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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/rtc/rtc-s3c.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/rtc/rtc-s3c.h')
| -rw-r--r-- | drivers/rtc/rtc-s3c.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-s3c.h b/drivers/rtc/rtc-s3c.h new file mode 100644 index 000000000..11d7a1255 --- /dev/null +++ b/drivers/rtc/rtc-s3c.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2003 Simtec Electronics <linux@simtec.co.uk> + * http://www.simtec.co.uk/products/SWLINUX/ + * + * S3C2410 Internal RTC register definition +*/ + +#ifndef __ASM_ARCH_REGS_RTC_H +#define __ASM_ARCH_REGS_RTC_H __FILE__ + +#define S3C2410_RTCREG(x) (x) +#define S3C2410_INTP S3C2410_RTCREG(0x30) +#define S3C2410_INTP_ALM (1 << 1) +#define S3C2410_INTP_TIC (1 << 0) + +#define S3C2410_RTCCON S3C2410_RTCREG(0x40) +#define S3C2410_RTCCON_RTCEN (1 << 0) +#define S3C2410_RTCCON_CNTSEL (1 << 2) +#define S3C2410_RTCCON_CLKRST (1 << 3) +#define S3C2443_RTCCON_TICSEL (1 << 4) +#define S3C64XX_RTCCON_TICEN (1 << 8) + +#define S3C2410_RTCALM S3C2410_RTCREG(0x50) +#define S3C2410_RTCALM_ALMEN (1 << 6) +#define S3C2410_RTCALM_YEAREN (1 << 5) +#define S3C2410_RTCALM_MONEN (1 << 4) +#define S3C2410_RTCALM_DAYEN (1 << 3) +#define S3C2410_RTCALM_HOUREN (1 << 2) +#define S3C2410_RTCALM_MINEN (1 << 1) +#define S3C2410_RTCALM_SECEN (1 << 0) + +#define S3C2410_ALMSEC S3C2410_RTCREG(0x54) +#define S3C2410_ALMMIN S3C2410_RTCREG(0x58) +#define S3C2410_ALMHOUR S3C2410_RTCREG(0x5c) + +#define S3C2410_ALMDATE S3C2410_RTCREG(0x60) +#define S3C2410_ALMMON S3C2410_RTCREG(0x64) +#define S3C2410_ALMYEAR S3C2410_RTCREG(0x68) + +#define S3C2410_RTCSEC S3C2410_RTCREG(0x70) +#define S3C2410_RTCMIN S3C2410_RTCREG(0x74) +#define S3C2410_RTCHOUR S3C2410_RTCREG(0x78) +#define S3C2410_RTCDATE S3C2410_RTCREG(0x7c) +#define S3C2410_RTCMON S3C2410_RTCREG(0x84) +#define S3C2410_RTCYEAR S3C2410_RTCREG(0x88) + +#endif /* __ASM_ARCH_REGS_RTC_H */ |