linux-kernel - [PATCH] boot_delay should only affect output

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 for Android: free password hash cracker in your pocket

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

Date:	Tue, 13 Nov 2012 14:50:56 +0800
From:	Andrew Cooks <acooks@...il.com>
To:	Randy Dunlap <rdunlap@...otime.net>
Cc:	Andrew Cooks <acooks@...il.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org> (commit_signer:31/49=63%),
	Kay Sievers <kay@...y.org> (commit_signer:27/49=55%),
	Peter Zijlstra <a.p.zijlstra@...llo.nl> (commit_signer:7/49=14%),
	Andrew Morton <akpm@...ux-foundation.org> (commit_signer:5/49=10%),
	Ingo Molnar <mingo@...e.hu> (commit_signer:5/49=10%),
	linux-kernel@...r.kernel.org (open list)
Subject: [PATCH] boot_delay should only affect output

The boot_delay parameter affects all printk(), even if the log level
 prevents visible output from the call. It results in delays greater
 than the user intended without purpose.

This patch changes the behaviour of boot_delay to only delay output.

Signed-off-by: Andrew Cooks <acooks@...il.com>
---
 kernel/printk.c |   40 +++++++++++++++++++++-------------------
 1 files changed, 21 insertions(+), 19 deletions(-)

diff --git a/kernel/printk.c b/kernel/printk.c
index 66a2ea3..c098003 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -741,6 +741,21 @@ void __init setup_log_buf(int early)
 		free, (free * 100) / __LOG_BUF_LEN);
 }
 
+static bool __read_mostly ignore_loglevel;
+
+static int __init ignore_loglevel_setup(char *str)
+{
+	ignore_loglevel = 1;
+	printk(KERN_INFO "debug: ignoring loglevel setting.\n");
+
+	return 0;
+}
+
+early_param("ignore_loglevel", ignore_loglevel_setup);
+module_param(ignore_loglevel, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(ignore_loglevel, "ignore loglevel setting, to"
+	"print all kernel messages to the console.");
+
 #ifdef CONFIG_BOOT_PRINTK_DELAY
 
 static int boot_delay; /* msecs delay after each printk during bootup */
@@ -764,13 +779,15 @@ static int __init boot_delay_setup(char *str)
 }
 __setup("boot_delay=", boot_delay_setup);
 
-static void boot_delay_msec(void)
+static void boot_delay_msec(int level)
 {
 	unsigned long long k;
 	unsigned long timeout;
 
-	if (boot_delay == 0 || system_state != SYSTEM_BOOTING)
+	if ((boot_delay == 0 || system_state != SYSTEM_BOOTING)
+		|| (level >= console_loglevel && !ignore_loglevel)) {
 		return;
+	}
 
 	k = (unsigned long long)loops_per_msec * boot_delay;
 
@@ -789,7 +806,7 @@ static void boot_delay_msec(void)
 	}
 }
 #else
-static inline void boot_delay_msec(void)
+static inline void boot_delay_msec(int level)
 {
 }
 #endif
@@ -1232,21 +1249,6 @@ SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
 	return do_syslog(type, buf, len, SYSLOG_FROM_CALL);
 }
 
-static bool __read_mostly ignore_loglevel;
-
-static int __init ignore_loglevel_setup(char *str)
-{
-	ignore_loglevel = 1;
-	printk(KERN_INFO "debug: ignoring loglevel setting.\n");
-
-	return 0;
-}
-
-early_param("ignore_loglevel", ignore_loglevel_setup);
-module_param(ignore_loglevel, bool, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(ignore_loglevel, "ignore loglevel setting, to"
-	"print all kernel messages to the console.");
-
 /*
  * Call the console drivers, asking them to write out
  * log_buf[start] to log_buf[end - 1].
@@ -1492,7 +1494,7 @@ asmlinkage int vprintk_emit(int facility, int level,
 	int this_cpu;
 	int printed_len = 0;
 
-	boot_delay_msec();
+	boot_delay_msec(level);
 	printk_delay();
 
 	/* This stops the holder of console_sem just where we want him */
-- 
1.7.1

--
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/