]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
riscv: ftrace: Add parentheses in macro definitions of make_call_t0 and make_call_ra
authorJuhan Jin <juhan.jin@foxmail.com>
Thu, 6 Feb 2025 19:28:36 +0000 (13:28 -0600)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 10 Apr 2025 12:39:32 +0000 (14:39 +0200)
commit4119e80ce22df78b18f291c0e9891edace607b2f
tree2db3905f6def29940eb6fb9c2c0152226d57a4af
parent8522051c58d68146b93e8a5ba9987e83b3d64e7b
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>
arch/riscv/include/asm/ftrace.h