LSI Adapters using the Megaraid_sas driver may hang during boot or an adapter reset

In very limited cases, a system configured to boot through an LSI SAS adapter may hang on boot; it may also hang during an adapter reset command. This is caused by the megaraid_sas driver disabling interrupts and failing to re-enable them. This latent bug, discovered during Red Hat partner testing on an LSI SAS 9285CV-8e, can also occur on other cards using the megaraid_sas driver. Since the timing window for this bug is very small, rebooting the system should result in a successful boot. In the case of a hang during an adapter reset command, a module unload/load should resolve the issue.

The issue is fixed in a Red Hat Enterprise Linux 6.5 (RHEL6.5) kernel errata (kernel-2.6.32-431.17.1) due to ship in early May 2014; it will also be fixed in RHEL6.6 and in RHEL7. The fix is also included a RHEL6.4 errata (kernel-2.6.32-358.39.1) that shipped on 22 April 2014 but that errata is only available to Premium RHEL Subscription customers and to Standard RHEL subscription customers with Extended Update Support (EUS) subscriptions.

Customers with Standard RHEL subscriptions who do not have access to the EUS stream and who are not satisfied with the workaround of rebooting the system in the case of a boot failure or a module unload/load in the case of a failure during module reset MUST MOVE to the RHEL6.5 errata containing the fix or to RHEL6.6.