Updated sg3_utils packages that fix one bug are now available for Red Hat Enterprise Linux 6.
The sg3_utils packages contain a collection of tools for SCSI devices that use the Linux SCSI generic (sg) interface. This collection includes utilities for database copying based on "dd" syntax and semantics (the "sg_dd", "sgp_dd" and "sgm_dd" commands), INQUIRY data checking and associated pages ("sg_inq"), mode and log page checking ("sg_modes" and "sg_logs"), disk spinning ("sg_start") and self-tests ("sg_senddiag"), as well as other utilities. It also contains the rescan-scsi-bus.sh script.
The logic used in the show_devices() function (as used by the "sginfo" command) to identify the available storage devices opened these devices by scanning the /dev directory. Consequently, the /dev/snapshot file was opened, causing the system to prepare for suspend/hibernate and, as a part of that, to block hot-added CPUs from being activated. To fix this bug, the logic used in the show_devices() function to decide, which devices to open, has been adjusted. As a result, running the "sginfo -l" command no longer has the unintended side effect of blocking the activation of hot-added CPUs.
Users of sg3_utils are advised to upgrade to these updated packages, which fix this bug.