---
- branch: MAIN
  date: Sun Sep 26 21:29:39 UTC 2021
  files:
  - new: '1.124'
    old: '1.123'
    path: src/sys/kern/kern_event.c
    pathrev: src/sys/kern/kern_event.c@1.124
    type: modified
  - new: '1.53'
    old: '1.52'
    path: src/sys/kern/vfs_init.c
    pathrev: src/sys/kern/vfs_init.c@1.53
    type: modified
  - new: '1.553'
    old: '1.552'
    path: src/sys/kern/vfs_syscalls.c
    pathrev: src/sys/kern/vfs_syscalls.c@1.553
    type: modified
  - new: '1.43'
    old: '1.42'
    path: src/sys/sys/event.h
    pathrev: src/sys/sys/event.h@1.43
    type: modified
  id: 20210926T212939Z.03bb89ceda6f88fa2752d6d91d6383091e43701e
  log: |
    Fix the locking around EVFILT_FS.  Previously, the code would walk the
    fs_klist and take the kqueue_misc_lock inside the event callback.
    However, that list can be modified by the attach and detach callbacks,
    which could result in the walker stepping right off a cliff.

    Instead, we give the fs_klist it's own lock, and hold it while we
    call knote(), using the NOTE_SUBMIT protocol.  Also, fs_filtops
    into vfs_syscalls.c so all of the locking logic is contained in one
    file (there is precedence with sig_filtops).  fs_filtops is now marked
    MPSAFE.
  module: src
  subject: 'CVS commit: src/sys'
  unixtime: '1632691779'
  user: thorpej