From a6540f731d506d9e82444cf0020e716613d4c46c Mon Sep 17 00:00:00 2001
From: Alan Cox <alan@linux.intel.com>
Date: Mon, 22 Jun 2009 18:42:29 +0100
Subject: [PATCH] ppp: Fix throttling bugs

The ppp layer goes around calling the unthrottle method from non sleeping
paths. This isn't safe because the unthrottle methods in the tty layer need
to be able to sleep (consider a USB dongle).

Until now this didn't show up because the ppp layer never actually throttled
a port so the unthrottle was always a no-op. Currently it's a mutex taking
path so warnings are spewed if the unthrottle occurs via certain paths.

Fix this by removing the unneccessary unthrottle calls.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 drivers/net/ppp_async.c   | 1 -
 drivers/net/ppp_synctty.c | 1 -
 2 files changed, 2 deletions(-)

diff --git a/drivers/net/ppp_async.c b/drivers/net/ppp_async.c
index 6de8399d6dd9..17c116bb332c 100644
--- a/drivers/net/ppp_async.c
+++ b/drivers/net/ppp_async.c
@@ -356,7 +356,6 @@ ppp_asynctty_receive(struct tty_struct *tty, const unsigned char *buf,
 	if (!skb_queue_empty(&ap->rqueue))
 		tasklet_schedule(&ap->tsk);
 	ap_put(ap);
-	tty_unthrottle(tty);
 }
 
 static void
diff --git a/drivers/net/ppp_synctty.c b/drivers/net/ppp_synctty.c
index d2fa2db13586..aa3d39f38e22 100644
--- a/drivers/net/ppp_synctty.c
+++ b/drivers/net/ppp_synctty.c
@@ -397,7 +397,6 @@ ppp_sync_receive(struct tty_struct *tty, const unsigned char *buf,
 	if (!skb_queue_empty(&ap->rqueue))
 		tasklet_schedule(&ap->tsk);
 	sp_put(ap);
-	tty_unthrottle(tty);
 }
 
 static void
-- 
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