+++ This bug was initially created as a clone of Bug #1420434 +++

In the course of multiplexing development, it was found that the trash translator would crash if more than one instance was present in a single brick process.  Accordingly, trash was disabled so other work could continue.  The crashes look like this.

#0  0x00007f1740887ee2 in trash_dir_lookup_cbk (frame=0x7f16f017a5d0, 
    cookie=0x7f16f017b190, this=0x7f171c002320, op_ret=-1, op_errno=2, 
    inode=0x0, buf=0x7f1706ffb300, xdata=0x0, postparent=0x7f1706ffb290)
    at trash.c:680
#1  0x00007f17410b68ee in posix_lookup (frame=0x7f16f017b190, 
    this=0x7f171c001020, loc=0x7f1706ffb480, xdata=0x0) at posix.c:257
#2  0x00007f1740888723 in create_or_rename_trash_directory (
    this=0x7f171c002320) at trash.c:750
#3  0x00007f1740897561 in reconfigure (this=0x7f171c002320, 
    options=0x7f16f015e080) at trash.c:2286

The problem is that the order of reconfigure vs. notify(CHILD_UP) is different with multiplexing, and only the notify path was allocating priv->trash_itable.  Moving that to the translator's init seems to fix the problem, so trash can be reenabled.  Patch as soon as I have the bug number.

--- Additional comment from Worker Ant on 2017-02-08 10:57:38 EST ---

REVIEW: https://review.gluster.org/16567 (trash: fix problem with trash feature under multiplexing) posted (#1) for review on master by Jeff Darcy (jdarcy)

--- Additional comment from Worker Ant on 2017-02-09 08:46:49 EST ---

COMMIT: https://review.gluster.org/16567 committed in master by Shyamsundar Ranganathan (srangana) 
------
commit 1e4f9c58a1b013f3f27d515d72d1e76e1a53436e
Author: Jeff Darcy <jdarcy>
Date:   Wed Feb 8 10:48:55 2017 -0500

    trash: fix problem with trash feature under multiplexing
    
    With multiplexing, the trash translator gets a reconfigure call before
    a notify(CHILD_UP).  In this case, priv->trash_itable was not yet
    initialized, so the reconfigure would get a SEGV.  Moving the itable
    allocation to init seems to fix it, so trash can be reenabled.
    
    Change-Id: I21ac2d7fc66bac1bc4ec70fbc8bae306d73ac565
    BUG: 1420434
    Signed-off-by: Jeff Darcy <jdarcy>
    Reviewed-on: https://review.gluster.org/16567
    Smoke: Gluster Build System <jenkins.org>
    NetBSD-regression: NetBSD Build System <jenkins.org>
    CentOS-regression: Gluster Build System <jenkins.org>
    Reviewed-by: Anoop C S <anoopcs>
    Reviewed-by: jiffin tony Thottan <jthottan>
    Reviewed-by: Shyamsundar Ranganathan <srangana>