isdn: avoid calling tty_ldisc_flush() in atomic context

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.

Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 6 deletions

diff --git a/drivers/isdn/i4l/isdn_tty.c b/drivers/isdn/i4l/isdn_tty.c
index fc8454d2eea5..51dc60da333b 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)))) {