Patch "cifs: Ratelimit kernel log messages" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

cifs: Ratelimit kernel log messages

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
cifs-ratelimit-kernel-log-messages.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Jamie Bainbridge <[email protected]>
Date: Sat, 7 Nov 2015 22:13:49 +1000
Subject: cifs: Ratelimit kernel log messages

From: Jamie Bainbridge <[email protected]>

commit ec7147a99e33a9e4abad6fc6e1b40d15df045d53 upstream.

Under some conditions, CIFS can repeatedly call the cifs_dbg() logging wrapper. If done rapidly enough, the console framebuffer can softlockup or "rcu_sched self-detected stall". Apply the built-in log ratelimiters to prevent such hangs.

---
 fs/cifs/cifs_debug.c |    2 +-
 fs/cifs/cifs_debug.h |    9 ++++-----
 2 files changed, 5 insertions(+), 6 deletions(-)

@@ -50,7 +50,7 @@ void cifs_vfs_err(const char *fmt, ...)
 	vaf.fmt = fmt;
 	vaf.va = &args;
 
-	pr_err("CIFS VFS: %pV", &vaf);
+	pr_err_ratelimited("CIFS VFS: %pV", &vaf);
 
 	va_end(args);
 }

@@ -51,14 +51,13 @@ __printf(1, 2) void cifs_vfs_err(const c
 /* information message: e.g., configuration, major event */
 #define cifs_dbg(type, fmt, ...)					\
 do {									\
-	if (type == FYI) {						\
-		if (cifsFYI & CIFS_INFO) {				\
-			pr_debug("%s: " fmt, __FILE__, ##__VA_ARGS__);	\
-		}							\
+	if (type == FYI && cifsFYI & CIFS_INFO) {			\
+		pr_debug_ratelimited("%s: "				\
+			    fmt, __FILE__, ##__VA_ARGS__);		\
 	} else if (type == VFS) {					\
 		cifs_vfs_err(fmt, ##__VA_ARGS__);			\
 	} else if (type == NOISY && type != 0) {			\
-		pr_debug(fmt, ##__VA_ARGS__);				\
+		pr_debug_ratelimited(fmt, ##__VA_ARGS__);		\
 	}								\
 } while (0)
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/cifs-ratelimit-kernel-log-messages.patch