ftrace/x86: Get the current mcount addr for add_breakpoint() (94792ea0) · Commits · 戴 / test

The add_breakpoint() code in the ftrace updating gets the address of what the call will become, but if the mcount address is changing from regs to non-regs ftrace_caller or vice versa, it will use what the record currently is. This is rather silly as the code should always use what is currently there regardless of if it's changing the regs function or just converting to a nop. Signed-off-by:

Steven Rostedt <rostedt@goodmis.org>

arch/x86/kernel/ftrace.c

+2 −4

Original line number	Diff line number	Diff line
		@@ -380,9 +380,9 @@ static int add_breakpoints(struct dyn_ftrace *rec, int enable)
		unsigned long ftrace_addr;
		int ret;

		ret = ftrace_test_record(rec, enable);
		ftrace_addr = get_ftrace_old_addr(rec);

		ftrace_addr = get_ftrace_addr(rec);
		ret = ftrace_test_record(rec, enable);

		switch (ret) {
		case FTRACE_UPDATE_IGNORE:
		@@ -394,8 +394,6 @@ static int add_breakpoints(struct dyn_ftrace *rec, int enable)

		case FTRACE_UPDATE_MODIFY_CALL_REGS:
		case FTRACE_UPDATE_MODIFY_CALL:
		ftrace_addr = get_ftrace_old_addr(rec);
		/* fall through */
		case FTRACE_UPDATE_MAKE_NOP:
		/* converting a call to a nop */
		return add_brk_on_call(rec, ftrace_addr);

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