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Subject[PATCH v6 16/18] arm64: ftrace: use function_nocfi for ftrace_call
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With CONFIG_CFI_CLANG, the compiler replaces function pointers with
jump table addresses, which breaks dynamic ftrace as the address of
ftrace_call is replaced with the address of ftrace_call.cfi_jt. Use
function_nocfi() to get the address of the actual function instead.

Suggested-by: Ben Dai <ben.dai@unisoc.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
---
arch/arm64/kernel/ftrace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
index 86a5cf9bc19a..b5d3ddaf69d9 100644
--- a/arch/arm64/kernel/ftrace.c
+++ b/arch/arm64/kernel/ftrace.c
@@ -55,7 +55,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
unsigned long pc;
u32 new;

- pc = (unsigned long)&ftrace_call;
+ pc = (unsigned long)function_nocfi(ftrace_call);
new = aarch64_insn_gen_branch_imm(pc, (unsigned long)func,
AARCH64_INSN_BRANCH_LINK);

--
2.31.1.295.g9ea45b61b8-goog
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