3  * transition.c - Kernel Live Patching transition functions
15 #include "transition.h"
51  * "straggler" tasks which failed to transition in the first attempt.
87  * The transition to the target patch state is complete.  Clean up the data
97 	pr_debug("'%s': completing %s transition\n",  in klp_complete_transition()
116 		 * func->transition gets cleared, the handler may choose a  in klp_complete_transition()
124 			func->transition = false;  in klp_complete_transition()
160  * This is called in the error path, to cancel a transition before it has
162  * klp_start_transition() hasn't.  If the transition *has* been started,
170 	pr_debug("'%s': canceling patching transition, going to unpatch\n",  in klp_cancel_transition()
201 	 *    of func->transition, if klp_ftrace_handler() is called later on  in klp_update_patch_state()
260  * Determine whether it's safe to transition the task to the target patch state
466 	 * Usually this will transition most (or all) of the tasks on a system  in klp_try_complete_transition()
527  * Start the transition to the specified target patch state so tasks can begin
537 	pr_notice("'%s': starting %s transition\n",  in klp_start_transition()
570  * state, and initialize all function transition states to true in preparation
591 	pr_debug("'%s': initializing %s transition\n", patch->mod->name,  in klp_init_transition()
616 	 * func->transition updates to ensure that klp_ftrace_handler() doesn't  in klp_init_transition()
617 	 * see a func in transition with a task->patch_state of KLP_TRANSITION_IDLE.  in klp_init_transition()
627 	 * Set the func transition states so klp_ftrace_handler() will know to  in klp_init_transition()
628 	 * switch to the transition logic.  in klp_init_transition()
639 			func->transition = true;  in klp_init_transition()
643  * This function can be called in the middle of an existing transition to
653 	pr_debug("'%s': reversing transition from %s\n",  in klp_reverse_transition()
661 	 * parallel with the reverse transition.  in klp_reverse_transition()
674 	 * starting the reverse transition.  in klp_reverse_transition()
680 	 * prepare for the reverse transition.  in klp_reverse_transition()
701 	 * The parent process may have gone through a KLP transition since  in klp_copy_process()
720  * existing transition to finish.