lkml.org 
[lkml]   [2019]   [Mar]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.19 38/68] tun: fix blocking read
Date
4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Timur Celik <mail@timurcelik.de>

[ Upstream commit 71828b2240692cec0e68b8d867bc00e1745e7fae ]

This patch moves setting of the current state into the loop. Otherwise
the task may end up in a busy wait loop if none of the break conditions
are met.

Signed-off-by: Timur Celik <mail@timurcelik.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/tun.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -2122,9 +2122,9 @@ static void *tun_ring_recv(struct tun_fi
}

add_wait_queue(&tfile->wq.wait, &wait);
- current->state = TASK_INTERRUPTIBLE;

while (1) {
+ set_current_state(TASK_INTERRUPTIBLE);
ptr = ptr_ring_consume(&tfile->tx_ring);
if (ptr)
break;
@@ -2140,7 +2140,7 @@ static void *tun_ring_recv(struct tun_fi
schedule();
}

- current->state = TASK_RUNNING;
+ set_current_state(TASK_RUNNING);
remove_wait_queue(&tfile->wq.wait, &wait);

out:

\
 
 \ /
  Last update: 2019-03-08 14:03    [W:0.235 / U:1.400 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site