freebsd-nq/module
ilbsmart 779a6c0bf6 deadlock between mm_sem and tx assign in zfs_write() and page fault
The bug time sequence:
1. thread #1, `zfs_write` assign a txg "n".
2. In a same process, thread #2, mmap page fault (which means the
   `mm_sem` is hold) occurred, `zfs_dirty_inode` open a txg failed,
   and wait previous txg "n" completed.
3. thread #1 call `uiomove` to write, however page fault is occurred
   in `uiomove`, which means it need `mm_sem`, but `mm_sem` is hold by
   thread #2, so it stuck and can't complete,  then txg "n" will
   not complete.

So thread #1 and thread #2 are deadlocked.

Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Grady Wong <grady.w@xtaotech.com>
Closes #7939
2018-10-16 11:11:24 -07:00
..
avl Update build system and packaging 2018-05-29 16:00:33 -07:00
icp Fedora 28: Fix misc bounds check compiler warnings 2018-08-26 12:55:44 -07:00
lua Update build system and packaging 2018-05-29 16:00:33 -07:00
nvpair Add new fnvlist_lookup_* functions 2018-10-03 15:30:55 -07:00
spl Create /proc/sys/kernel/spl/gitrev with git hash 2018-10-08 21:57:02 -07:00
unicode Update build system and packaging 2018-05-29 16:00:33 -07:00
zcommon deadlock between mm_sem and tx assign in zfs_write() and page fault 2018-10-16 11:11:24 -07:00
zfs deadlock between mm_sem and tx assign in zfs_write() and page fault 2018-10-16 11:11:24 -07:00
.gitignore Prepare SPL repo to merge with ZFS repo 2018-05-29 14:51:39 -07:00
Makefile.in Update build system and packaging 2018-05-29 16:00:33 -07:00