tree d1fdc5c65a3006941edc142b86935d6cffe55ce8
parent a53276e2826010338478ed94310874001a8097fa
author Thomas Gleixner <tglx@linutronix.de> 1495702671 +0200
committer Steven Rostedt (VMware) <rostedt@goodmis.org> 1495852622 -0400

x86/ftrace: Make sure that ftrace trampolines are not RWX

ftrace use module_alloc() to allocate trampoline pages. The mapping of
module_alloc() is RWX, which makes sense as the memory is written to right
after allocation. But nothing makes these pages RO after writing to them.

Add proper set_memory_rw/ro() calls to protect the trampolines after
modification.

Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1705251056410.1862@nanos

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>