Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755197AbaGUNEM (ORCPT ); Mon, 21 Jul 2014 09:04:12 -0400 Received: from mail-ie0-f178.google.com ([209.85.223.178]:40782 "EHLO mail-ie0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753118AbaGUNCk (ORCPT ); Mon, 21 Jul 2014 09:02:40 -0400 From: Alex Elder To: akpm@linux-foundation.org Cc: kay@vrfy.org, pmladek@suse.cz, bp@suse.de, john.stultz@linaro.org, jack@suse.cz, linux-kernel@vger.kernel.org Subject: [PATCH v5 2/7] printk: insert newline for truncated records Date: Mon, 21 Jul 2014 08:02:36 -0500 Message-Id: <1405947761-26004-3-git-send-email-elder@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1405947761-26004-1-git-send-email-elder@linaro.org> References: <1405947761-26004-1-git-send-email-elder@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If a log record has LOG_PREFIX set, its predecessor record should be terminated if it was marked LOG_CONT. In devkmsg_read(), this condition was being ignored, which would lead to such records showing up combined when reading /dev/kmsg. Fix this oversight. We should similarly insert a newline in msg_print_text() in this case, to avoid formatted records getting merged. Suggested-by: Petr Mládek Signed-off-by: Alex Elder --- kernel/printk/printk.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index ffc9928..9f11eab 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -575,6 +575,7 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf, char cont = '-'; size_t len; ssize_t ret; + bool insert_newline; if (!user) return -EBADF; @@ -625,7 +626,10 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf, ((user->prev & LOG_CONT) && !(msg->flags & LOG_PREFIX))) cont = '+'; - len = sprintf(user->buf, "%u,%llu,%llu,%c;", + /* Insert a newline if the previous line was not terminated properly */ + insert_newline = (user->prev & LOG_CONT) && (msg->flags & LOG_PREFIX); + len = sprintf(user->buf, "%s%u,%llu,%llu,%c;", + insert_newline ? "\n" : "", (msg->facility << 3) | msg->level, user->seq, ts_usec, cont); user->prev = msg->flags; @@ -1013,6 +1017,12 @@ static size_t msg_print_text(const struct printk_log *msg, enum log_flags prev, newline = false; } + if ((prev & LOG_CONT) && (msg->flags & LOG_PREFIX) && len < size) { + if (buf) + buf[len++] = '\n'; + else + len++; + } do { const char *next = memchr(text, '\n', text_size); size_t text_len; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/