diff options
| author | Miguel Ojeda <ojeda@kernel.org> | 2026-08-16 15:32:33 +0200 |
|---|---|---|
| committer | Miguel Ojeda <ojeda@kernel.org> | 2026-08-23 21:27:17 +0200 |
| commit | 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 (patch) | |
| tree | 93a1ed1d337bc53adf1e572c2586d347703b286e /include/video/pmag-ba-fb.h | |
| download | linux-stable-5febf432df1cfa5b25d99b54c32103fafbdd0eb9.tar.gz linux-stable-5febf432df1cfa5b25d99b54c32103fafbdd0eb9.zip | |
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>
Diffstat (limited to 'include/video/pmag-ba-fb.h')
| -rw-r--r-- | include/video/pmag-ba-fb.h | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/include/video/pmag-ba-fb.h b/include/video/pmag-ba-fb.h new file mode 100644 index 000000000..fceb6c0f6 --- /dev/null +++ b/include/video/pmag-ba-fb.h @@ -0,0 +1,27 @@ +/* + * linux/include/video/pmag-ba-fb.h + * + * TURBOchannel PMAG-BA Color Frame Buffer (CFB) card support, + * Copyright (C) 1999, 2000, 2001 by + * Michael Engel <engel@unix-ag.org>, + * Karsten Merker <merker@linuxtag.org> + * Copyright (c) 2005 Maciej W. Rozycki + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of this + * archive for more details. + */ + +/* IOmem resource offsets. */ +#define PMAG_BA_FBMEM 0x000000 /* frame buffer */ +#define PMAG_BA_BT459 0x200000 /* Bt459 RAMDAC */ +#define PMAG_BA_IRQ 0x300000 /* IRQ acknowledge */ +#define PMAG_BA_ROM 0x380000 /* REX option ROM */ +#define PMAG_BA_BT438 0x380000 /* Bt438 clock chip reset */ +#define PMAG_BA_SIZE 0x400000 /* address space size */ + +/* Bt459 register offsets, byte-wide registers. */ +#define BT459_ADDR_LO 0x0 /* address low */ +#define BT459_ADDR_HI 0x4 /* address high */ +#define BT459_DATA 0x8 /* data window register */ +#define BT459_CMAP 0xc /* color map window register */ |