diff options
Diffstat (limited to 'sys/kern/subr_bus.c')
-rw-r--r-- | sys/kern/subr_bus.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c index 420834a..89876d227 100644 --- a/sys/kern/subr_bus.c +++ b/sys/kern/subr_bus.c @@ -1220,13 +1220,16 @@ devclass_get_count(devclass_t dc) * @brief Get the maximum unit number used in a devclass * * Note that this is one greater than the highest currently-allocated - * unit. + * unit. If a null devclass_t is passed in, -1 is returned to indicate + * that not even the devclass has been allocated yet. * * @param dc the devclass to examine */ int devclass_get_maxunit(devclass_t dc) { + if (dc == NULL) + return (-1); return (dc->maxunit); } |