From 6514406b988d9947fa6422072b22a0eb90610fbf Mon Sep 17 00:00:00 2001 From: rwatson Date: Thu, 3 Feb 2005 10:35:05 +0000 Subject: When entering siocnputc() with (kdb_active), don't acquire (or release) the sio spin mutex, as use of synchronization primitives in the debugger can result in substantial problems. With this patch in place entering the debugger via a serial console is made substantially more reliable. MFC after: 1 week Tested by: kris Discussed with: bde --- sys/dev/sio/sio.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'sys/dev/sio') diff --git a/sys/dev/sio/sio.c b/sys/dev/sio/sio.c index ca59986..65b1029 100644 --- a/sys/dev/sio/sio.c +++ b/sys/dev/sio/sio.c @@ -2583,16 +2583,20 @@ siocnputc(struct consdev *cd, int c) } s = spltty(); need_unlock = 0; - if (sio_inited == 2 && !mtx_owned(&sio_lock)) { - mtx_lock_spin(&sio_lock); - need_unlock = 1; + if (!kdb_active) { + if (sio_inited == 2 && !mtx_owned(&sio_lock)) { + mtx_lock_spin(&sio_lock); + need_unlock = 1; + } } siocnopen(&sp, iobase, speed); siocntxwait(iobase); outb(iobase + com_data, c); siocnclose(&sp, iobase); - if (need_unlock) - mtx_unlock_spin(&sio_lock); + if (!kdb_active) { + if (need_unlock) + mtx_unlock_spin(&sio_lock); + } splx(s); } -- cgit v1.1