Subject: [PATCH 2/2] isdn: avoid calling tty_ldisc_flush() in atomic context

From: Tilman Schmidt <[email-masked]>
Date: Tue, 6 Jul 2010 02:18:27 +0200 (CEST)

Remove the call to tty_ldisc_flush() from the RESULT_NO_CARRIER
branch of isdn_tty_modem_result(), as already proposed in commit
00409bb045887ec5e7b9e351bc080c38ab6bfd33.
This avoids a "sleeping function called from invalid context" BUG
when the hardware driver calls the statcallb() callback with
command==ISDN_STAT_DHUP in atomic context, which in turn calls
isdn_tty_modem_result(RESULT_NO_CARRIER, ~), and from there,
tty_ldisc_flush() which may sleep.

Impact: bugfix
Signed-off-by: Tilman Schmidt <[email-masked]>
---
 drivers/isdn/i4l/isdn_tty.c |    6 ------
 1 files changed, 0 insertions(+), 6 deletions(-)

diff --git a/drivers/isdn/i4l/isdn_tty.c b/drivers/isdn/i4l/isdn_tty.c
index fc8454d..51dc60d 100644
--- a/drivers/isdn/i4l/isdn_tty.c
+++ b/drivers/isdn/i4l/isdn_tty.c
@@ -2636,12 +2636,6 @@ isdn_tty_modem_result(int code, modem_info * info)
 		if ((info->flags & ISDN_ASYNC_CLOSING) || (!info->tty)) {
 			return;
 		}
-#ifdef CONFIG_ISDN_AUDIO
-		if ( !info->vonline )
-			tty_ldisc_flush(info->tty);
-#else
-		tty_ldisc_flush(info->tty);
-#endif
 		if ((info->flags & ISDN_ASYNC_CHECK_CD) &&
 		    (!((info->flags & ISDN_ASYNC_CALLOUT_ACTIVE) &&
 		       (info->flags & ISDN_ASYNC_CALLOUT_NOHUP)))) {
-- 
1.6.5.3.298.g39add