linux-kernel - Re: tty_init_dev: 24 callbacks suppressed

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20121004115157.GA245@x4>
Date:	Thu, 4 Oct 2012 13:51:57 +0200
From:	Markus Trippelsdorf <markus@...ppelsdorf.de>
To:	Borislav Petkov <bp@...64.org>
Cc:	Jiri Slaby <jslaby@...e.cz>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Alan Cox <alan@...rguk.ukuu.org.uk>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: tty_init_dev: 24 callbacks suppressed

On 2012.10.04 at 13:23 +0200, Markus Trippelsdorf wrote:
> On 2012.10.04 at 11:20 +0200, Borislav Petkov wrote:
> > Hi,
> > 
> > I'm seeing this on today's Linus tree:
> > 
> > [   24.048278] tty_init_dev: 24 callbacks suppressed
> > [   45.630349] tty_init_dev: 3 callbacks suppressed
> > 
> > It is either from that WARN_RATELIMIT thing or the printk_ratelimited
> > further below in tty_init_dev but I don't know for sure because the
> > actual text message from both printk's doesn't come out in dmesg - only
> > that something got suppressed.
> > 
> > And it quiets down later, after the machine has finished booting. Still,
> > this doesn't tell me anything about any issue. So what's up?
> 
> I'm seeing the same thing.
> This can be fixed by a slightly modified version of:
> https://patchwork.kernel.org/patch/1339221/

My first patch was wrong. This one should be correct:

diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h
index e11ccb4..d8de255 100644
--- a/include/linux/ratelimit.h
+++ b/include/linux/ratelimit.h
@@ -46,20 +46,17 @@ extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
 #define WARN_ON_RATELIMIT(condition, state)			\
 		WARN_ON((condition) && __ratelimit(state))
 
-#define __WARN_RATELIMIT(condition, state, format...)		\
-({								\
-	int rtn = 0;						\
-	if (unlikely(__ratelimit(state)))			\
-		rtn = WARN(condition, format);			\
-	rtn;							\
-})
-
-#define WARN_RATELIMIT(condition, format...)			\
+#define WARN_RATELIMIT(condition, fmt, ...)			\
 ({								\
 	static DEFINE_RATELIMIT_STATE(_rs,			\
 				      DEFAULT_RATELIMIT_INTERVAL,	\
 				      DEFAULT_RATELIMIT_BURST);	\
-	__WARN_RATELIMIT(condition, &_rs, format);		\
+	int rtn = !!(condition);				\
+								\
+	if (unlikely(rtn && __ratelimit(&_rs)))		\
+		WARN(rtn, fmt, ##__VA_ARGS__);			\
+								\
+	rtn;							\
 })
 
 #else
@@ -67,15 +64,9 @@ extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
 #define WARN_ON_RATELIMIT(condition, state)			\
 	WARN_ON(condition)
 
-#define __WARN_RATELIMIT(condition, state, format...)		\
-({								\
-	int rtn = WARN(condition, format);			\
-	rtn;							\
-})
-
-#define WARN_RATELIMIT(condition, format...)			\
+#define WARN_RATELIMIT(condition, fmt, ...)			\
 ({								\
-	int rtn = WARN(condition, format);			\
+	int rtn = WARN(condition, fmt, ##__VA_ARGS__);		\
 	rtn;							\
 })
 
-- 
Markus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/