mirror of https://github.com/openzfs/zfs.git
018f26041d
There is a lock order inversion deadlock between `spa_errlog_lock` and `dp_config_rwlock`: A thread in `spa_delete_dataset_errlog()` is running from a sync task. It is holding the `dp_config_rwlock` for writer (see `dsl_sync_task_sync()`), and waiting for the `spa_errlog_lock`. A thread in `dsl_pool_config_enter()` is holding the `spa_errlog_lock` (see `spa_get_errlog_size()`) and waiting for the `dp_config_rwlock` (as reader). Note that this was introduced by #12812. This commit address this by defining the lock ordering to be dp_config_rwlock first, then spa_errlog_lock / spa_errlist_lock. spa_get_errlog() and spa_get_errlog_size() can acquire the locks in this order, and then process_error_block() and get_head_and_birth_txg() can verify that the dp_config_rwlock is already held. Additionally, a buffer overrun in `spa_get_errlog()` is corrected. Many code paths didn't check if `*count` got to zero, instead continuing to overwrite past the beginning of the userspace buffer at `uaddr`. Tested by having some errors in the pool (via `zinject -t data /path/to/file`), one thread running `zpool iostat 0.001`, and another thread runs `zfs destroy` (in a loop, although it hits the first time). This reproduces the problem easily without the fix, and works with the fix. Reviewed-by: Mark Maybee <mark.maybee@delphix.com> Reviewed-by: George Amanakis <gamanakis@gmail.com> Reviewed-by: George Wilson <gwilson@delphix.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Matthew Ahrens <mahrens@delphix.com> Closes #14239 Closes #14289 |
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| .. | ||
| os | ||
| sys | ||
| .gitignore | ||
| Makefile.am | ||
| cityhash.h | ||
| libnvpair.h | ||
| libuutil.h | ||
| libuutil_common.h | ||
| libuutil_impl.h | ||
| libzfs.h | ||
| libzfs_core.h | ||
| libzfsbootenv.h | ||
| libzutil.h | ||
| thread_pool.h | ||
| zfeature_common.h | ||
| zfs_comutil.h | ||
| zfs_deleg.h | ||
| zfs_fletcher.h | ||
| zfs_namecheck.h | ||
| zfs_prop.h | ||