3 files changed, 23 insertions, 13 deletions

diff --git a/drivers/md/bcache/closure.c b/drivers/md/bcache/closure.c
index 73f5319295bc..c12cd809ab19 100644
--- a/drivers/md/bcache/closure.c
+++ b/drivers/md/bcache/closure.c
@@ -105,8 +105,14 @@ struct closure_syncer {
 
 static void closure_sync_fn(struct closure *cl)
 {
-	cl->s->done = 1;
-	wake_up_process(cl->s->task);
+	struct closure_syncer *s = cl->s;
+	struct task_struct *p;
+
+	rcu_read_lock();
+	p = READ_ONCE(s->task);
+	s->done = 1;
+	wake_up_process(p);
+	rcu_read_unlock();
 }
 
 void __sched __closure_sync(struct closure *cl)
diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c
index 8b123be05254..336f43910383 100644
--- a/drivers/md/bcache/debug.c
+++ b/drivers/md/bcache/debug.c
@@ -178,10 +178,9 @@ static ssize_t bch_dump_read(struct file *file, char __user *buf,
 	while (size) {
 		struct keybuf_key *w;
 		unsigned int bytes = min(i->bytes, size);
-		int err = copy_to_user(buf, i->buf, bytes);
 
-		if (err)
-			return err;
+		if (copy_to_user(buf, i->buf, bytes))
+			return -EFAULT;
 
 		ret	 += bytes;
 		buf	 += bytes;
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 9f0826712845..627dcea0f5b6 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -23,24 +23,28 @@ static const char * const bch_cache_modes[] = {
 	"writethrough",
 	"writeback",
 	"writearound",
-	"none"
+	"none",
+	NULL
 };
 
 /* Default is 0 ("auto") */
 static const char * const bch_stop_on_failure_modes[] = {
 	"auto",
-	"always"
+	"always",
+	NULL
 };
 
 static const char * const cache_replacement_policies[] = {
 	"lru",
 	"fifo",
-	"random"
+	"random",
+	NULL
 };
 
 static const char * const error_actions[] = {
 	"unregister",
-	"panic"
+	"panic",
+	NULL
 };
 
 write_attribute(attach);
@@ -338,7 +342,7 @@ STORE(__cached_dev)
 	}
 
 	if (attr == &sysfs_cache_mode) {
-		v = sysfs_match_string(bch_cache_modes, buf);
+		v = __sysfs_match_string(bch_cache_modes, -1, buf);
 		if (v < 0)
 			return v;
 
@@ -349,7 +353,7 @@ STORE(__cached_dev)
 	}
 
 	if (attr == &sysfs_stop_when_cache_set_failed) {
-		v = sysfs_match_string(bch_stop_on_failure_modes, buf);
+		v = __sysfs_match_string(bch_stop_on_failure_modes, -1, buf);
 		if (v < 0)
 			return v;
 
@@ -816,7 +820,7 @@ STORE(__bch_cache_set)
 			    0, UINT_MAX);
 
 	if (attr == &sysfs_errors) {
-		v = sysfs_match_string(error_actions, buf);
+		v = __sysfs_match_string(error_actions, -1, buf);
 		if (v < 0)
 			return v;
 
@@ -960,6 +964,7 @@ KTYPE(bch_cache_set_internal);
 
 static int __bch_cache_cmp(const void *l, const void *r)
 {
+	cond_resched();
 	return *((uint16_t *)r) - *((uint16_t *)l);
 }
 
@@ -1088,7 +1093,7 @@ STORE(__bch_cache)
 	}
 
 	if (attr == &sysfs_cache_replacement_policy) {
-		v = sysfs_match_string(cache_replacement_policies, buf);
+		v = __sysfs_match_string(cache_replacement_policies, -1, buf);
 		if (v < 0)
 			return v;