MFV r353558: 10572 10579 Fix race in dnode_check_slots_free()
illumos/illumos-gate@
aa02ea01948372a32cbf08bfc31c72c32e3fc81e
https://github.com/illumos/illumos-gate/commit/
aa02ea01948372a32cbf08bfc31c72c32e3fc81e
10572 Fix race in dnode_check_slots_free()
https://www.illumos.org/issues/10572
The Fix from ZoL:
Currently, dnode_check_slots_free() works by checking dn->dn_type
in the dnode to determine if the dnode is reclaimable. However,
there is a small window of time between dnode_free_sync() in the
first call to dsl_dataset_sync() and when the useraccounting code
is run when the type is set DMU_OT_NONE, but the dnode is not yet
evictable, leading to crashes. This patch adds the ability for
dnodes to track which txg they were last dirtied in and adds a
check for this before performing the reclaim.
This patch also corrects several instances when dn_dirty_link was
treated as a list_node_t when it is technically a multilist_node_t.
10579 Don't allow dnode allocation if dn_holds != 0
https://www.illumos.org/issues/10579
The fix from ZoL:
This patch simply fixes a small bug where dnode_hold_impl() could
attempt to allocate a dnode that was in the process of being freed,
but which still had active references. This patch simply adds the
required check.
Author: Tom Caputi <tcaputi@datto.com>
Reported by: delphij
MFC after: 2 weeks
X-MFC with: r353176