diff options
| author | Juhan Jin <juhan.jin@foxmail.com> | 2025-02-06 13:28:36 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-04-10 14:39:32 +0200 |
| commit | 4119e80ce22df78b18f291c0e9891edace607b2f (patch) | |
| tree | 2db3905f6def29940eb6fb9c2c0152226d57a4af | |
| parent | 8522051c58d68146b93e8a5ba9987e83b3d64e7b (diff) | |
riscv: ftrace: Add parentheses in macro definitions of make_call_t0 and make_call_ra
[ Upstream commit 5f1a58ed91a040d4625d854f9bb3dd4995919202 ]
This patch adds parentheses to parameters caller and callee of macros
make_call_t0 and make_call_ra. Every existing invocation of these two
macros uses a single variable for each argument, so the absence of the
parentheses seems okay. However, future invocations might use more
complex expressions as arguments. For example, a future invocation might
look like this: make_call_t0(a - b, c, call). Without parentheses in the
macro definition, the macro invocation expands to:
...
unsigned int offset = (unsigned long) c - (unsigned long) a - b;
...
which is clearly wrong.
The use of parentheses ensures arguments are correctly evaluated and
potentially saves future users of make_call_t0 and make_call_ra debugging
trouble.
Fixes: 6724a76cff85 ("riscv: ftrace: Reduce the detour code size to half")
Signed-off-by: Juhan Jin <juhan.jin@foxmail.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/tencent_AE90AA59903A628E87E9F80E563DA5BA5508@qq.com
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | arch/riscv/include/asm/ftrace.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index 2cddd79ff21b..f253c8dae878 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -92,7 +92,7 @@ struct dyn_arch_ftrace { #define make_call_t0(caller, callee, call) \ do { \ unsigned int offset = \ - (unsigned long) callee - (unsigned long) caller; \ + (unsigned long) (callee) - (unsigned long) (caller); \ call[0] = to_auipc_t0(offset); \ call[1] = to_jalr_t0(offset); \ } while (0) @@ -108,7 +108,7 @@ do { \ #define make_call_ra(caller, callee, call) \ do { \ unsigned int offset = \ - (unsigned long) callee - (unsigned long) caller; \ + (unsigned long) (callee) - (unsigned long) (caller); \ call[0] = to_auipc_ra(offset); \ call[1] = to_jalr_ra(offset); \ } while (0) |