This bug has been copied from bug #670373 and has been proposed
to be backported to 5.6 z-stream (EUS).
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.
Technical note added. If any revisions are required, please edit the "Technical Notes" field
accordingly. All revisions will be proofread by the Engineering Content Services team.
Prior to this update, kernel panic occurred in the kfree() due to a race condition in the acpi_bus_receive_event() function. The acpi_bus_receive_event() function left the acpi_bus_event_list list attribute unlocked between checking it whether it was empty and calling the kfree() function on it. With this update, a check was added after the lock has been lifted in order to prevent the race and the calling of the kfree() function on an empty list.