Re: [PATCH] ftrace/x86: Add a comment to why we take text_mutex in ftrace_arch_code_modify_prepare()

[Petr Mladek]

On Thu 2019-06-27 21:18:19, Steven Rostedt wrote:
> 
> From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
> 
> Taking the text_mutex in ftrace_arch_code_modify_prepare() is to fix a
> race against module loading and live kernel patching that might try to
> change the text permissions while ftrace has it as read/write. This
> really needs to be documented in the code. Add a comment that does such.
> 
> Suggested-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>

Best Regards,
Petr