[PATCH] printk: Fix unnecessary returning broken pipe error from devkmsg_read

[zhe.he]

From: He Zhe <zhe...@windriver.com>

When users read the buffer from start, there is no need to return -EPIPE
since the possible overflows will not affect the output.

Signed-off-by: He Zhe <zhe...@windriver.com>
---
 kernel/printk/printk.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 1888f6a..4a6a129 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -886,7 +886,9 @@ static ssize_t devkmsg_read(struct file *file, char __user 
*buf,
                logbuf_lock_irq();
        }
 
-       if (user->seq < log_first_seq) {
+       if (user->seq == 0) {
+               user->seq = log_first_seq;
+       } else if (user->seq < log_first_seq) {
                /* our last seen message is gone, return error and reset */
                user->idx = log_first_idx;
                user->seq = log_first_seq;
-- 
2.7.4