livepatch: Remove reliable stacktrace check in klp_try_switch_task()

Support for immediate flag was removed by commit d0807da78e11
("livepatch: Remove immediate feature").  We bail out during
patch registration for architectures, those don't support
reliable stack trace. Remove the check in klp_try_switch_task(),
as its not required.

Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c
index 7c6631e693bc6969983f2e3c0b3ecf84d68f7a79..5bc349805e033fbfdbf5fb811026044695289d0b 100644 (file)
--- a/kernel/livepatch/transition.c
+++ b/kernel/livepatch/transition.c
@@ -309,13 +309,6 @@ static bool klp_try_switch_task(struct task_struct *task)
        if (task->patch_state == klp_target_state)
                return true;
 
-       /*
-        * For arches which don't have reliable stack traces, we have to rely
-        * on other methods (e.g., switching tasks at kernel exit).
-        */
-       if (!klp_have_reliable_stack())
-               return false;
-
        /*
         * Now try to check the stack for any to-be-patched or to-be-unpatched
         * functions.  If all goes well, switch the task to the target patch