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Maxim Sobolev
a127039dd0
flush_pagedep_deps() drops the soft updates lock to obtain the vnode of a new directory. If its MKDIR_BODY dependency completes in that window, the lookup of the directory's first block in flush_newblk_dep() can find a stale allocindir left behind by a previous owner of the same block, relocated by ffs_reallocblks() and freed, and panic. The test grows interleaved files past UFS_NDADDR to keep clusters being relocated, while other workers create subdirectories in a parent with IN_ENDOFF set, so that ffs_vput_pair() syncs it, and fsync() them to complete the mkdir dependencies. The file system layout and the way the writers put their blocks on disk are arranged so that a new directory takes over a freed block whose dependency is still retained; the details are in the script. With dtrace=1, the test also counts how often this precondition is met, which works on a fixed kernel too. PR: 297976 Reviewed by: kib, pho Tested by: pho Sponsored by: Sippy Software, Inc. Differential revision: https://reviews.freebsd.org/D59356
This directory tree contains tools used for the maintenance and testing of FreeBSD. There is no toplevel Makefile structure since these tools are not meant to be built as part of the standard system, though there may be individual Makefiles in some of the subdirs. Please read the README files in the subdirs for further information.