arm64: ftrace: fix ftrace_modify_graph_caller for branch replace
ftrace_enable_ftrace_graph_caller and ftrace_disable_ftrace_graph_caller
should replace B(jmp) instruction and not BL(call) instruction.
Commit 9f1ae7596aad("arm64: Correct ftrace calls to
aarch64_insn_gen_branch_imm()") had a typo and used
AARCH64_INSN_BRANCH_LINK instead of AARCH64_INSN_BRANCH_NOLINK.
Either instruction will work, as the link register is saved/restored
across the branch but this better matches the intention of the code.
Signed-off-by: Pratyush Anand <panand@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
index cf8556a..c851be7 100644
--- a/arch/arm64/kernel/ftrace.c
+++ b/arch/arm64/kernel/ftrace.c
@@ -156,7 +156,7 @@
branch = aarch64_insn_gen_branch_imm(pc,
(unsigned long)ftrace_graph_caller,
- AARCH64_INSN_BRANCH_LINK);
+ AARCH64_INSN_BRANCH_NOLINK);
nop = aarch64_insn_gen_nop();
if (enable)