livepatch: Remove klp_check_compiler_support()

The only purpose of klp_check_compiler_support() is to make sure that we
are not using ftrace on x86 via mcount (because that's executed only after
prologue has already happened, and that's too late for livepatching
purposes).

Now that mcount is not supported by ftrace any more, there is no need for
klp_check_compiler_support() either.

Link: http://lkml.kernel.org/r/nycvar.YFH.7.76.1905102346100.17054@cbobk.fhfr.pm

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

1 files changed, 0 insertions, 8 deletions

diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index eb0ee10a1981..112a36ed4a09 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -1220,14 +1220,6 @@ void klp_module_going(struct module *mod)
 
 static int __init klp_init(void)
 {
-        int ret;
-
-        ret = klp_check_compiler_support();
-        if (ret) {
-                pr_info("Your compiler is too old; turning off.\n");
-                return -EINVAL;
-        }
-
         klp_root_kobj = kobject_create_and_add("livepatch", kernel_kobj);
         if (!klp_root_kobj)
                 return -ENOMEM;