From: John Ogness <john.ogness@linutronix.de>
To: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Thomas Gleixner <tglx@linutronix.de>,
linux-kernel@vger.kernel.org
Subject: [PATCH next v4 07/15] printk: introduce CONSOLE_LOG_MAX
Date: Wed, 3 Mar 2021 11:15:20 +0100 [thread overview]
Message-ID: <20210303101528.29901-8-john.ogness@linutronix.de> (raw)
In-Reply-To: <20210303101528.29901-1-john.ogness@linutronix.de>
Instead of using "LOG_LINE_MAX + PREFIX_MAX" for temporary buffer
sizes, introduce CONSOLE_LOG_MAX. This represents the maximum size
that is allowed to be printed to the console for a single record.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
---
kernel/printk/printk.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 9a5f9ccc46ea..2c8873fa2f29 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -410,7 +410,12 @@ static u64 clear_seq;
#else
#define PREFIX_MAX 32
#endif
-#define LOG_LINE_MAX (1024 - PREFIX_MAX)
+
+/* the maximum size of a formatted record (i.e. with prefix added per line) */
+#define CONSOLE_LOG_MAX 1024
+
+/* the maximum size allowed to be reserved for a record */
+#define LOG_LINE_MAX (CONSOLE_LOG_MAX - PREFIX_MAX)
#define LOG_LEVEL(v) ((v) & 0x07)
#define LOG_FACILITY(v) ((v) >> 3 & 0xff)
@@ -1472,11 +1477,11 @@ static int syslog_print(char __user *buf, int size)
char *text;
int len = 0;
- text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+ text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
if (!text)
return -ENOMEM;
- prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+ prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
while (size > 0) {
size_t n;
@@ -1542,7 +1547,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
u64 seq;
bool time;
- text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+ text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
if (!text)
return -ENOMEM;
@@ -1554,7 +1559,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
*/
seq = find_first_fitting_seq(clear_seq, -1, size, true, time);
- prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+ prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
len = 0;
prb_for_each_record(seq, prb, seq, &r) {
@@ -2187,8 +2192,7 @@ EXPORT_SYMBOL(printk);
#else /* CONFIG_PRINTK */
-#define LOG_LINE_MAX 0
-#define PREFIX_MAX 0
+#define CONSOLE_LOG_MAX 0
#define printk_time false
#define prb_read_valid(rb, seq, r) false
@@ -2506,7 +2510,7 @@ static inline int can_use_console(void)
void console_unlock(void)
{
static char ext_text[CONSOLE_EXT_LOG_MAX];
- static char text[LOG_LINE_MAX + PREFIX_MAX];
+ static char text[CONSOLE_LOG_MAX];
unsigned long flags;
bool do_cond_resched, retry;
struct printk_info info;
--
2.20.1
next prev parent reply other threads:[~2021-03-03 14:21 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-03 10:15 [PATCH next v4 00/15] printk: remove logbuf_lock John Ogness
2021-03-03 10:15 ` [PATCH next v4 01/15] um: synchronize kmsg_dumper John Ogness
2021-03-03 10:15 ` [PATCH next v4 02/15] mtd: mtdoops: " John Ogness
2021-03-11 9:50 ` Miquel Raynal
2021-03-03 10:15 ` [PATCH next v4 03/15] printk: limit second loop of syslog_print_all John Ogness
2021-03-03 10:15 ` [PATCH next v4 04/15] printk: kmsg_dump: remove unused fields John Ogness
2021-03-03 10:15 ` [PATCH next v4 05/15] printk: refactor kmsg_dump_get_buffer() John Ogness
2021-03-03 10:15 ` [PATCH next v4 06/15] printk: consolidate kmsg_dump_get_buffer/syslog_print_all code John Ogness
2021-03-03 10:15 ` John Ogness [this message]
2021-03-03 13:35 ` [PATCH next v4 07/15] printk: introduce CONSOLE_LOG_MAX Petr Mladek
2021-03-03 10:15 ` [PATCH next v4 08/15] printk: use seqcount_latch for clear_seq John Ogness
2021-03-03 10:15 ` [PATCH next v4 09/15] printk: use atomic64_t for devkmsg_user.seq John Ogness
2021-03-03 10:15 ` [PATCH next v4 10/15] printk: add syslog_lock John Ogness
2021-03-03 10:15 ` [PATCH next v4 11/15] printk: kmsg_dumper: remove @active field John Ogness
2021-03-03 10:15 ` [PATCH next v4 12/15] printk: introduce a kmsg_dump iterator John Ogness
2021-03-03 13:48 ` Petr Mladek
2021-03-03 10:15 ` [PATCH next v4 13/15] printk: remove logbuf_lock John Ogness
2021-03-03 10:15 ` [PATCH next v4 14/15] printk: kmsg_dump: remove _nolock() variants John Ogness
2021-03-03 10:15 ` [PATCH next v4 15/15] printk: console: remove unnecessary safe buffer usage John Ogness
2021-03-03 13:18 ` lkml delivery: was: Re: [PATCH next v4 00/15] printk: remove logbuf_lock Petr Mladek
2021-03-03 14:34 ` Steven Rostedt
2021-03-03 15:34 ` Petr Mladek
2021-03-08 15:09 ` Petr Mladek
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