From fb5069d017b5bc63940b0916d985bd4df0d12eb1 Mon Sep 17 00:00:00 2001 From: Juhan Jin Date: Thu, 6 Feb 2025 13:28:36 -0600 Subject: [PATCH] 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 Reviewed-by: Alexandre Ghiti Link: https://lore.kernel.org/r/tencent_AE90AA59903A628E87E9F80E563DA5BA5508@qq.com Signed-off-by: Alexandre Ghiti Signed-off-by: Sasha Levin --- arch/riscv/include/asm/ftrace.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index dcf1bc9de584..3d97c951a384 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -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)