_submit_stop()
- which calls guc_exec_queue_stop() on every queue, including this one -
softreset and pause-abort. That tears submission down, signals the
in-flight fences and restarts the schedulers. This is the correct
behaviour when the wedge originates outside the TDR, but not when the
TDR itself triggers it: every queue should be torn down except the one
the TDR is currently operating on, which it still owns.
Control then returned to the handler, which kept using the now stale job
and scheduler:
xe_sched_job_set_error(job, err);
drm_sched_for_each_pending_job(tmp_job, &sched->base, NULL)
xe_sched_job_set_error(to_xe_sched_job(tmp_job), -ECANCELED);
drm_sched_for_each_pending_job() warns because the scheduler is no
longer stopped (WARN_ON(!drm_sched_is_stopped())) and the iteration then
dereferences a freed job, faulting on the slab poison:
Oops: general protection fault ... 0x6b6b6b6b6b6b6c3b
RIP: guc_exec_queue_timedout_job+...
Defer the wedge until the handler has finished operating on the queue,
right before returning DRM_GPU_SCHED_STAT_NO_HANG, so the teardown no
longer races with this handler's use of @q.
Fixes: b1107d085e ("drm/xe: fix job timeout recovery for unstarted jobs and kernel queues")
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Cc: Sanjay Yadav <sanjay.kumar.yadav@intel.com>
Assisted-by: GitHub-Copilot:claude-opus-4.8
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260612162414.287971-2-rodrigo.vivi@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Sometimes the same workaround implementation ends up being the
recommended fix different hardware issues, which are tracked by
different workaround lineage numbers.
Some of the Xe3p_LPG workarounds got "dismissed" because the
implementations were already in the driver, however for a different
lineage number.
Even though the implementation for workaround #A is already present in
the driver for workaround #B, it is still important to reference #A in
the driver for tracking purposes. Without such a reference, we risk
dropping the workaround implementation if, for some reason in the
future, we decide that #B is not necessary anymore while #A is still
required.
As such, add the missing references for Xe3p_LPG.
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patch.msgid.link/20260610-add-missing-wa-references-v1-1-0947577238bf@intel.com
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
When building with 'make M=drivers/gpu/drm/xe modules', kbuild invokes
scripts/Makefile.build with obj=., causing $(obj) to expand to '.'.
Make normalizes './xe_gen_wa_oob' to 'xe_gen_wa_oob' when constructing
the $^ automatic variable (target name normalization), so the recipe
command becomes just 'xe_gen_wa_oob ...' without any path prefix, and
the shell cannot find the tool.
Fix by replacing $^ with explicit $(obj)/xe_gen_wa_oob and
$(src)/<rules-file> references in both wa_oob recipe commands.
In recipe strings, make does not apply target name normalization, so
$(obj)/xe_gen_wa_oob correctly expands to './xe_gen_wa_oob' and the
shell can execute it. This matches the pattern already used by other
DRM drivers (e.g. radeon's mkregtable).
Fixes: f037e0b78e ("drm/xe: add xe_device_wa infrastructure")
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: intel-xe@lists.freedesktop.org
Assisted-by: GitHub_Copilot:claude-sonnet-4.6
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20260604074501.172129-1-thomas.hellstrom@linux.intel.com
Fixes the following warning that fires during timeout handling for a
context running on the USM-reserved copy engine:
xe 0000:03:00.0: [drm] Tile0: GT0: Unexpected engine class:instance 3:8 for utilization
WARNING: at engine_id_to_hwe+0x88/0xc0 [xe]
xe_lrc_context_timestamp+0x61/0xb0 [xe]
guc_exec_queue_timedout_job+0x713/0x1020 [xe]
class:instance 3:8 is XE_ENGINE_CLASS_COPY on the highest BCS instance,
which xe_hw_engine.c reserves for USM (gt->usm.reserved_bcs_instance) and
on which the migrate engine runs kernel contexts. When such a context's
utilization is read - e.g. from the TDR path - engine_id_to_hwe()
rejected it because xe_hw_engine_is_reserved() is true, firing WARN_ONCE
and returning NULL, which made the timestamp read silently fall back to
stale data.
The reserved-engine guard was added defensively with the original WA BB
utilization support and simply overlooked that the migrate engine is a
valid, present engine whose CTX_TIMESTAMP can legitimately be read.
Allow the USM-reserved copy engine specifically (xe_gt_is_usm_hwe()),
while still rejecting the other reserved cases (GSCCS / XE_ENGINE_CLASS_
OTHER and ccs_mode-disabled compute engines), which would indeed be
unexpected on this path. The dynamic engine resolution via the ENGINE_ID
stashed in the PPHWSP by the WA BB is kept intact, so utilization for
load-balanced/virtual exec queues still resolves the engine the context
is actually running on.
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Sanjay Yadav <sanjay.kumar.yadav@intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Assisted-by: GitHub-Copilot:claude-sonnet-4.6
Assisted-by: GitHub-Copilot:claude-opus-4.8
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patch.msgid.link/20260610152548.404575-4-rodrigo.vivi@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
A job that GuC never scheduled (never started) indicates a GuC
scheduling failure; previously such jobs were silently errored out
instead of triggering a GT reset to recover. Trigger a GT reset and
resubmit them, but only when the queue was not already killed or banned:
an unstarted job on an already banned queue is the ban working as
intended and must neither clear the ban nor kick off a reset, otherwise
a banned userspace queue could be resurrected and spam GT resets.
Kernel queues are always recovered this way and wedge the device once
recovery attempts are exhausted, since kernel work must not silently
fail. A started job that times out on a userspace VM bind queue stays
banned rather than being reset and retried.
The queue is banned early in the timeout handler to signal the G2H
scheduling-done handler so it wakes the disable-scheduling waiter;
without it the waiter sleeps the full 5s timeout. When a reset is
warranted the ban is cleared before rearming so that
guc_exec_queue_start() can resubmit jobs after the GT reset - a
still-banned queue would block resubmission and cause an infinite TDR
loop. The already-banned case is gated out before this point via
skip_timeout_check, so it is unaffected.
v2: (Himal) Do it for any queue type, not just kernel/migration
v3: - (Sashiko and Sanjay): don't clear the ban / GT reset for already
killed/banned queues on unstarted-job timeout
- Update commit message
- (Matt) Add Fixes tag
Fixes: fe05cee4d9 ("drm/xe: Don't short circuit TDR on jobs not started")
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Sanjay Yadav <sanjay.kumar.yadav@intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Assisted-by: GitHub-Copilot:claude-sonnet-4.6
Assisted-by: GitHub-Copilot:claude-opus-4.8
Tested-by: Sanjay Yadav <sanjay.kumar.yadav@intel.com>
Reviewed-by: Sanjay Yadav <sanjay.kumar.yadav@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patch.msgid.link/20260610152548.404575-3-rodrigo.vivi@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Purgeable state updates only change VMA/BO metadata. They do not zap
PTEs when switching between DONTNEED and WILLNEED. PTEs are zapped
later if the BO is actually purged.
xe_vm_invalidate_madvise_range() waits on the VM dma-resv before checking
vma->skip_invalidation. Since purgeable madvise marks all affected VMAs to
skip invalidation, this wait is unnecessary and can stall on unrelated
in-flight work.
Skip the invalidate path entirely for purgeable state updates.
v2:
- Replace inline 'args->type != DRM_XE_VMA_ATTR_PURGEABLE_STATE'
check with a small helper madvise_range_needs_invalidation().
(Himal)
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Signed-off-by: Arvind Yadav <arvind.yadav@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patch.msgid.link/20260526135447.2973029-1-arvind.yadav@intel.com
Signed-off-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
xe_range_fence_insert() acquires a reference on fence via
dma_fence_get() and stores it in rfence->fence. It then calls
dma_fence_add_callback() and handles two cases: when the callback
is successfully registered (err == 0) the fence is transferred to
the tree for later cleanup; when the fence is already signaled
(err == -ENOENT) it manually drops the extra reference with
dma_fence_put(fence).
However, dma_fence_add_callback() can fail with other errors
(e.g. -EINVAL) and in that case the code falls through to the free:
label without releasing the acquired reference, leaking it.
Fix the leak by adding an else branch that calls dma_fence_put()
before jumping to free: for any error other than -ENOENT.
Fixes: 845f64bdbf ("drm/xe: Introduce a range-fence utility")
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260610172705.3450560-1-matthew.brost@intel.com
Context-based TLB invalidation currently selects only scheduling-active
exec queues via q->ops->active(). During rebind flows, queues may be
suspended (or transitioning through resume) while still owning valid
translations, causing them to be skipped from invalidation and leading
to missed TLB invalidations on LR rebinds.
The underlying issue is a TOCTOU: q->guc->state bits are flipped lock-free
from enable_scheduling(), disable_scheduling{,_deregister}(), the
suspend/resume sched-msg handlers, handle_sched_done(), and
guc_exec_queue_stop(); nothing in send_tlb_inval_ctx_ppgtt() serializes
against them, so any state-based predicate can race.
Include all the registered queues so that TLB invalidations are not
missed. This is race-free because list membership on vm->exec_queues.list
is stable under vm->exec_queues.lock held by the caller. The performance
impact is expected to be minimal and harmless. If it does turn out to be
a concern, we can come back with a race-safe solution to ignore certain
queues.
Fixes: 6cdaa5346d ("drm/xe: Add context-based invalidation to GuC TLB invalidation backend")
Assisted-by: Claude:claude-opus-4.6
Suggested-by: Thomas Hellstrom <thomas.hellstrom@linux.intel.com>
Signed-off-by: Tangudu Tilak Tirumalesh <tilak.tirumalesh.tangudu@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260608162745.338725-2-tilak.tirumalesh.tangudu@intel.com
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
