diff options
| author | Andy Chiu <andy.chiu@sifive.com> | 2025-04-08 02:08:25 +0800 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@dabbelt.com> | 2025-06-05 11:09:21 -0700 |
| commit | f8693f6dffcd1865da7f5f4c3df1de445e519bec (patch) | |
| tree | 3c8c111d2a2866e27fd449144e4e190bbe28cd0c | |
| parent | 9c32cda43eb78f78c73aee4aa344b777714e259b (diff) | |
riscv: ftrace: support fastcc in Clang for WITH_ARGS
Some caller-saved registers which are not defined as function arguments
in the ABI can still be passed as arguments when the kernel is compiled
with Clang. As a result, we must save and restore those registers to
prevent ftrace from clobbering them.
- [1]: https://reviews.llvm.org/D68559
Reported-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Closes: https://lore.kernel.org/linux-riscv/7e7c7914-445d-426d-89a0-59a9199c45b1@yadro.com/
Fixes: 7caa9765465f ("ftrace: riscv: move from REGS to ARGS")
Acked-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20250407180838.42877-1-andybnac@gmail.com
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
| -rw-r--r-- | arch/riscv/include/asm/ftrace.h | 7 | ||||
| -rw-r--r-- | arch/riscv/kernel/asm-offsets.c | 7 | ||||
| -rw-r--r-- | arch/riscv/kernel/mcount-dyn.S | 16 |
3 files changed, 28 insertions, 2 deletions
diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index d627f63ee289..d8b2138bd9c6 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -146,6 +146,13 @@ struct __arch_ftrace_regs { unsigned long a5; unsigned long a6; unsigned long a7; +#ifdef CONFIG_CC_IS_CLANG + unsigned long t2; + unsigned long t3; + unsigned long t4; + unsigned long t5; + unsigned long t6; +#endif }; }; }; diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c index 16490755304e..7c43c8e26ae7 100644 --- a/arch/riscv/kernel/asm-offsets.c +++ b/arch/riscv/kernel/asm-offsets.c @@ -501,6 +501,13 @@ void asm_offsets(void) DEFINE(FREGS_SP, offsetof(struct __arch_ftrace_regs, sp)); DEFINE(FREGS_S0, offsetof(struct __arch_ftrace_regs, s0)); DEFINE(FREGS_T1, offsetof(struct __arch_ftrace_regs, t1)); +#ifdef CONFIG_CC_IS_CLANG + DEFINE(FREGS_T2, offsetof(struct __arch_ftrace_regs, t2)); + DEFINE(FREGS_T3, offsetof(struct __arch_ftrace_regs, t3)); + DEFINE(FREGS_T4, offsetof(struct __arch_ftrace_regs, t4)); + DEFINE(FREGS_T5, offsetof(struct __arch_ftrace_regs, t5)); + DEFINE(FREGS_T6, offsetof(struct __arch_ftrace_regs, t6)); +#endif DEFINE(FREGS_A0, offsetof(struct __arch_ftrace_regs, a0)); DEFINE(FREGS_A1, offsetof(struct __arch_ftrace_regs, a1)); DEFINE(FREGS_A2, offsetof(struct __arch_ftrace_regs, a2)); diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S index 745dd4c4a69c..e988bd26b28b 100644 --- a/arch/riscv/kernel/mcount-dyn.S +++ b/arch/riscv/kernel/mcount-dyn.S @@ -96,7 +96,13 @@ REG_S x8, FREGS_S0(sp) #endif REG_S x6, FREGS_T1(sp) - +#ifdef CONFIG_CC_IS_CLANG + REG_S x7, FREGS_T2(sp) + REG_S x28, FREGS_T3(sp) + REG_S x29, FREGS_T4(sp) + REG_S x30, FREGS_T5(sp) + REG_S x31, FREGS_T6(sp) +#endif // save the arguments REG_S x10, FREGS_A0(sp) REG_S x11, FREGS_A1(sp) @@ -115,7 +121,13 @@ REG_L x8, FREGS_S0(sp) #endif REG_L x6, FREGS_T1(sp) - +#ifdef CONFIG_CC_IS_CLANG + REG_L x7, FREGS_T2(sp) + REG_L x28, FREGS_T3(sp) + REG_L x29, FREGS_T4(sp) + REG_L x30, FREGS_T5(sp) + REG_L x31, FREGS_T6(sp) +#endif // restore the arguments REG_L x10, FREGS_A0(sp) REG_L x11, FREGS_A1(sp) |