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riscv: ftrace: Add parentheses in macro definitions of make_call_t0 and make_call_ra

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[ 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>
This commit is contained in:
Juhan Jin 2025-02-06 13:28:36 -06:00 committed by Greg Kroah-Hartman
parent a333f223e5
commit fb5069d017
1 changed files with 2 additions and 2 deletions
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4
arch/riscv/include/asm/ftrace.h
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@ -82,7 +82,7 @@ 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)
@ -98,7 +98,7 @@ 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)