Merge tag 'liveupdate-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux

Pull liveupdate updates from Mike Rapoport:
 "Kexec Handover:

   - Fix size calculation in kho_preserved_memory_reserve() for
     preservations larger than 2 GiB

  Live Update Orchestrator:

   - move liveupdate selftest utilities into a library so that selftests
     of subsystems participating in liveupdate, e.g. PCI and VFIO, can
     use them and drop direct ioctl calls from the tests

   - add end to end liveupdate test infrastructure that allows running
     the tests across a kexec in QEMU

   - remove redundant INIT_LIST_HEAD in luo_session_alloc()

   - remember the error status of an FLB retrieve() and return it on
     subsequent attempts rather than retrying retrieve() with an FLB in
     an unexpected state

   - reference count the outgoing FLB so that it cannot be freed while a
     caller is using it, the same way it's done for the incoming FLB

   - reject nonzero reserved field in LIVEUPDATE_SESSION_FINISH so that
     it can be reused by a future extension"

* tag 'liveupdate-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux:
  kho: fix size calculation in kho_preserved_memory_reserve()
  selftests/liveupdate: Move luo_test_utils.* into a reusable library
  selftests/liveupdate: Use luo_test_utils.c for liveupdate ioctl APIs
  liveupdate: Remember FLB retrieve() status
  liveupdate: Reference count outgoing FLB data
  liveupdate: reject nonzero reserved value for SESSION_FINISH
  liveupdate: Remove redundant INIT_LIST_HEAD in luo_session_alloc
  selftests/liveupdate: add end to end test infrastructure and scripts

3 files changed, 20 insertions, 9 deletions

diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_handover.c
index 175c08a6e41e..6fad9152387a 100644
--- a/kernel/liveupdate/kexec_handover.c
+++ b/kernel/liveupdate/kexec_handover.c
@@ -501,7 +501,7 @@ static int __init kho_preserved_memory_reserve(phys_addr_t phys,
 	struct page *page;
 	u64 sz;
 
-	sz = 1 << (order + PAGE_SHIFT);
+	sz = 1UL << (order + PAGE_SHIFT);
 	page = kho_get_preserved_page(phys, order);
 
 	/* Reserve the memory preserved in KHO in memblock */
diff --git a/kernel/liveupdate/luo_flb.c b/kernel/liveupdate/luo_flb.c
index 5c27134ce7ba..cd715a7c1d99 100644
--- a/kernel/liveupdate/luo_flb.c
+++ b/kernel/liveupdate/luo_flb.c
@@ -133,7 +133,7 @@ static int luo_flb_file_preserve_one(struct liveupdate_flb *flb)
 	return 0;
 }
 
-static void luo_flb_file_unpreserve_one(struct liveupdate_flb *flb)
+void liveupdate_flb_put_outgoing(struct liveupdate_flb *flb)
 {
 	struct luo_flb_private *private = luo_flb_get_private(flb);
 
@@ -168,7 +168,10 @@ static int luo_flb_retrieve_one(struct liveupdate_flb *flb)
 	if (private->incoming.finished)
 		return -ENODATA;
 
-	if (private->incoming.retrieved)
+	if (private->incoming.retrieve_status < 0)
+		return private->incoming.retrieve_status;
+
+	if (private->incoming.retrieve_status > 0)
 		return 0;
 
 	if (!fh->active)
@@ -194,12 +197,13 @@ static int luo_flb_retrieve_one(struct liveupdate_flb *flb)
 
 	err = flb->ops->retrieve(&args);
 	if (err) {
+		private->incoming.retrieve_status = err;
 		module_put(flb->ops->owner);
 		return err;
 	}
 
 	private->incoming.obj = args.obj;
-	private->incoming.retrieved = true;
+	private->incoming.retrieve_status = 1;
 
 	return 0;
 }
@@ -213,7 +217,7 @@ void liveupdate_flb_put_incoming(struct liveupdate_flb *flb)
 		if (!refcount_dec_and_test(&private->incoming.count))
 			return;
 
-		if (!private->incoming.retrieved) {
+		if (private->incoming.retrieve_status <= 0) {
 			int err = luo_flb_retrieve_one(flb);
 
 			if (WARN_ON(err))
@@ -264,7 +268,7 @@ int luo_flb_file_preserve(struct liveupdate_file_handler *fh)
 
 exit_err:
 	list_for_each_entry_continue_reverse(iter, flb_list, list)
-		luo_flb_file_unpreserve_one(iter->flb);
+		liveupdate_flb_put_outgoing(iter->flb);
 	up_read(&luo_register_rwlock);
 
 	return err;
@@ -289,7 +293,7 @@ void luo_flb_file_unpreserve(struct liveupdate_file_handler *fh)
 
 	guard(rwsem_read)(&luo_register_rwlock);
 	list_for_each_entry_reverse(iter, flb_list, list)
-		luo_flb_file_unpreserve_one(iter->flb);
+		liveupdate_flb_put_outgoing(iter->flb);
 }
 
 /**
@@ -544,6 +548,10 @@ int liveupdate_flb_get_outgoing(struct liveupdate_flb *flb, void **objp)
 		return -EOPNOTSUPP;
 
 	guard(mutex)(&private->outgoing.lock);
+	if (!private->outgoing.obj)
+		return -ENOENT;
+
+	refcount_inc(&private->outgoing.count);
 	*objp = private->outgoing.obj;
 
 	return 0;
diff --git a/kernel/liveupdate/luo_session.c b/kernel/liveupdate/luo_session.c
index f38b5b18f3f8..f48e9a4185f9 100644
--- a/kernel/liveupdate/luo_session.c
+++ b/kernel/liveupdate/luo_session.c
@@ -154,7 +154,6 @@ static struct luo_session *luo_session_alloc(const char *name)
 		return ERR_PTR(-ENOMEM);
 
 	strscpy(session->name, name, sizeof(session->name));
-	INIT_LIST_HEAD(&session->file_set.files_list);
 	luo_file_set_init(&session->file_set);
 	INIT_LIST_HEAD(&session->list);
 	mutex_init(&session->mutex);
@@ -316,8 +315,12 @@ static int luo_session_finish(struct luo_session *session,
 			      struct luo_ucmd *ucmd)
 {
 	struct liveupdate_session_finish *argp = ucmd->cmd;
-	int err = luo_session_finish_one(session);
+	int err;
+
+	if (argp->reserved)
+		return -EINVAL;
 
+	err = luo_session_finish_one(session);
 	if (err)
 		return err;