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| 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 /drivers/net/arcnet/com9026.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 'drivers/net/arcnet/com9026.h')
| -rw-r--r-- | drivers/net/arcnet/com9026.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/net/arcnet/com9026.h b/drivers/net/arcnet/com9026.h new file mode 100644 index 000000000..6adbc1871 --- /dev/null +++ b/drivers/net/arcnet/com9026.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __COM9026_H +#define __COM9026_H + +/* COM 9026 controller chip --> ARCnet register addresses */ + +#define COM9026_REG_W_INTMASK 0 /* writable */ +#define COM9026_REG_R_STATUS 0 /* readable */ +#define COM9026_REG_W_COMMAND 1 /* writable, returns random vals on read (?) */ +#define COM9026_REG_RW_CONFIG 2 /* Configuration register */ +#define COM9026_REG_R_RESET 8 /* software reset (on read) */ +#define COM9026_REG_RW_MEMDATA 12 /* Data port for IO-mapped memory */ +#define COM9026_REG_W_ADDR_LO 14 /* Control registers for said */ +#define COM9026_REG_W_ADDR_HI 15 + +#define COM9026_REG_R_STATION 1 /* Station ID */ + +#endif |