Matthew Ahrens 0fdd6106bb dmu_objset_from_ds must be called with dp_config_rwlock held ... The normal lock order is that the dp_config_rwlock must be held before the ds_opening_lock. For example, dmu_objset_hold() does this. However, dmu_objset_open_impl() is called with the ds_opening_lock held, and if the dp_config_rwlock is not already held, it will attempt to acquire it. This may lead to deadlock, since the lock order is reversed. Looking at all the callers of dmu_objset_open_impl() (which is principally the callers of dmu_objset_from_ds()), almost all callers already have the dp_config_rwlock. However, there are a few places in the send and receive code paths that do not. For example: dsl_crypto_populate_key_nvlist, send_cb, dmu_recv_stream, receive_write_byref, redact_traverse_thread. This commit resolves the problem by requiring all callers ot dmu_objset_from_ds() to hold the dp_config_rwlock. In most cases, the code has been restructured such that we call dmu_objset_from_ds() earlier on in the send and receive processes, when we already have the dp_config_rwlock, and save the objset_t until we need it in the middle of the send or receive (similar to what we already do with the dsl_dataset_t). Thus we do not need to acquire the dp_config_rwlock in many new places. I also cleaned up code in dmu_redact_snap() and send_traverse_thread(). Reviewed-by: Paul Dagnelie <pcd@delphix.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Paul Zuchowski <pzuchowski@datto.com> Signed-off-by: Matthew Ahrens <mahrens@delphix.com> Closes #9662 Closes #10115		2020-03-12 10:55:02 -07:00
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spl	Improve performance of zio_taskq_member	2020-03-03 10:29:38 -08:00
zfs	dmu_objset_from_ds must be called with dp_config_rwlock held	2020-03-12 10:55:02 -07:00
Makefile.in	OpenZFS restructuring - move platform specific sources	2019-09-06 11:26:26 -07:00