VMware has published a patch for ESXi 5.5
The ESXi Installable has also been replaced with ESXi 5.5 Update 3a (ESXi 5.5 Update 3 is gone):
This patch updates the esx-base VIB to resolve an issue where snapshot consolidation or deletion results in the virtual machines running on VMware ESXi 5.5 Update 3 hosts to fail with the error: Unexpected signal: 11. You will see an log message similar to the following in the vmware.log file:
[YYYY-MM-DD] Z| vcpu-0| I120: SNAPSHOT: SnapshotDiskTreeFind: Detected node change from 'scsiX:X' to ''.
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