If libblkid does not contain ZFS support, then 'zpool import' will scan
all block devices in /dev/ to determine which ones are components of a
ZFS filesystem. It does this by opening all the devices and stat'ing
them to determine which ones are block devices. If the device turns
out not to be a block device it is skipped.
Usually, this whole process is pretty harmless (although slow). But
there are certain devices in /dev/ which must be handled in a very
specific way or your system may crash. For example, if /dev/watchdog
is simply opened the watchdog timer will be started and your system
will panic when the timer expires.
It turns out the /dev/hpet causes similiar problems although only when
accessed under a virtual machine. For some reason accessing /dev/hpet
causes qemu to crash. To address this issue this commit adds /dev/hpet
to the device blacklist, it will be skipped solely based on its name.
(strncmp(name, "vcs", 3) == 0) ||
(strncmp(name, "parport", 7) == 0) ||
(strncmp(name, "lp", 2) == 0) ||
- (strncmp(name, "fd", 2) == 0))
+ (strncmp(name, "fd", 2) == 0) ||
+ (strncmp(name, "hpet", 4) == 0))
continue;
if ((fd = openat64(dfd, name, O_RDONLY)) < 0)