From 5c53d819c71c63fdc91f30a59164583f68e2d63a Mon Sep 17 00:00:00 2001 From: liu chuansheng Date: Fri, 6 Jul 2012 09:50:08 -0700 Subject: [PATCH 1/7] printk: replacing the raw_spin_lock/unlock with raw_spin_lock/unlock_irq In function devkmsg_read/writev/llseek/poll/open()..., the function raw_spin_lock/unlock is used, there is potential deadlock case happening. CPU1: thread1 doing the cat /dev/kmsg: raw_spin_lock(&logbuf_lock); while (user->seq == log_next_seq) { when thread1 run here, at this time one interrupt is coming on CPU1 and running based on this thread,if the interrupt handle called the printk which need the logbuf_lock spin also, it will cause deadlock. So we should use raw_spin_lock/unlock_irq here. Acked-by: Kay Sievers Signed-off-by: liu chuansheng Signed-off-by: Greg Kroah-Hartman --- kernel/printk.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/kernel/printk.c b/kernel/printk.c index dba18211685e..12886cd19cd9 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -430,20 +430,20 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf, ret = mutex_lock_interruptible(&user->lock); if (ret) return ret; - raw_spin_lock(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); while (user->seq == log_next_seq) { if (file->f_flags & O_NONBLOCK) { ret = -EAGAIN; - raw_spin_unlock(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); goto out; } - raw_spin_unlock(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); ret = wait_event_interruptible(log_wait, user->seq != log_next_seq); if (ret) goto out; - raw_spin_lock(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); } if (user->seq < log_first_seq) { @@ -451,7 +451,7 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf, user->idx = log_first_idx; user->seq = log_first_seq; ret = -EPIPE; - raw_spin_unlock(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); goto out; } @@ -501,7 +501,7 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf, user->idx = log_next(user->idx); user->seq++; - raw_spin_unlock(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); if (len > count) { ret = -EINVAL; @@ -528,7 +528,7 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence) if (offset) return -ESPIPE; - raw_spin_lock(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); switch (whence) { case SEEK_SET: /* the first record */ @@ -552,7 +552,7 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence) default: ret = -EINVAL; } - raw_spin_unlock(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); return ret; } @@ -566,14 +566,14 @@ static unsigned int devkmsg_poll(struct file *file, poll_table *wait) poll_wait(file, &log_wait, wait); - raw_spin_lock(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); if (user->seq < log_next_seq) { /* return error when data has vanished underneath us */ if (user->seq < log_first_seq) ret = POLLIN|POLLRDNORM|POLLERR|POLLPRI; ret = POLLIN|POLLRDNORM; } - raw_spin_unlock(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); return ret; } @@ -597,10 +597,10 @@ static int devkmsg_open(struct inode *inode, struct file *file) mutex_init(&user->lock); - raw_spin_lock(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); user->idx = log_first_idx; user->seq = log_first_seq; - raw_spin_unlock(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); file->private_data = user; return 0; From e3f5a5f27153228569f3396049838e9727dae86e Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Fri, 6 Jul 2012 09:50:09 -0700 Subject: [PATCH 2/7] kmsg: escape the backslash character while exporting data Non-printable characters in the log data are hex-escaped to ensure safe post processing. We need to escape a backslash we find in the data, to be able to distinguish it from a backslash we add for the escaping. Also escape the non-printable character 127. Thanks to Miloslav Trmac for the heads up. Reported-by: Michael Neuling Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- kernel/printk.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/printk.c b/kernel/printk.c index 12886cd19cd9..505863aa3a7f 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -465,7 +465,7 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf, for (i = 0; i < msg->text_len; i++) { unsigned char c = log_text(msg)[i]; - if (c < ' ' || c >= 128) + if (c < ' ' || c >= 127 || c == '\\') len += sprintf(user->buf + len, "\\x%02x", c); else user->buf[len++] = c; @@ -489,7 +489,7 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf, continue; } - if (c < ' ' || c >= 128) { + if (c < ' ' || c >= 127 || c == '\\') { len += sprintf(user->buf + len, "\\x%02x", c); continue; } From 43a73a50b352cd3df25b3ced72033942a6a0f919 Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Fri, 6 Jul 2012 09:50:09 -0700 Subject: [PATCH 3/7] kmsg: add the facility number to the syslog prefix After the recent split of facility and level into separate variables, we miss the facility value (always 0 for kernel-originated messages) in the syslog prefix. On Tue, Jul 3, 2012 at 12:45 PM, Dan Carpenter wrote: > Static checkers complain about the impossible condition here. > > In 084681d14e ('printk: flush continuation lines immediately to > console'), we changed msg->level from being a u16 to being an unsigned > 3 bit bitfield. Cc: Dan Carpenter Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- kernel/printk.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/kernel/printk.c b/kernel/printk.c index 505863aa3a7f..37cde752cb8a 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -818,15 +818,18 @@ static size_t print_time(u64 ts, char *buf) static size_t print_prefix(const struct log *msg, bool syslog, char *buf) { size_t len = 0; + unsigned int prefix = (msg->facility << 3) | msg->level; if (syslog) { if (buf) { - len += sprintf(buf, "<%u>", msg->level); + len += sprintf(buf, "<%u>", prefix); } else { len += 3; - if (msg->level > 9) - len++; - if (msg->level > 99) + if (prefix > 999) + len += 3; + else if (prefix > 99) + len += 2; + else if (prefix > 9) len++; } } From cb424ffe9f45ad80267f2a98fbd9bf21caa0ce22 Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Fri, 6 Jul 2012 09:50:09 -0700 Subject: [PATCH 4/7] kmsg: properly handle concurrent non-blocking read() from /proc/kmsg The /proc/kmsg read() interface is internally simply wired up to a sequence of syslog() syscalls, which might are racy between their checks and actions, regarding concurrency. In the (very uncommon) case of concurrent readers of /dev/kmsg, relying on usual O_NONBLOCK behavior, the recently introduced mutex might block an O_NONBLOCK reader in read(), when poll() returns for it, but another process has already read the data in the meantime. We've seen that while running artificial test setups and tools that "fight" about /proc/kmsg data. This restores the original /proc/kmsg behavior, where in case of concurrent read()s, poll() might wake up but the read() syscall will just return 0 to the caller, while another process has "stolen" the data. This is in the general case not the expected behavior, but it is the exact same one, that can easily be triggered with a 3.4 kernel, and some tools might just rely on it. The mutex is not needed, the original integrity issue which introduced it, is in the meantime covered by: "fill buffer with more than a single message for SYSLOG_ACTION_READ" 116e90b23f74d303e8d607c7a7d54f60f14ab9f2 Cc: Yuanhan Liu Acked-by: Jan Beulich Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- kernel/printk.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/kernel/printk.c b/kernel/printk.c index 37cde752cb8a..be9a82b2f0b3 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -1021,7 +1021,6 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) { bool clear = false; static int saved_console_loglevel = -1; - static DEFINE_MUTEX(syslog_mutex); int error; error = check_syslog_permissions(type, from_file); @@ -1048,17 +1047,11 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) error = -EFAULT; goto out; } - error = mutex_lock_interruptible(&syslog_mutex); - if (error) - goto out; error = wait_event_interruptible(log_wait, syslog_seq != log_next_seq); - if (error) { - mutex_unlock(&syslog_mutex); + if (error) goto out; - } error = syslog_print(buf, len); - mutex_unlock(&syslog_mutex); break; /* Read/clear last kernel messages */ case SYSLOG_ACTION_READ_CLEAR: From 68b6507dc554ba015b5ed5e13b1ed4993cdf4024 Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Fri, 6 Jul 2012 09:50:09 -0700 Subject: [PATCH 5/7] kmsg: make sure all messages reach a newly registered boot console We suppress printing kmsg records to the console, which are already printed immediately while we have received their fragments. Newly registered boot consoles print the entire kmsg buffer during registration. Clear the console-suppress flag after we skipped the record during its first storage, so any later print will see these records as usual. Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- kernel/printk.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/printk.c b/kernel/printk.c index be9a82b2f0b3..f02f1f5ddc30 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -1953,6 +1953,12 @@ skip: */ console_idx = log_next(console_idx); console_seq++; + /* + * We will get here again when we register a new + * CON_PRINTBUFFER console. Clear the flag so we + * will properly dump everything later. + */ + msg->flags &= ~LOG_NOCONS; goto skip; } From eb02dac93708f581c99858a19162af8ca2b6bfcb Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Mon, 9 Jul 2012 10:05:10 -0700 Subject: [PATCH 6/7] kmsg: /proc/kmsg - support reading of partial log records Restore support for partial reads of any size on /proc/kmsg, in case the supplied read buffer is smaller than the record size. Some people seem to think is is ia good idea to run: $ dd if=/proc/kmsg bs=1 of=... as a klog bridge. Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=44211 Reported-by: Jukka Ollila Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- kernel/printk.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/kernel/printk.c b/kernel/printk.c index f02f1f5ddc30..50c33411442d 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -217,6 +217,7 @@ static DEFINE_RAW_SPINLOCK(logbuf_lock); /* the next printk record to read by syslog(READ) or /proc/kmsg */ static u64 syslog_seq; static u32 syslog_idx; +static size_t syslog_partial; /* index and sequence number of the first record stored in the buffer */ static u64 log_first_seq; @@ -890,22 +891,33 @@ static int syslog_print(char __user *buf, int size) while (size > 0) { size_t n; + size_t skip; raw_spin_lock_irq(&logbuf_lock); if (syslog_seq < log_first_seq) { /* messages are gone, move to first one */ syslog_seq = log_first_seq; syslog_idx = log_first_idx; + syslog_partial = 0; } if (syslog_seq == log_next_seq) { raw_spin_unlock_irq(&logbuf_lock); break; } + + skip = syslog_partial; msg = log_from_idx(syslog_idx); n = msg_print_text(msg, true, text, LOG_LINE_MAX); - if (n <= size) { + if (n - syslog_partial <= size) { + /* message fits into buffer, move forward */ syslog_idx = log_next(syslog_idx); syslog_seq++; + n -= syslog_partial; + syslog_partial = 0; + } else if (!len){ + /* partial read(), remember position */ + n = size; + syslog_partial += n; } else n = 0; raw_spin_unlock_irq(&logbuf_lock); @@ -913,17 +925,15 @@ static int syslog_print(char __user *buf, int size) if (!n) break; - len += n; - size -= n; - buf += n; - n = copy_to_user(buf - n, text, n); - - if (n) { - len -= n; + if (copy_to_user(buf, text + skip, n)) { if (!len) len = -EFAULT; break; } + + len += n; + size -= n; + buf += n; } kfree(text); @@ -1107,6 +1117,7 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) /* messages are gone, move to first one */ syslog_seq = log_first_seq; syslog_idx = log_first_idx; + syslog_partial = 0; } if (from_file) { /* @@ -1129,6 +1140,7 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) idx = log_next(idx); seq++; } + error -= syslog_partial; } raw_spin_unlock_irq(&logbuf_lock); break; From 5becfb1df5ac8e491338e64b1029685ccad4b39c Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Mon, 9 Jul 2012 12:15:42 -0700 Subject: [PATCH 7/7] kmsg: merge continuation records while printing In (the unlikely) case our continuation merge buffer is busy, we unfortunately can not merge further continuation printk()s into a single record and have to store them separately, which leads to split-up output of these lines when they are printed. Add some flags about newlines and prefix existence to these records and try to reconstruct the full line again, when the separated records are printed. Reported-By: Michael Neuling Cc: Dave Jones Cc: Linus Torvalds Tested-By: Michael Neuling Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- kernel/printk.c | 120 +++++++++++++++++++++++++++++++----------------- 1 file changed, 78 insertions(+), 42 deletions(-) diff --git a/kernel/printk.c b/kernel/printk.c index 50c33411442d..177fa49357a5 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -194,8 +194,10 @@ static int console_may_schedule; */ enum log_flags { - LOG_DEFAULT = 0, - LOG_NOCONS = 1, /* already flushed, do not print to console */ + LOG_NOCONS = 1, /* already flushed, do not print to console */ + LOG_NEWLINE = 2, /* text ended with a newline */ + LOG_PREFIX = 4, /* text started with a prefix */ + LOG_CONT = 8, /* text is a fragment of a continuation line */ }; struct log { @@ -217,6 +219,7 @@ static DEFINE_RAW_SPINLOCK(logbuf_lock); /* the next printk record to read by syslog(READ) or /proc/kmsg */ static u64 syslog_seq; static u32 syslog_idx; +static enum log_flags syslog_prev; static size_t syslog_partial; /* index and sequence number of the first record stored in the buffer */ @@ -839,13 +842,26 @@ static size_t print_prefix(const struct log *msg, bool syslog, char *buf) return len; } -static size_t msg_print_text(const struct log *msg, bool syslog, - char *buf, size_t size) +static size_t msg_print_text(const struct log *msg, enum log_flags prev, + bool syslog, char *buf, size_t size) { const char *text = log_text(msg); size_t text_size = msg->text_len; + bool prefix = true; + bool newline = true; size_t len = 0; + if ((prev & LOG_CONT) && !(msg->flags & LOG_PREFIX)) + prefix = false; + + if (msg->flags & LOG_CONT) { + if ((prev & LOG_CONT) && !(prev & LOG_NEWLINE)) + prefix = false; + + if (!(msg->flags & LOG_NEWLINE)) + newline = false; + } + do { const char *next = memchr(text, '\n', text_size); size_t text_len; @@ -863,16 +879,22 @@ static size_t msg_print_text(const struct log *msg, bool syslog, text_len + 1>= size - len) break; - len += print_prefix(msg, syslog, buf + len); + if (prefix) + len += print_prefix(msg, syslog, buf + len); memcpy(buf + len, text, text_len); len += text_len; - buf[len++] = '\n'; + if (next || newline) + buf[len++] = '\n'; } else { /* SYSLOG_ACTION_* buffer size only calculation */ - len += print_prefix(msg, syslog, NULL); - len += text_len + 1; + if (prefix) + len += print_prefix(msg, syslog, NULL); + len += text_len; + if (next || newline) + len++; } + prefix = true; text = next; } while (text); @@ -898,6 +920,7 @@ static int syslog_print(char __user *buf, int size) /* messages are gone, move to first one */ syslog_seq = log_first_seq; syslog_idx = log_first_idx; + syslog_prev = 0; syslog_partial = 0; } if (syslog_seq == log_next_seq) { @@ -907,11 +930,12 @@ static int syslog_print(char __user *buf, int size) skip = syslog_partial; msg = log_from_idx(syslog_idx); - n = msg_print_text(msg, true, text, LOG_LINE_MAX); + n = msg_print_text(msg, syslog_prev, true, text, LOG_LINE_MAX); if (n - syslog_partial <= size) { /* message fits into buffer, move forward */ syslog_idx = log_next(syslog_idx); syslog_seq++; + syslog_prev = msg->flags; n -= syslog_partial; syslog_partial = 0; } else if (!len){ @@ -954,6 +978,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear) u64 next_seq; u64 seq; u32 idx; + enum log_flags prev; if (clear_seq < log_first_seq) { /* messages are gone, move to first available one */ @@ -967,10 +992,11 @@ static int syslog_print_all(char __user *buf, int size, bool clear) */ seq = clear_seq; idx = clear_idx; + prev = 0; while (seq < log_next_seq) { struct log *msg = log_from_idx(idx); - len += msg_print_text(msg, true, NULL, 0); + len += msg_print_text(msg, prev, true, NULL, 0); idx = log_next(idx); seq++; } @@ -978,10 +1004,11 @@ static int syslog_print_all(char __user *buf, int size, bool clear) /* move first record forward until length fits into the buffer */ seq = clear_seq; idx = clear_idx; + prev = 0; while (len > size && seq < log_next_seq) { struct log *msg = log_from_idx(idx); - len -= msg_print_text(msg, true, NULL, 0); + len -= msg_print_text(msg, prev, true, NULL, 0); idx = log_next(idx); seq++; } @@ -990,17 +1017,19 @@ static int syslog_print_all(char __user *buf, int size, bool clear) next_seq = log_next_seq; len = 0; + prev = 0; while (len >= 0 && seq < next_seq) { struct log *msg = log_from_idx(idx); int textlen; - textlen = msg_print_text(msg, true, text, LOG_LINE_MAX); + textlen = msg_print_text(msg, prev, true, text, LOG_LINE_MAX); if (textlen < 0) { len = textlen; break; } idx = log_next(idx); seq++; + prev = msg->flags; raw_spin_unlock_irq(&logbuf_lock); if (copy_to_user(buf + len, text, textlen)) @@ -1013,6 +1042,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear) /* messages are gone, move to next one */ seq = log_first_seq; idx = log_first_idx; + prev = 0; } } } @@ -1117,6 +1147,7 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) /* messages are gone, move to first one */ syslog_seq = log_first_seq; syslog_idx = log_first_idx; + syslog_prev = 0; syslog_partial = 0; } if (from_file) { @@ -1127,18 +1158,18 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) */ error = log_next_idx - syslog_idx; } else { - u64 seq; - u32 idx; + u64 seq = syslog_seq; + u32 idx = syslog_idx; + enum log_flags prev = syslog_prev; error = 0; - seq = syslog_seq; - idx = syslog_idx; while (seq < log_next_seq) { struct log *msg = log_from_idx(idx); - error += msg_print_text(msg, true, NULL, 0); + error += msg_print_text(msg, prev, true, NULL, 0); idx = log_next(idx); seq++; + prev = msg->flags; } error -= syslog_partial; } @@ -1408,10 +1439,9 @@ asmlinkage int vprintk_emit(int facility, int level, static char textbuf[LOG_LINE_MAX]; char *text = textbuf; size_t text_len; + enum log_flags lflags = 0; unsigned long flags; int this_cpu; - bool newline = false; - bool prefix = false; int printed_len = 0; boot_delay_msec(); @@ -1450,7 +1480,7 @@ asmlinkage int vprintk_emit(int facility, int level, recursion_bug = 0; printed_len += strlen(recursion_msg); /* emit KERN_CRIT message */ - log_store(0, 2, LOG_DEFAULT, 0, + log_store(0, 2, LOG_PREFIX|LOG_NEWLINE, 0, NULL, 0, recursion_msg, printed_len); } @@ -1463,7 +1493,7 @@ asmlinkage int vprintk_emit(int facility, int level, /* mark and strip a trailing newline */ if (text_len && text[text_len-1] == '\n') { text_len--; - newline = true; + lflags |= LOG_NEWLINE; } /* strip syslog prefix and extract log level or control flags */ @@ -1473,7 +1503,7 @@ asmlinkage int vprintk_emit(int facility, int level, if (level == -1) level = text[1] - '0'; case 'd': /* KERN_DEFAULT */ - prefix = true; + lflags |= LOG_PREFIX; case 'c': /* KERN_CONT */ text += 3; text_len -= 3; @@ -1483,22 +1513,20 @@ asmlinkage int vprintk_emit(int facility, int level, if (level == -1) level = default_message_loglevel; - if (dict) { - prefix = true; - newline = true; - } + if (dict) + lflags |= LOG_PREFIX|LOG_NEWLINE; - if (!newline) { + if (!(lflags & LOG_NEWLINE)) { /* * Flush the conflicting buffer. An earlier newline was missing, * or another task also prints continuation lines. */ - if (cont.len && (prefix || cont.owner != current)) + if (cont.len && (lflags & LOG_PREFIX || cont.owner != current)) cont_flush(); /* buffer line if possible, otherwise store it right away */ if (!cont_add(facility, level, text, text_len)) - log_store(facility, level, LOG_DEFAULT, 0, + log_store(facility, level, lflags | LOG_CONT, 0, dict, dictlen, text, text_len); } else { bool stored = false; @@ -1510,13 +1538,13 @@ asmlinkage int vprintk_emit(int facility, int level, * flush it out and store this line separately. */ if (cont.len && cont.owner == current) { - if (!prefix) + if (!(lflags & LOG_PREFIX)) stored = cont_add(facility, level, text, text_len); cont_flush(); } if (!stored) - log_store(facility, level, LOG_DEFAULT, 0, + log_store(facility, level, lflags, 0, dict, dictlen, text, text_len); } printed_len += text_len; @@ -1615,8 +1643,8 @@ static struct cont { static struct log *log_from_idx(u32 idx) { return NULL; } static u32 log_next(u32 idx) { return 0; } static void call_console_drivers(int level, const char *text, size_t len) {} -static size_t msg_print_text(const struct log *msg, bool syslog, - char *buf, size_t size) { return 0; } +static size_t msg_print_text(const struct log *msg, enum log_flags prev, + bool syslog, char *buf, size_t size) { return 0; } static size_t cont_print_text(char *text, size_t size) { return 0; } #endif /* CONFIG_PRINTK */ @@ -1892,6 +1920,7 @@ void wake_up_klogd(void) /* the next printk record to write to the console */ static u64 console_seq; static u32 console_idx; +static enum log_flags console_prev; /** * console_unlock - unlock the console system @@ -1952,6 +1981,7 @@ again: /* messages are gone, move to first one */ console_seq = log_first_seq; console_idx = log_first_idx; + console_prev = 0; } skip: if (console_seq == log_next_seq) @@ -1975,10 +2005,11 @@ skip: } level = msg->level; - len = msg_print_text(msg, false, text, sizeof(text)); - + len = msg_print_text(msg, console_prev, false, + text, sizeof(text)); console_idx = log_next(console_idx); console_seq++; + console_prev = msg->flags; raw_spin_unlock(&logbuf_lock); stop_critical_timings(); /* don't trace print latency */ @@ -2241,6 +2272,7 @@ void register_console(struct console *newcon) raw_spin_lock_irqsave(&logbuf_lock, flags); console_seq = syslog_seq; console_idx = syslog_idx; + console_prev = syslog_prev; raw_spin_unlock_irqrestore(&logbuf_lock, flags); /* * We're about to replay the log buffer. Only do this to the @@ -2534,8 +2566,7 @@ bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog, } msg = log_from_idx(dumper->cur_idx); - l = msg_print_text(msg, syslog, - line, size); + l = msg_print_text(msg, 0, syslog, line, size); dumper->cur_idx = log_next(dumper->cur_idx); dumper->cur_seq++; @@ -2575,6 +2606,7 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog, u32 idx; u64 next_seq; u32 next_idx; + enum log_flags prev; size_t l = 0; bool ret = false; @@ -2597,23 +2629,27 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog, /* calculate length of entire buffer */ seq = dumper->cur_seq; idx = dumper->cur_idx; + prev = 0; while (seq < dumper->next_seq) { struct log *msg = log_from_idx(idx); - l += msg_print_text(msg, true, NULL, 0); + l += msg_print_text(msg, prev, true, NULL, 0); idx = log_next(idx); seq++; + prev = msg->flags; } /* move first record forward until length fits into the buffer */ seq = dumper->cur_seq; idx = dumper->cur_idx; + prev = 0; while (l > size && seq < dumper->next_seq) { struct log *msg = log_from_idx(idx); - l -= msg_print_text(msg, true, NULL, 0); + l -= msg_print_text(msg, prev, true, NULL, 0); idx = log_next(idx); seq++; + prev = msg->flags; } /* last message in next interation */ @@ -2621,14 +2657,14 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog, next_idx = idx; l = 0; + prev = 0; while (seq < dumper->next_seq) { struct log *msg = log_from_idx(idx); - l += msg_print_text(msg, syslog, - buf + l, size - l); - + l += msg_print_text(msg, prev, syslog, buf + l, size - l); idx = log_next(idx); seq++; + prev = msg->flags; } dumper->next_seq = next_seq;