mISDN: Fix wrong usage of flush_work_sync while holding locks

It is a bad idea to hold a spinlock and call flush_work_sync.
Move the workqueue cleanup outside the spinlock and use cancel_work_sync,
on closing the channel this seems to be the more correct function.
Remove the never used and constant return value of mISDN_freebchannel.

Signed-off-by: Karsten Keil <keil@b1-systems.de>
Cc: <stable@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 5 deletions

diff --git a/drivers/isdn/mISDN/hwchannel.c b/drivers/isdn/mISDN/hwchannel.c
index ef34fd40867c..2602be23f341 100644
--- a/drivers/isdn/mISDN/hwchannel.c
+++ b/drivers/isdn/mISDN/hwchannel.c
@@ -148,17 +148,16 @@ mISDN_clear_bchannel(struct bchannel *ch)
 	ch->next_minlen = ch->init_minlen;
 	ch->maxlen = ch->init_maxlen;
 	ch->next_maxlen = ch->init_maxlen;
+	skb_queue_purge(&ch->rqueue);
+	ch->rcount = 0;
 }
 EXPORT_SYMBOL(mISDN_clear_bchannel);
 
-int
+void
 mISDN_freebchannel(struct bchannel *ch)
 {
+	cancel_work_sync(&ch->workq);
 	mISDN_clear_bchannel(ch);
-	skb_queue_purge(&ch->rqueue);
-	ch->rcount = 0;
-	flush_work_sync(&ch->workq);
-	return 0;
 }
 EXPORT_SYMBOL(mISDN_freebchannel);