git: kernel - Change default kern.ipc.shm_allow_removed=1

Matthew Dillon dillon at
Tue May 30 12:15:52 PDT 2017

commit 1e1a926738b4e738a38d810ce11252031b1062ab
Author: Matthew Dillon <dillon at>
Date:   Tue May 30 12:13:41 2017 -0700

    kernel - Change default kern.ipc.shm_allow_removed=1
    * Change kern.ipc.shm_allow_removed to default to enabled.  This feature
      allows a shared memory segment to be located by its shmid after being
      deleted, as long as some prior reference to the segment is still active.
    * Primarily used by chrome these days, this trick is convenient in that
      it allows applications to attach shared memory segments in a manner that
      do ensures they are deleted if the application is killed or seg-faults

Summary of changes:
 sys/kern/sysv_shm.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

DragonFly BSD source repository

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