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| author | Juhan Jin <juhan.jin@foxmail.com> | 2025-02-06 13:28:36 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-04-10 14:37:38 +0200 |
| commit | 2174fa133dcca91150dddb0bde2f4fee30019f88 (patch) | |
| tree | 60cbbaee36af6f0db491165887789818d7ca0183 /arch/riscv | |
| parent | 239ea3c34673b3244a499fd65771c47e5bffcbb0 (diff) | |
| download | linux-2174fa133dcca91150dddb0bde2f4fee30019f88.tar.gz linux-2174fa133dcca91150dddb0bde2f4fee30019f88.tar.bz2 linux-2174fa133dcca91150dddb0bde2f4fee30019f88.zip | |
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>
Diffstat (limited to 'arch/riscv')
| -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 42777f91a9c5..9004dfec8c85 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -103,7 +103,7 @@ 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) @@ -119,7 +119,7 @@ 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) |