Sophos Anti-Virus on-access scanner causing unexpected restarts on OS X Mavericks

  • Article ID: 120822
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  • 3 customers rated this article 1.3 out of 6
  • Updated: 14 Oct 2014


Following an unexpected restart the following message appears:

First seen in

Sophos Anti-Virus for Mac OS X

Operating systems
Mac OS X 10.9.x

The issue is caused by a race condition causing a time out.

What To Do

The issue is related to that detailed in Apple kb TS4646.

To determine whether you are affected by this issue access the panic log produced by the unexpected restart.  The log will contain an entry similar to the following:

panic(cpu 2 caller 0xffffff80047da9b0): "vnode_rele_ext: vp 0xffffff802e81bd20 usecount -ve : -1. v_tag = 16, v_type = 1, v_flag = 184800."@/SourceCache/xnu/xnu-2422.1.72/bsd/vfs/vfs_subr.c:1788

Where the specific references confirming the issue are "vnode_rele_ext" and "usecount -ve".

If you see these references this issue is fixed in the following versions of Sophos Anti-Virus for Mac OS X:


See article 120189 for the release dates calendar detailing when these versions are available.

Note: Only Sophos Anti-Virus version 9.x is supported on OS X Mavericks. If you are running version 8.x this will need to be upgraded to version 9.

If you need more information or guidance, then please contact technical support.

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