From af026796054fb70439e919a925615e61b500ef6b Mon Sep 17 00:00:00 2001 From: Joe Lawrence Date: Fri, 13 Oct 2017 15:08:43 -0400 Subject: [PATCH] livepatch: add transition notices Log a few kernel debug messages at the beginning of the following livepatch transition functions: klp_complete_transition() klp_cancel_transition() klp_init_transition() klp_reverse_transition() Also update the log notice message in klp_start_transition() for similar verbiage as the above messages. Suggested-by: Josh Poimboeuf Signed-off-by: Joe Lawrence Acked-by: Miroslav Benes Acked-by: Josh Poimboeuf Signed-off-by: Jiri Kosina --- kernel/livepatch/transition.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c index 53887f0bca10..56add6327736 100644 --- a/kernel/livepatch/transition.c +++ b/kernel/livepatch/transition.c @@ -82,6 +82,10 @@ static void klp_complete_transition(void) unsigned int cpu; bool immediate_func = false; + pr_debug("'%s': completing %s transition\n", + klp_transition_patch->mod->name, + klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); + if (klp_target_state == KLP_UNPATCHED) { /* * All tasks have transitioned to KLP_UNPATCHED so we can now @@ -163,6 +167,9 @@ void klp_cancel_transition(void) if (WARN_ON_ONCE(klp_target_state != KLP_PATCHED)) return; + pr_debug("'%s': canceling patching transition, going to unpatch\n", + klp_transition_patch->mod->name); + klp_target_state = KLP_UNPATCHED; klp_complete_transition(); } @@ -441,7 +448,8 @@ void klp_start_transition(void) WARN_ON_ONCE(klp_target_state == KLP_UNDEFINED); - pr_notice("'%s': %s...\n", klp_transition_patch->mod->name, + pr_notice("'%s': starting %s transition\n", + klp_transition_patch->mod->name, klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); /* @@ -497,6 +505,9 @@ void klp_init_transition(struct klp_patch *patch, int state) */ klp_target_state = state; + pr_debug("'%s': initializing %s transition\n", patch->mod->name, + klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); + /* * If the patch can be applied or reverted immediately, skip the * per-task transitions. @@ -562,6 +573,11 @@ void klp_reverse_transition(void) unsigned int cpu; struct task_struct *g, *task; + pr_debug("'%s': reversing transition from %s\n", + klp_transition_patch->mod->name, + klp_target_state == KLP_PATCHED ? "patching to unpatching" : + "unpatching to patching"); + klp_transition_patch->enabled = !klp_transition_patch->enabled; klp_target_state = !klp_target_state;