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>

1 files changed, 99 insertions, 0 deletions

diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv
new file mode 100644
index 000000000..bfbfbf4f1
--- /dev/null
+++ b/Documentation/gpu/kms-properties.csv
@@ -0,0 +1,99 @@
+Owner Module/Drivers,Group,Property Name,Type,Property Values,Object attached,Description/Restrictions
+,DVI-I,“subconnector”,ENUM,"{ “Unknown”, “DVI-D”, “DVI-A” }",Connector,TBD
+,,“select subconnector”,ENUM,"{ “Automatic”, “DVI-D”, “DVI-A” }",Connector,TBD
+,TV,“subconnector”,ENUM,"{ ""Unknown"", ""Composite"", ""SVIDEO"", ""Component"", ""SCART"" }",Connector,TBD
+,,“select subconnector”,ENUM,"{ ""Automatic"", ""Composite"", ""SVIDEO"", ""Component"", ""SCART"" }",Connector,TBD
+,,“mode”,ENUM,"{ ""NTSC_M"", ""NTSC_J"", ""NTSC_443"", ""PAL_B"" } etc.",Connector,TBD
+,,“left margin”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“right margin”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“top margin”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“bottom margin”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“brightness”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“contrast”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“flicker reduction”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“overscan”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“saturation”,RANGE,"Min=0, Max=100",Connector,TBD
+,,“hue”,RANGE,"Min=0, Max=100",Connector,TBD
+,Virtual GPU,“suggested X”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an X offset for a connector
+,,“suggested Y”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an Y offset for a connector
+,Optional,"""aspect ratio""",ENUM,"{ ""None"", ""4:3"", ""16:9"" }",Connector,TDB
+,,“audio”,ENUM,"{ ""force-dvi"", ""off"", ""auto"", ""on"" }",Connector,TBD
+,SDVO-TV,“mode”,ENUM,"{ ""NTSC_M"", ""NTSC_J"", ""NTSC_443"", ""PAL_B"" } etc.",Connector,TBD
+,,"""left_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,"""right_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,"""top_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,"""bottom_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“hpos”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“vpos”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“contrast”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“saturation”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“hue”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“sharpness”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“flicker_filter”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“flicker_filter_adaptive”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“flicker_filter_2d”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“tv_chroma_filter”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“tv_luma_filter”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“dot_crawl”,RANGE,"Min=0, Max=1",Connector,TBD
+,SDVO-TV/LVDS,“brightness”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+CDV gma-500,Generic,"""Broadcast RGB""",ENUM,"{ “Full”, “Limited 16:235” }",Connector,TBD
+Poulsbo,Generic,“backlight”,RANGE,"Min=0, Max=100",Connector,TBD
+,SDVO-TV,“mode”,ENUM,"{ ""NTSC_M"", ""NTSC_J"", ""NTSC_443"", ""PAL_B"" } etc.",Connector,TBD
+,,"""left_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,"""right_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,"""top_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,"""bottom_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“hpos”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“vpos”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“contrast”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“saturation”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“hue”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“sharpness”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“flicker_filter”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“flicker_filter_adaptive”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“flicker_filter_2d”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“tv_chroma_filter”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“tv_luma_filter”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+,,“dot_crawl”,RANGE,"Min=0, Max=1",Connector,TBD
+,SDVO-TV/LVDS,“brightness”,RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
+armada,CRTC,"""CSC_YUV""",ENUM,"{ ""Auto"" , ""CCIR601"", ""CCIR709"" }",CRTC,TBD
+,,"""CSC_RGB""",ENUM,"{ ""Auto"", ""Computer system"", ""Studio"" }",CRTC,TBD
+,Overlay,"""colorkey""",RANGE,"Min=0, Max=0xffffff",Plane,TBD
+,,"""colorkey_min""",RANGE,"Min=0, Max=0xffffff",Plane,TBD
+,,"""colorkey_max""",RANGE,"Min=0, Max=0xffffff",Plane,TBD
+,,"""colorkey_val""",RANGE,"Min=0, Max=0xffffff",Plane,TBD
+,,"""colorkey_alpha""",RANGE,"Min=0, Max=0xffffff",Plane,TBD
+,,"""colorkey_mode""",ENUM,"{ ""disabled"", ""Y component"", ""U component"" , ""V component"", ""RGB"", “R component"", ""G component"", ""B component"" }",Plane,TBD
+,,"""brightness""",RANGE,"Min=0, Max=256 + 255",Plane,TBD
+,,"""contrast""",RANGE,"Min=0, Max=0x7fff",Plane,TBD
+,,"""saturation""",RANGE,"Min=0, Max=0x7fff",Plane,TBD
+exynos,CRTC,“mode”,ENUM,"{ ""normal"", ""blank"" }",CRTC,TBD
+i2c/ch7006_drv,Generic,“scale”,RANGE,"Min=0, Max=2",Connector,TBD
+,TV,“mode”,ENUM,"{ ""PAL"", ""PAL-M"",""PAL-N""}, ”PAL-Nc"" , ""PAL-60"", ""NTSC-M"", ""NTSC-J"" }",Connector,TBD
+nouveau,NV10 Overlay,"""colorkey""",RANGE,"Min=0, Max=0x01ffffff",Plane,TBD
+,,“contrast”,RANGE,"Min=0, Max=8192-1",Plane,TBD
+,,“brightness”,RANGE,"Min=0, Max=1024",Plane,TBD
+,,“hue”,RANGE,"Min=0, Max=359",Plane,TBD
+,,“saturation”,RANGE,"Min=0, Max=8192-1",Plane,TBD
+,,“iturbt_709”,RANGE,"Min=0, Max=1",Plane,TBD
+,Nv04 Overlay,“colorkey”,RANGE,"Min=0, Max=0x01ffffff",Plane,TBD
+,,“brightness”,RANGE,"Min=0, Max=1024",Plane,TBD
+,Display,“dithering mode”,ENUM,"{ ""auto"", ""off"", ""on"" }",Connector,TBD
+,,“dithering depth”,ENUM,"{ ""auto"", ""off"", ""on"", ""static 2x2"", ""dynamic 2x2"", ""temporal"" }",Connector,TBD
+,,“underscan”,ENUM,"{ ""auto"", ""6 bpc"", ""8 bpc"" }",Connector,TBD
+,,“underscan hborder”,RANGE,"Min=0, Max=128",Connector,TBD
+,,“underscan vborder”,RANGE,"Min=0, Max=128",Connector,TBD
+,,“vibrant hue”,RANGE,"Min=0, Max=180",Connector,TBD
+,,“color vibrance”,RANGE,"Min=0, Max=200",Connector,TBD
+omap,Generic,“zorder”,RANGE,"Min=0, Max=3","CRTC, Plane",TBD
+qxl,Generic,"“hotplug_mode_update""",RANGE,"Min=0, Max=1",Connector,TBD
+radeon,DVI-I,“coherent”,RANGE,"Min=0, Max=1",Connector,TBD
+,DAC enable load detect,“load detection”,RANGE,"Min=0, Max=1",Connector,TBD
+,TV Standard,"""tv standard""",ENUM,"{ ""ntsc"", ""pal"", ""pal-m"", ""pal-60"", ""ntsc-j"" , ""scart-pal"", ""pal-cn"", ""secam"" }",Connector,TBD
+,legacy TMDS PLL detect,"""tmds_pll""",ENUM,"{ ""driver"", ""bios"" }",-,TBD
+,Underscan,"""underscan""",ENUM,"{ ""off"", ""on"", ""auto"" }",Connector,TBD
+,,"""underscan hborder""",RANGE,"Min=0, Max=128",Connector,TBD
+,,"""underscan vborder""",RANGE,"Min=0, Max=128",Connector,TBD
+,Audio,“audio”,ENUM,"{ ""off"", ""on"", ""auto"" }",Connector,TBD
+,FMT Dithering,“dither”,ENUM,"{ ""off"", ""on"" }",Connector,TBD
+,,"""colorkey""",RANGE,"Min=0, Max=0x01ffffff",Plane,TBD