From 0e25498f8cd43c1b5aa327f373dd094e9a006da7 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Mon, 28 Jun 2021 14:52:01 -0500
Subject: exit: Add and use make_task_dead.

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 tools/objtool/check.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'tools')

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 21735829b860..e6ab5687770b 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -168,6 +168,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"panic",
 		"do_exit",
 		"do_task_dead",
+		"make_task_dead",
 		"__module_put_and_exit",
 		"complete_and_exit",
 		"__reiserfs_panic",
@@ -175,7 +176,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"fortify_panic",
 		"usercopy_abort",
 		"machine_real_restart",
-		"rewind_stack_do_exit",
+		"rewind_stack_and_make_dead"
 		"kunit_try_catch_throw",
 		"xen_start_kernel",
 		"cpu_bringup_and_idle",
-- 
cgit v1.2.3


From bbda86e988d4c124e4cfa816291cbd583ae8bfb1 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Mon, 22 Nov 2021 10:27:36 -0600
Subject: exit: Implement kthread_exit

The way the per task_struct exit_code is used by kernel threads is not
quite compatible how it is used by userspace applications.  The low
byte of the userspace exit_code value encodes the exit signal.  While
kthreads just use the value as an int holding ordinary kernel function
exit status like -EPERM.

Add kthread_exit to clearly separate the two kinds of uses.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 include/linux/kthread.h |  1 +
 kernel/kthread.c        | 23 +++++++++++++++++++----
 tools/objtool/check.c   |  1 +
 3 files changed, 21 insertions(+), 4 deletions(-)

(limited to 'tools')

diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index 346b0f269161..22c43d419687 100644
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -70,6 +70,7 @@ void *kthread_probe_data(struct task_struct *k);
 int kthread_park(struct task_struct *k);
 void kthread_unpark(struct task_struct *k);
 void kthread_parkme(void);
+void kthread_exit(long result) __noreturn;
 
 int kthreadd(void *unused);
 extern struct task_struct *kthreadd_task;
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 7113003fab63..77b7c3f23f18 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -268,6 +268,21 @@ void kthread_parkme(void)
 }
 EXPORT_SYMBOL_GPL(kthread_parkme);
 
+/**
+ * kthread_exit - Cause the current kthread return @result to kthread_stop().
+ * @result: The integer value to return to kthread_stop().
+ *
+ * While kthread_exit can be called directly, it exists so that
+ * functions which do some additional work in non-modular code such as
+ * module_put_and_kthread_exit can be implemented.
+ *
+ * Does not return.
+ */
+void __noreturn kthread_exit(long result)
+{
+	do_exit(result);
+}
+
 static int kthread(void *_create)
 {
 	static const struct sched_param param = { .sched_priority = 0 };
@@ -286,13 +301,13 @@ static int kthread(void *_create)
 	done = xchg(&create->done, NULL);
 	if (!done) {
 		kfree(create);
-		do_exit(-EINTR);
+		kthread_exit(-EINTR);
 	}
 
 	if (!self) {
 		create->result = ERR_PTR(-ENOMEM);
 		complete(done);
-		do_exit(-ENOMEM);
+		kthread_exit(-ENOMEM);
 	}
 
 	self->threadfn = threadfn;
@@ -326,7 +341,7 @@ static int kthread(void *_create)
 		__kthread_parkme(self);
 		ret = threadfn(data);
 	}
-	do_exit(ret);
+	kthread_exit(ret);
 }
 
 /* called from kernel_clone() to get node information for about to be created task */
@@ -627,7 +642,7 @@ EXPORT_SYMBOL_GPL(kthread_park);
  * instead of calling wake_up_process(): the thread will exit without
  * calling threadfn().
  *
- * If threadfn() may call do_exit() itself, the caller must ensure
+ * If threadfn() may call kthread_exit() itself, the caller must ensure
  * task_struct can't go away.
  *
  * Returns the result of threadfn(), or %-EINTR if wake_up_process()
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index e6ab5687770b..90108fe5610d 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -168,6 +168,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"panic",
 		"do_exit",
 		"do_task_dead",
+		"kthread_exit",
 		"make_task_dead",
 		"__module_put_and_exit",
 		"complete_and_exit",
-- 
cgit v1.2.3


From ca3574bd653aba234a4b31955f2778947403be16 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Fri, 3 Dec 2021 11:00:19 -0600
Subject: exit: Rename module_put_and_exit to module_put_and_kthread_exit

Update module_put_and_exit to call kthread_exit instead of do_exit.

Change the name to reflect this change in functionality.  All of the
users of module_put_and_exit are causing the current kthread to exit
so this change makes it clear what is happening.  There is no
functional change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 crypto/algboss.c          | 4 ++--
 fs/cifs/connect.c         | 2 +-
 fs/nfs/callback.c         | 4 ++--
 fs/nfs/nfs4state.c        | 2 +-
 fs/nfsd/nfssvc.c          | 2 +-
 include/linux/module.h    | 6 +++---
 kernel/module.c           | 6 +++---
 net/bluetooth/bnep/core.c | 2 +-
 net/bluetooth/cmtp/core.c | 2 +-
 net/bluetooth/hidp/core.c | 2 +-
 tools/objtool/check.c     | 2 +-
 11 files changed, 17 insertions(+), 17 deletions(-)

(limited to 'tools')

diff --git a/crypto/algboss.c b/crypto/algboss.c
index 1814d2c5188a..eb5fe84efb83 100644
--- a/crypto/algboss.c
+++ b/crypto/algboss.c
@@ -67,7 +67,7 @@ out:
 	complete_all(&param->larval->completion);
 	crypto_alg_put(&param->larval->alg);
 	kfree(param);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 }
 
 static int cryptomgr_schedule_probe(struct crypto_larval *larval)
@@ -190,7 +190,7 @@ skiptest:
 	crypto_alg_tested(param->driver, err);
 
 	kfree(param);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 }
 
 static int cryptomgr_schedule_test(struct crypto_alg *alg)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 82577a7a5bb1..39fbe9acbf51 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1139,7 +1139,7 @@ next_pdu:
 	}
 
 	memalloc_noreclaim_restore(noreclaim_flag);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 }
 
 /*
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 86d856de1389..3c86a559a321 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -93,7 +93,7 @@ nfs4_callback_svc(void *vrqstp)
 		svc_process(rqstp);
 	}
 	svc_exit_thread(rqstp);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 	return 0;
 }
 
@@ -137,7 +137,7 @@ nfs41_callback_svc(void *vrqstp)
 		}
 	}
 	svc_exit_thread(rqstp);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 	return 0;
 }
 
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index ecc4594299d6..ea41af731978 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -2689,6 +2689,6 @@ static int nfs4_run_state_manager(void *ptr)
 	allow_signal(SIGKILL);
 	nfs4_state_manager(clp);
 	nfs_put_client(clp);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 	return 0;
 }
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 80431921e5d7..5ce9f14318c4 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -986,7 +986,7 @@ out:
 
 	/* Release module */
 	mutex_unlock(&nfsd_mutex);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 	return 0;
 }
 
diff --git a/include/linux/module.h b/include/linux/module.h
index c9f1200b2312..f03be97e9ec1 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -595,9 +595,9 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
 /* Look for this name: can be of form module:name. */
 unsigned long module_kallsyms_lookup_name(const char *name);
 
-extern void __noreturn __module_put_and_exit(struct module *mod,
+extern void __noreturn __module_put_and_kthread_exit(struct module *mod,
 			long code);
-#define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code)
+#define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
 
 #ifdef CONFIG_MODULE_UNLOAD
 int module_refcount(struct module *mod);
@@ -790,7 +790,7 @@ static inline int unregister_module_notifier(struct notifier_block *nb)
 	return 0;
 }
 
-#define module_put_and_exit(code) do_exit(code)
+#define module_put_and_kthread_exit(code) kthread_exit(code)
 
 static inline void print_modules(void)
 {
diff --git a/kernel/module.c b/kernel/module.c
index 84a9141a5e15..a3aa00bf270d 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -337,12 +337,12 @@ static inline void add_taint_module(struct module *mod, unsigned flag,
  * A thread that wants to hold a reference to a module only while it
  * is running can call this to safely exit.  nfsd and lockd use this.
  */
-void __noreturn __module_put_and_exit(struct module *mod, long code)
+void __noreturn __module_put_and_kthread_exit(struct module *mod, long code)
 {
 	module_put(mod);
-	do_exit(code);
+	kthread_exit(code);
 }
-EXPORT_SYMBOL(__module_put_and_exit);
+EXPORT_SYMBOL(__module_put_and_kthread_exit);
 
 /* Find a module section: 0 means not found. */
 static unsigned int find_sec(const struct load_info *info, const char *name)
diff --git a/net/bluetooth/bnep/core.c b/net/bluetooth/bnep/core.c
index c9add7753b9f..40baa6b7321a 100644
--- a/net/bluetooth/bnep/core.c
+++ b/net/bluetooth/bnep/core.c
@@ -535,7 +535,7 @@ static int bnep_session(void *arg)
 
 	up_write(&bnep_session_sem);
 	free_netdev(dev);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 	return 0;
 }
 
diff --git a/net/bluetooth/cmtp/core.c b/net/bluetooth/cmtp/core.c
index 0a2d78e811cf..9bfded6b74b3 100644
--- a/net/bluetooth/cmtp/core.c
+++ b/net/bluetooth/cmtp/core.c
@@ -323,7 +323,7 @@ static int cmtp_session(void *arg)
 	up_write(&cmtp_session_sem);
 
 	kfree(session);
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 	return 0;
 }
 
diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 80848dfc01db..5940744a8cd8 100644
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -1305,7 +1305,7 @@ static int hidp_session_thread(void *arg)
 	l2cap_unregister_user(session->conn, &session->user);
 	hidp_session_put(session);
 
-	module_put_and_exit(0);
+	module_put_and_kthread_exit(0);
 	return 0;
 }
 
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 90108fe5610d..120e9598c11a 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -170,7 +170,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"do_task_dead",
 		"kthread_exit",
 		"make_task_dead",
-		"__module_put_and_exit",
+		"__module_put_and_kthread_exit",
 		"complete_and_exit",
 		"__reiserfs_panic",
 		"lbug_with_loc",
-- 
cgit v1.2.3


From cead18552660702a4a46f58e65188fe5f36e9dfe Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Mon, 22 Nov 2021 11:15:19 -0600
Subject: exit: Rename complete_and_exit to kthread_complete_and_exit

Update complete_and_exit to call kthread_exit instead of do_exit.

Change the name to reflect this change in functionality.  All of the
users of complete_and_exit are causing the current kthread to exit so
this change makes it clear what is happening.

Move the implementation of kthread_complete_and_exit from
kernel/exit.c to to kernel/kthread.c.  As this function is kthread
specific it makes most sense to live with the kthread functions.

There are no functional change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/net/wireless/rsi/rsi_91x_coex.c      |  2 +-
 drivers/net/wireless/rsi/rsi_91x_main.c      |  2 +-
 drivers/net/wireless/rsi/rsi_91x_sdio_ops.c  |  2 +-
 drivers/net/wireless/rsi/rsi_91x_usb_ops.c   |  2 +-
 drivers/pnp/pnpbios/core.c                   |  6 +++---
 drivers/staging/rts5208/rtsx.c               | 16 ++++++++--------
 drivers/usb/atm/usbatm.c                     |  2 +-
 drivers/usb/gadget/function/f_mass_storage.c |  2 +-
 fs/jffs2/background.c                        |  2 +-
 include/linux/kernel.h                       |  1 -
 include/linux/kthread.h                      |  1 +
 kernel/exit.c                                |  9 ---------
 kernel/kthread.c                             | 21 +++++++++++++++++++++
 lib/kunit/try-catch.c                        |  4 ++--
 tools/objtool/check.c                        |  2 +-
 15 files changed, 43 insertions(+), 31 deletions(-)

(limited to 'tools')

diff --git a/drivers/net/wireless/rsi/rsi_91x_coex.c b/drivers/net/wireless/rsi/rsi_91x_coex.c
index a0c5d02ae88c..8a3d86897ea8 100644
--- a/drivers/net/wireless/rsi/rsi_91x_coex.c
+++ b/drivers/net/wireless/rsi/rsi_91x_coex.c
@@ -63,7 +63,7 @@ static void rsi_coex_scheduler_thread(struct rsi_common *common)
 		rsi_coex_sched_tx_pkts(coex_cb);
 	} while (atomic_read(&coex_cb->coex_tx_thread.thread_done) == 0);
 
-	complete_and_exit(&coex_cb->coex_tx_thread.completion, 0);
+	kthread_complete_and_exit(&coex_cb->coex_tx_thread.completion, 0);
 }
 
 int rsi_coex_recv_pkt(struct rsi_common *common, u8 *msg)
diff --git a/drivers/net/wireless/rsi/rsi_91x_main.c b/drivers/net/wireless/rsi/rsi_91x_main.c
index f1bf71e6c608..c7f5cec5e446 100644
--- a/drivers/net/wireless/rsi/rsi_91x_main.c
+++ b/drivers/net/wireless/rsi/rsi_91x_main.c
@@ -260,7 +260,7 @@ static void rsi_tx_scheduler_thread(struct rsi_common *common)
 		if (common->init_done)
 			rsi_core_qos_processor(common);
 	} while (atomic_read(&common->tx_thread.thread_done) == 0);
-	complete_and_exit(&common->tx_thread.completion, 0);
+	kthread_complete_and_exit(&common->tx_thread.completion, 0);
 }
 
 #ifdef CONFIG_RSI_COEX
diff --git a/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c b/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
index 8ace1874e5cb..b2b47a0abcbf 100644
--- a/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
+++ b/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
@@ -75,7 +75,7 @@ void rsi_sdio_rx_thread(struct rsi_common *common)
 
 	rsi_dbg(INFO_ZONE, "%s: Terminated SDIO RX thread\n", __func__);
 	atomic_inc(&sdev->rx_thread.thread_done);
-	complete_and_exit(&sdev->rx_thread.completion, 0);
+	kthread_complete_and_exit(&sdev->rx_thread.completion, 0);
 }
 
 /**
diff --git a/drivers/net/wireless/rsi/rsi_91x_usb_ops.c b/drivers/net/wireless/rsi/rsi_91x_usb_ops.c
index 4ffcdde1acb1..5130b0e72adc 100644
--- a/drivers/net/wireless/rsi/rsi_91x_usb_ops.c
+++ b/drivers/net/wireless/rsi/rsi_91x_usb_ops.c
@@ -56,6 +56,6 @@ void rsi_usb_rx_thread(struct rsi_common *common)
 out:
 	rsi_dbg(INFO_ZONE, "%s: Terminated thread\n", __func__);
 	skb_queue_purge(&dev->rx_q);
-	complete_and_exit(&dev->rx_thread.completion, 0);
+	kthread_complete_and_exit(&dev->rx_thread.completion, 0);
 }
 
diff --git a/drivers/pnp/pnpbios/core.c b/drivers/pnp/pnpbios/core.c
index 669ef4700c1a..f7e86ae9f72f 100644
--- a/drivers/pnp/pnpbios/core.c
+++ b/drivers/pnp/pnpbios/core.c
@@ -160,7 +160,7 @@ static int pnp_dock_thread(void *unused)
 			 * No dock to manage
 			 */
 		case PNP_FUNCTION_NOT_SUPPORTED:
-			complete_and_exit(&unload_sem, 0);
+			kthread_complete_and_exit(&unload_sem, 0);
 		case PNP_SYSTEM_NOT_DOCKED:
 			d = 0;
 			break;
@@ -170,7 +170,7 @@ static int pnp_dock_thread(void *unused)
 		default:
 			pnpbios_print_status("pnp_dock_thread", status);
 			printk(KERN_WARNING "PnPBIOS: disabling dock monitoring.\n");
-			complete_and_exit(&unload_sem, 0);
+			kthread_complete_and_exit(&unload_sem, 0);
 		}
 		if (d != docked) {
 			if (pnp_dock_event(d, &now) == 0) {
@@ -183,7 +183,7 @@ static int pnp_dock_thread(void *unused)
 			}
 		}
 	}
-	complete_and_exit(&unload_sem, 0);
+	kthread_complete_and_exit(&unload_sem, 0);
 }
 
 static int pnpbios_get_resources(struct pnp_dev *dev)
diff --git a/drivers/staging/rts5208/rtsx.c b/drivers/staging/rts5208/rtsx.c
index 91fcf85e150a..5a58dac76c88 100644
--- a/drivers/staging/rts5208/rtsx.c
+++ b/drivers/staging/rts5208/rtsx.c
@@ -450,13 +450,13 @@ skip_for_abort:
 	 * after the down() -- that's necessary for the thread-shutdown
 	 * case.
 	 *
-	 * complete_and_exit() goes even further than this -- it is safe in
-	 * the case that the thread of the caller is going away (not just
-	 * the structure) -- this is necessary for the module-remove case.
-	 * This is important in preemption kernels, which transfer the flow
-	 * of execution immediately upon a complete().
+	 * kthread_complete_and_exit() goes even further than this --
+	 * it is safe in the case that the thread of the caller is going away
+	 * (not just the structure) -- this is necessary for the module-remove
+	 * case.  This is important in preemption kernels, which transfer the
+	 * flow of execution immediately upon a complete().
 	 */
-	complete_and_exit(&dev->control_exit, 0);
+	kthread_complete_and_exit(&dev->control_exit, 0);
 }
 
 static int rtsx_polling_thread(void *__dev)
@@ -501,7 +501,7 @@ static int rtsx_polling_thread(void *__dev)
 		mutex_unlock(&dev->dev_mutex);
 	}
 
-	complete_and_exit(&dev->polling_exit, 0);
+	kthread_complete_and_exit(&dev->polling_exit, 0);
 }
 
 /*
@@ -682,7 +682,7 @@ static int rtsx_scan_thread(void *__dev)
 		/* Should we unbind if no devices were detected? */
 	}
 
-	complete_and_exit(&dev->scanning_done, 0);
+	kthread_complete_and_exit(&dev->scanning_done, 0);
 }
 
 static void rtsx_init_options(struct rtsx_chip *chip)
diff --git a/drivers/usb/atm/usbatm.c b/drivers/usb/atm/usbatm.c
index da17be1ef64e..e3a49d837609 100644
--- a/drivers/usb/atm/usbatm.c
+++ b/drivers/usb/atm/usbatm.c
@@ -969,7 +969,7 @@ static int usbatm_do_heavy_init(void *arg)
 	instance->thread = NULL;
 	mutex_unlock(&instance->serialize);
 
-	complete_and_exit(&instance->thread_exited, ret);
+	kthread_complete_and_exit(&instance->thread_exited, ret);
 }
 
 static int usbatm_heavy_init(struct usbatm_data *instance)
diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index 752439690fda..46dd11dcb3a8 100644
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -2547,7 +2547,7 @@ static int fsg_main_thread(void *common_)
 	up_write(&common->filesem);
 
 	/* Let fsg_unbind() know the thread has exited */
-	complete_and_exit(&common->thread_notifier, 0);
+	kthread_complete_and_exit(&common->thread_notifier, 0);
 }
 
 
diff --git a/fs/jffs2/background.c b/fs/jffs2/background.c
index 2b4d5013dc5d..6da92ecaf66d 100644
--- a/fs/jffs2/background.c
+++ b/fs/jffs2/background.c
@@ -161,5 +161,5 @@ static int jffs2_garbage_collect_thread(void *_c)
 	spin_lock(&c->erase_completion_lock);
 	c->gc_task = NULL;
 	spin_unlock(&c->erase_completion_lock);
-	complete_and_exit(&c->gc_thread_exit, 0);
+	kthread_complete_and_exit(&c->gc_thread_exit, 0);
 }
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 77755ac3e189..055eb203c00e 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -187,7 +187,6 @@ static inline void might_fault(void) { }
 #endif
 
 void do_exit(long error_code) __noreturn;
-void complete_and_exit(struct completion *, long) __noreturn;
 
 extern int num_to_str(char *buf, int size,
 		      unsigned long long num, unsigned int width);
diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index 22c43d419687..d86a7e3b9a52 100644
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -71,6 +71,7 @@ int kthread_park(struct task_struct *k);
 void kthread_unpark(struct task_struct *k);
 void kthread_parkme(void);
 void kthread_exit(long result) __noreturn;
+void kthread_complete_and_exit(struct completion *, long) __noreturn;
 
 int kthreadd(void *unused);
 extern struct task_struct *kthreadd_task;
diff --git a/kernel/exit.c b/kernel/exit.c
index 57afac845a0a..6c4b04531f17 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -891,15 +891,6 @@ void __noreturn make_task_dead(int signr)
 	do_exit(signr);
 }
 
-void complete_and_exit(struct completion *comp, long code)
-{
-	if (comp)
-		complete(comp);
-
-	do_exit(code);
-}
-EXPORT_SYMBOL(complete_and_exit);
-
 SYSCALL_DEFINE1(exit, int, error_code)
 {
 	do_exit((error_code&0xff)<<8);
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 77b7c3f23f18..4388d6694a7f 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -283,6 +283,27 @@ void __noreturn kthread_exit(long result)
 	do_exit(result);
 }
 
+/**
+ * kthread_complete_and exit - Exit the current kthread.
+ * @comp: Completion to complete
+ * @code: The integer value to return to kthread_stop().
+ *
+ * If present complete @comp and the reuturn code to kthread_stop().
+ *
+ * A kernel thread whose module may be removed after the completion of
+ * @comp can use this function exit safely.
+ *
+ * Does not return.
+ */
+void __noreturn kthread_complete_and_exit(struct completion *comp, long code)
+{
+	if (comp)
+		complete(comp);
+
+	kthread_exit(code);
+}
+EXPORT_SYMBOL(kthread_complete_and_exit);
+
 static int kthread(void *_create)
 {
 	static const struct sched_param param = { .sched_priority = 0 };
diff --git a/lib/kunit/try-catch.c b/lib/kunit/try-catch.c
index 0dd434e40487..be38a2c5ecc2 100644
--- a/lib/kunit/try-catch.c
+++ b/lib/kunit/try-catch.c
@@ -17,7 +17,7 @@
 void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch)
 {
 	try_catch->try_result = -EFAULT;
-	complete_and_exit(try_catch->try_completion, -EFAULT);
+	kthread_complete_and_exit(try_catch->try_completion, -EFAULT);
 }
 EXPORT_SYMBOL_GPL(kunit_try_catch_throw);
 
@@ -27,7 +27,7 @@ static int kunit_generic_run_threadfn_adapter(void *data)
 
 	try_catch->try(try_catch->context);
 
-	complete_and_exit(try_catch->try_completion, 0);
+	kthread_complete_and_exit(try_catch->try_completion, 0);
 }
 
 static unsigned long kunit_test_timeout(void)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 120e9598c11a..282273a1ffa5 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -171,7 +171,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"kthread_exit",
 		"make_task_dead",
 		"__module_put_and_kthread_exit",
-		"complete_and_exit",
+		"kthread_complete_and_exit",
 		"__reiserfs_panic",
 		"lbug_with_loc",
 		"fortify_panic",
-- 
cgit v1.2.3


From 1fb466dff904e4a72282af336f2c355f011eec61 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Wed, 15 Dec 2021 11:24:50 -0600
Subject: objtool: Add a missing comma to avoid string concatenation

Recently the kbuild robot reported two new errors:

>> lib/kunit/kunit-example-test.o: warning: objtool: .text.unlikely: unexpected end of section
>> arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_opcodes()

I don't know why they did not occur in my test setup but after digging
it I realized I had accidentally dropped a comma in
tools/objtool/check.c when I renamed rewind_stack_do_exit to
rewind_stack_and_make_dead.

Add that comma back to fix objtool errors.

Link: https://lkml.kernel.org/r/202112140949.Uq5sFKR1-lkp@intel.com
Fixes: 0e25498f8cd4 ("exit: Add and use make_task_dead.")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 tools/objtool/check.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'tools')

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 282273a1ffa5..3fc2c57f6124 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -177,7 +177,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"fortify_panic",
 		"usercopy_abort",
 		"machine_real_restart",
-		"rewind_stack_and_make_dead"
+		"rewind_stack_and_make_dead",
 		"kunit_try_catch_throw",
 		"xen_start_kernel",
 		"cpu_bringup_and_idle",
-- 
cgit v1.2.3