From f87a304c8b3d6b4bfe2e4c7e763ae65a65209312 Mon Sep 17 00:00:00 2001 From: Hans Petter Selasky Date: Fri, 5 Aug 2016 08:58:00 +0000 Subject: [PATCH] Keep a reference count on USB keyboard polling to allow recursive cngrab() during a panic for example, similar to what the AT-keyboard driver is doing. Found by: Bruce Evans MFC after: 1 week --- sys/dev/usb/input/ukbd.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/sys/dev/usb/input/ukbd.c b/sys/dev/usb/input/ukbd.c index 02a6ff37e8d..42d96cfa64d 100644 --- a/sys/dev/usb/input/ukbd.c +++ b/sys/dev/usb/input/ukbd.c @@ -198,6 +198,7 @@ struct ukbd_softc { int sc_mode; /* input mode (K_XLATE,K_RAW,K_CODE) */ int sc_state; /* shift/lock key state */ int sc_accents; /* accent key index (> 0) */ + int sc_polling; /* polling recursion count */ int sc_led_size; int sc_kbd_size; @@ -1983,7 +1984,16 @@ ukbd_poll(keyboard_t *kbd, int on) struct ukbd_softc *sc = kbd->kb_data; UKBD_LOCK(); - if (on) { + /* + * Keep a reference count on polling to allow recursive + * cngrab() during a panic for example. + */ + if (on) + sc->sc_polling++; + else + sc->sc_polling--; + + if (sc->sc_polling != 0) { sc->sc_flags |= UKBD_FLAG_POLLING; sc->sc_poll_thread = curthread; } else {