From 93e78419ce07dc9195f8b9c472f1f17cd7ec6a02 Mon Sep 17 00:00:00 2001
From: Jonathan Corbet <corbet@lwn.net>
Date: Fri, 27 Mar 2009 12:24:31 -0600
Subject: [PATCH] --- yaml --- r: 138619 b: refs/heads/master c:
 4a6a4499693a419a20559c41e33a7bd70bf20a6f h: refs/heads/master i:   138617:
 feed340bf40aaf157d420c8611f2ca2a84f478df   138615:
 560714f6dcafa5b39f65389d811635a6a8b8d1eb v: v3

---
 [refs]                   |  2 +-
 trunk/fs/fcntl.c         | 10 +++++++---
 trunk/include/linux/fs.h |  2 +-
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/[refs] b/[refs]
index 46d33d378cf3..1e35f199c91b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 996ff68d8b358885c1de82a45517c607999947c7
+refs/heads/master: 4a6a4499693a419a20559c41e33a7bd70bf20a6f
diff --git a/trunk/fs/fcntl.c b/trunk/fs/fcntl.c
index d865ca66ccba..cc8e4de2fee5 100644
--- a/trunk/fs/fcntl.c
+++ b/trunk/fs/fcntl.c
@@ -531,6 +531,12 @@ int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fap
 		if (!new)
 			return -ENOMEM;
 	}
+
+	/*
+	 * We need to take f_lock first since it's not an IRQ-safe
+	 * lock.
+	 */
+	spin_lock(&filp->f_lock);
 	write_lock_irq(&fasync_lock);
 	for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
 		if (fa->fa_file == filp) {
@@ -555,14 +561,12 @@ int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fap
 		result = 1;
 	}
 out:
-	/* Fix up FASYNC bit while still holding fasync_lock */
-	spin_lock(&filp->f_lock);
 	if (on)
 		filp->f_flags |= FASYNC;
 	else
 		filp->f_flags &= ~FASYNC;
-	spin_unlock(&filp->f_lock);
 	write_unlock_irq(&fasync_lock);
+	spin_unlock(&filp->f_lock);
 	return result;
 }
 
diff --git a/trunk/include/linux/fs.h b/trunk/include/linux/fs.h
index 7428c6d35e65..2f13c1d77812 100644
--- a/trunk/include/linux/fs.h
+++ b/trunk/include/linux/fs.h
@@ -848,7 +848,7 @@ struct file {
 #define f_dentry	f_path.dentry
 #define f_vfsmnt	f_path.mnt
 	const struct file_operations	*f_op;
-	spinlock_t		f_lock;  /* f_ep_links, f_flags */
+	spinlock_t		f_lock;  /* f_ep_links, f_flags, no IRQ */
 	atomic_long_t		f_count;
 	unsigned int 		f_flags;
 	fmode_t			f_mode;