5 files changed, 46 insertions, 6 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index c1c7a9d78722..ce727047ee87 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -79,7 +79,7 @@ int nfs_wait_bit_killable(void *word)
 {
         if (fatal_signal_pending(current))
                 return -ERESTARTSYS;
-        freezable_schedule();
+        freezable_schedule_unsafe();
         return 0;
 }
 EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index 43ea96ced28c..ce90eb4775c2 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -33,7 +33,7 @@ nfs3_rpc_wrapper(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
                 res = rpc_call_sync(clnt, msg, flags);
                 if (res != -EJUKEBOX)
                         break;
-                freezable_schedule_timeout_killable(NFS_JUKEBOX_RETRY_TIME);
+                freezable_schedule_timeout_killable_unsafe(NFS_JUKEBOX_RETRY_TIME);
                 res = -ERESTARTSYS;
         } while (!fatal_signal_pending(current));
         return res;
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 8fbc10054115..9b18af167815 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -268,7 +268,7 @@ static int nfs4_delay(struct rpc_clnt *clnt, long *timeout)
                 *timeout = NFS4_POLL_RETRY_MIN;
         if (*timeout > NFS4_POLL_RETRY_MAX)
                 *timeout = NFS4_POLL_RETRY_MAX;
-        freezable_schedule_timeout_killable(*timeout);
+        freezable_schedule_timeout_killable_unsafe(*timeout);
         if (fatal_signal_pending(current))
                 res = -ERESTARTSYS;
         *timeout <<= 1;
@@ -4528,7 +4528,7 @@ int nfs4_proc_delegreturn(struct inode *inode, struct rpc_cred *cred, const nfs4
 static unsigned long
 nfs4_set_lock_task_retry(unsigned long timeout)
 {
-        freezable_schedule_timeout_killable(timeout);
+        freezable_schedule_timeout_killable_unsafe(timeout);
         timeout <<= 1;
         if (timeout > NFS4_LOCK_MAXTIMEOUT)
                 return NFS4_LOCK_MAXTIMEOUT;
diff --git a/include/linux/freezer.h b/include/linux/freezer.h
index e70df40d84f6..5b31e21c485f 100644
--- a/include/linux/freezer.h
+++ b/include/linux/freezer.h
@@ -46,7 +46,11 @@ extern int freeze_kernel_threads(void);
 extern void thaw_processes(void);
 extern void thaw_kernel_threads(void);
 
-static inline bool try_to_freeze(void)
+/*
+ * DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION
+ * If try_to_freeze causes a lockdep warning it means the caller may deadlock
+ */
+static inline bool try_to_freeze_unsafe(void)
 {
         might_sleep();
         if (likely(!freezing(current)))
@@ -54,6 +58,11 @@ static inline bool try_to_freeze(void)
         return __refrigerator(false);
 }
 
+static inline bool try_to_freeze(void)
+{
+        return try_to_freeze_unsafe();
+}
+
 extern bool freeze_task(struct task_struct *p);
 extern bool set_freezable(void);
 
@@ -115,6 +124,14 @@ static inline void freezer_count(void)
         try_to_freeze();
 }
 
+/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */
+static inline void freezer_count_unsafe(void)
+{
+        current->flags &= ~PF_FREEZER_SKIP;
+        smp_mb();
+        try_to_freeze_unsafe();
+}
+
 /**
  * freezer_should_skip - whether to skip a task when determining frozen
  *                       state is reached
@@ -152,6 +169,14 @@ static inline bool freezer_should_skip(struct task_struct *p)
         freezer_count();                                                \
 })
 
+/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */
+#define freezable_schedule_unsafe()                                     \
+({                                                                      \
+        freezer_do_not_count();                                         \
+        schedule();                                                     \
+        freezer_count_unsafe();                                         \
+})
+
 /* Like schedule_timeout_killable(), but should not block the freezer. */
 #define freezable_schedule_timeout_killable(timeout)                    \
 ({                                                                      \
@@ -162,6 +187,16 @@ static inline bool freezer_should_skip(struct task_struct *p)
         __retval;                                                       \
 })
 
+/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */
+#define freezable_schedule_timeout_killable_unsafe(timeout)             \
+({                                                                      \
+        long __retval;                                                  \
+        freezer_do_not_count();                                         \
+        __retval = schedule_timeout_killable(timeout);                  \
+        freezer_count_unsafe();                                         \
+        __retval;                                                       \
+})
+
 /*
  * Freezer-friendly wrappers around wait_event_interruptible(),
  * wait_event_killable() and wait_event_interruptible_timeout(), originally
@@ -225,9 +260,14 @@ static inline void set_freezable(void) {}
 
 #define freezable_schedule()  schedule()
 
+#define freezable_schedule_unsafe()  schedule()
+
 #define freezable_schedule_timeout_killable(timeout)                    \
         schedule_timeout_killable(timeout)
 
+#define freezable_schedule_timeout_killable_unsafe(timeout)             \
+        schedule_timeout_killable(timeout)
+
 #define wait_event_freezable(wq, condition)                             \
                 wait_event_interruptible(wq, condition)
 
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index f8529fc8e542..8dcfadcef5d3 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -254,7 +254,7 @@ static int rpc_wait_bit_killable(void *word)
 {
         if (fatal_signal_pending(current))
                 return -ERESTARTSYS;
-        freezable_schedule();
+        freezable_schedule_unsafe();
         return 0;
 }