mirror of https://github.com/openzfs/zfs.git
0fdd6106bb
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 |
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| .. | ||
| os | ||
| sys | ||
| .gitignore | ||
| Makefile.am | ||
| libnvpair.h | ||
| libuutil.h | ||
| libuutil_common.h | ||
| libuutil_impl.h | ||
| libzfs.h | ||
| libzfs_core.h | ||
| libzfs_impl.h | ||
| libzutil.h | ||
| thread_pool.h | ||
| zfeature_common.h | ||
| zfs_comutil.h | ||
| zfs_deleg.h | ||
| zfs_fletcher.h | ||
| zfs_namecheck.h | ||
| zfs_prop.h | ||