kbuild: rust: keep Rust objects out of Clang LTO with inline helpersgrafted

Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit
`objtool` errors such as:

    vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a:
    can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd

The reason is that in such builds, the Clang invocation that compiles
the combined Rust plus helpers bitcode emits LLVM bitcode (again) --
the final code generation happens in the linker's LTO step, which the
`-mllvm` trap options passed to Clang do not reach.

This, in turn, means that unreachable traps are missing, and the
impossible paths do not merely fallthrough to the next symbol, but past
the end of their own section, since LTO builds place each function in
its own section.

Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always
emits machine code directly, with the traps in place.

Assisted-by: LLM
Cc: Gary Guo <gary@garyguo.net>
Cc: Boqun Feng <boqun@kernel.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Matthew Maurer <mmaurer@google.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust")
Acked-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

20 files changed, 353 insertions, 0 deletions

diff --git a/Documentation/gpu/xe/index.rst b/Documentation/gpu/xe/index.rst
new file mode 100644
index 000000000..665c0e936
--- /dev/null
+++ b/Documentation/gpu/xe/index.rst
@@ -0,0 +1,37 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+.. _drm/xe:
+
+=======================
+drm/xe Intel GFX Driver
+=======================
+
+The drm/xe driver supports some future GFX cards with rendering, display,
+compute and media. Support for currently available platforms like TGL, ADL,
+DG2, etc is provided to prototype the driver.
+
+The display, or :ref:`drm-kms`, support for drm/xe is provided by
+:ref:`drm/intel-display`, and shared with :ref:`drm/i915 <drm/i915>`.
+
+.. toctree::
+   :titlesonly:
+
+   xe_mm
+   xe_map
+   xe_migrate
+   xe_exec_queue
+   xe_cs
+   xe_pm
+   xe_gt_freq
+   xe_pcode
+   xe_gt_mcr
+   xe_wa
+   xe_rtp
+   xe_firmware
+   xe_tile
+   xe_debugging
+   xe_devcoredump
+   xe_device
+   xe-drm-usage-stats.rst
+   xe_configfs
+   xe_gt_stats
diff --git a/Documentation/gpu/xe/xe-drm-usage-stats.rst b/Documentation/gpu/xe/xe-drm-usage-stats.rst
new file mode 100644
index 000000000..482d503ae
--- /dev/null
+++ b/Documentation/gpu/xe/xe-drm-usage-stats.rst
@@ -0,0 +1,10 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+.. _xe-usage-stats:
+
+========================================
+Xe DRM client usage stats implementation
+========================================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_drm_client.c
+   :doc: DRM Client usage stats
diff --git a/Documentation/gpu/xe/xe_configfs.rst b/Documentation/gpu/xe/xe_configfs.rst
new file mode 100644
index 000000000..7f8ec39dc
--- /dev/null
+++ b/Documentation/gpu/xe/xe_configfs.rst
@@ -0,0 +1,16 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+.. _xe_configfs:
+
+===========
+Xe Configfs
+===========
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_configfs.c
+   :doc: Xe Configfs
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_configfs.c
+   :internal:
diff --git a/Documentation/gpu/xe/xe_cs.rst b/Documentation/gpu/xe/xe_cs.rst
new file mode 100644
index 000000000..e379aed4f
--- /dev/null
+++ b/Documentation/gpu/xe/xe_cs.rst
@@ -0,0 +1,8 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+==================
+Command submission
+==================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_exec.c
+   :doc: Execbuf (User GPU command submission)
diff --git a/Documentation/gpu/xe/xe_debugging.rst b/Documentation/gpu/xe/xe_debugging.rst
new file mode 100644
index 000000000..d65e56ff3
--- /dev/null
+++ b/Documentation/gpu/xe/xe_debugging.rst
@@ -0,0 +1,7 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+=========
+Debugging
+=========
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_assert.h
diff --git a/Documentation/gpu/xe/xe_devcoredump.rst b/Documentation/gpu/xe/xe_devcoredump.rst
new file mode 100644
index 000000000..ae4ec0e34
--- /dev/null
+++ b/Documentation/gpu/xe/xe_devcoredump.rst
@@ -0,0 +1,14 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+==================
+Xe Device Coredump
+==================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_devcoredump.c
+   :doc: Xe device coredump
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_devcoredump.c
+   :internal:
diff --git a/Documentation/gpu/xe/xe_device.rst b/Documentation/gpu/xe/xe_device.rst
new file mode 100644
index 000000000..39a937b97
--- /dev/null
+++ b/Documentation/gpu/xe/xe_device.rst
@@ -0,0 +1,10 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+.. _xe-device-wedging:
+
+==================
+Xe Device Wedging
+==================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_device.c
+   :doc: Xe Device Wedging
diff --git a/Documentation/gpu/xe/xe_exec_queue.rst b/Documentation/gpu/xe/xe_exec_queue.rst
new file mode 100644
index 000000000..870780621
--- /dev/null
+++ b/Documentation/gpu/xe/xe_exec_queue.rst
@@ -0,0 +1,34 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+===============
+Execution Queue
+===============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_exec_queue.c
+   :doc: Execution Queue
+
+Multi Queue Group
+=================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_exec_queue.c
+   :doc: Multi Queue Group
+
+.. _multi-queue-group-guc-interface:
+
+Multi Queue Group GuC interface
+===============================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_guc_submit.c
+   :doc: Multi Queue Group GuC interface
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_exec_queue_types.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_exec_queue.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_exec_queue.c
+   :internal:
diff --git a/Documentation/gpu/xe/xe_firmware.rst b/Documentation/gpu/xe/xe_firmware.rst
new file mode 100644
index 000000000..d3030d1c9
--- /dev/null
+++ b/Documentation/gpu/xe/xe_firmware.rst
@@ -0,0 +1,46 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+========
+Firmware
+========
+
+Firmware Layout
+===============
+
+.. kernel-doc:: drivers/gpu/drm/xe/abi/uc_fw_abi.h
+   :doc: CSS-based Firmware Layout
+
+.. kernel-doc:: drivers/gpu/drm/xe/abi/uc_fw_abi.h
+   :doc: GSC-based Firmware Layout
+
+Write Once Protected Content Memory (WOPCM) Layout
+==================================================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_wopcm.c
+   :doc: Write Once Protected Content Memory (WOPCM) Layout
+
+GuC CTB Blob
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_guc_ct.c
+   :doc: GuC CTB Blob
+
+GuC Power Conservation (PC)
+===========================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_guc_pc.c
+   :doc: GuC Power Conservation (PC)
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_guc_rc.c
+   :doc: GuC Render C-states (GuC RC)
+
+PCIe Gen5 Limitations
+=====================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_device_sysfs.c
+   :doc: PCIe Gen5 Limitations
+
+Internal API
+============
+
+TODO
diff --git a/Documentation/gpu/xe/xe_gt_freq.rst b/Documentation/gpu/xe/xe_gt_freq.rst
new file mode 100644
index 000000000..182d6aabe
--- /dev/null
+++ b/Documentation/gpu/xe/xe_gt_freq.rst
@@ -0,0 +1,17 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+==========================
+Xe GT Frequency Management
+==========================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_gt_freq.c
+   :doc: Xe GT Frequency Management
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_gt_throttle.c
+   :doc: Xe GT Throttle
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_gt_freq.c
+   :internal:
diff --git a/Documentation/gpu/xe/xe_gt_mcr.rst b/Documentation/gpu/xe/xe_gt_mcr.rst
new file mode 100644
index 000000000..848c07bc3
--- /dev/null
+++ b/Documentation/gpu/xe/xe_gt_mcr.rst
@@ -0,0 +1,13 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+==============================================
+GT Multicast/Replicated (MCR) Register Support
+==============================================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_gt_mcr.c
+   :doc: GT Multicast/Replicated (MCR) Register Support
+
+Internal API
+============
+
+TODO
diff --git a/Documentation/gpu/xe/xe_gt_stats.rst b/Documentation/gpu/xe/xe_gt_stats.rst
new file mode 100644
index 000000000..5ff806aba
--- /dev/null
+++ b/Documentation/gpu/xe/xe_gt_stats.rst
@@ -0,0 +1,11 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+================
+Xe GT Statistics
+================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_gt_stats.c
+   :doc: Xe GT Statistics
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_gt_stats_types.h
+   :internal:
diff --git a/Documentation/gpu/xe/xe_map.rst b/Documentation/gpu/xe/xe_map.rst
new file mode 100644
index 000000000..a098cfd2d
--- /dev/null
+++ b/Documentation/gpu/xe/xe_map.rst
@@ -0,0 +1,8 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+=========
+Map Layer
+=========
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_map.h
+   :doc: Map layer
diff --git a/Documentation/gpu/xe/xe_migrate.rst b/Documentation/gpu/xe/xe_migrate.rst
new file mode 100644
index 000000000..f92faec0a
--- /dev/null
+++ b/Documentation/gpu/xe/xe_migrate.rst
@@ -0,0 +1,8 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+=============
+Migrate Layer
+=============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_migrate_doc.h
+   :doc: Migrate Layer
diff --git a/Documentation/gpu/xe/xe_mm.rst b/Documentation/gpu/xe/xe_mm.rst
new file mode 100644
index 000000000..95864a450
--- /dev/null
+++ b/Documentation/gpu/xe/xe_mm.rst
@@ -0,0 +1,29 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+=================
+Memory Management
+=================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_bo_doc.h
+   :doc: Buffer Objects (BO)
+
+GGTT
+====
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_ggtt.c
+   :doc: Global Graphics Translation Table (GGTT)
+
+GGTT Internal API
+-----------------
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_ggtt_types.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_ggtt.c
+   :internal:
+
+Pagetable building
+==================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_pt.c
+   :doc: Pagetable building
diff --git a/Documentation/gpu/xe/xe_pcode.rst b/Documentation/gpu/xe/xe_pcode.rst
new file mode 100644
index 000000000..2a4360112
--- /dev/null
+++ b/Documentation/gpu/xe/xe_pcode.rst
@@ -0,0 +1,23 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+=====
+Pcode
+=====
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_pcode.c
+   :doc: PCODE
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_pcode.c
+   :internal:
+
+.. _xe-survivability-mode:
+
+==================
+Survivability Mode
+==================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_survivability_mode.c
+   :doc: Survivability Mode
diff --git a/Documentation/gpu/xe/xe_pm.rst b/Documentation/gpu/xe/xe_pm.rst
new file mode 100644
index 000000000..6781cdfb2
--- /dev/null
+++ b/Documentation/gpu/xe/xe_pm.rst
@@ -0,0 +1,14 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+========================
+Runtime Power Management
+========================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_pm.c
+   :doc: Xe Power Management
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_pm.c
+   :internal:
diff --git a/Documentation/gpu/xe/xe_rtp.rst b/Documentation/gpu/xe/xe_rtp.rst
new file mode 100644
index 000000000..7fdf4b6c1
--- /dev/null
+++ b/Documentation/gpu/xe/xe_rtp.rst
@@ -0,0 +1,20 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+=========================
+Register Table Processing
+=========================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_rtp.c
+   :doc: Register Table Processing
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_rtp_types.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_rtp.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_rtp.c
+   :internal:
diff --git a/Documentation/gpu/xe/xe_tile.rst b/Documentation/gpu/xe/xe_tile.rst
new file mode 100644
index 000000000..c33f68dd9
--- /dev/null
+++ b/Documentation/gpu/xe/xe_tile.rst
@@ -0,0 +1,14 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+==================
+Multi-tile Devices
+==================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_tile.c
+   :doc: Multi-tile Design
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_tile.c
+   :internal:
diff --git a/Documentation/gpu/xe/xe_wa.rst b/Documentation/gpu/xe/xe_wa.rst
new file mode 100644
index 000000000..f8811cc6a
--- /dev/null
+++ b/Documentation/gpu/xe/xe_wa.rst
@@ -0,0 +1,14 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+====================
+Hardware workarounds
+====================
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_wa.c
+   :doc: Hardware workarounds
+
+Internal API
+============
+
+.. kernel-doc:: drivers/gpu/drm/xe/xe_wa.c
+   :internal: