Technical white paper UEFI Secure Boot on HP business notebooks, desktops, and workstations

The Preinstall should set the Secure Boot/Boot Mode policy to Enable and Legacy, and to Disable for Windows 8 64/32.

Table 3. Policy settings and OS supported (notebooks only)
Boot Mode/ Secure Boot

Disable

Enable

 

 

 

LegacyLegacy OS: XP, Vista, Windows 7, LinuxInvalid

 

 

 

UEFI Hybrid

Legacy OS: XP, Vista, Windows 7, Linux

Invalid

 

 

 

 

Linux, Windows 8 with Native UEFI but

 

UEFI Nativeno Secure BootWindows 8

 

 

 

If the OS and the BIOS policies have a mismatch, the system may fail to boot.

Note

Having Secure Boot enabled with UEFI Hybrid or Legacy selected is an invalid state. The BIOS will ignore any request for this change.

The user can use BIOS Setup (F10) to Enable/Disable Secure Boot or it can be changed remotely using the WMI interface, which uses WMI scripts, or by using HP’s BIOSConfig utility.

When Secure Boot “Disable” command is sent from WMI to BIOS, the status of the Secure Boot doesn’t change immediately. At next reboot, the physical presence must be checked to prevent malicious software attacks.

To complete the process, the customer or technician is required to type in a random four-digit verification code that is displayed in the message generated by the BIOS.

Operating System Boot Mode Change

A change to the operating system Secure Boot mode is pending. Please enter the pass code displayed below to complete the change. If you did not initiate this request, press the ESC key to continue without accepting the pending change.

Operating System Boot Mode Change (021)XXXX+ ENTER - to complete the change ESC – continue without changingFor more information, please visit: www.hp.com/go/techcenter/startup

Firmware boot policy for desktops and workstations

The settings for the Secure Boot policy on desktop and workstations use the following rules:

Secure Boot set to “Enabled” forces Legacy Support to “Disabled.”Legacy Support set to “Disabled” forces:The CSM to be disabledAll Legacy Boot Sources in the Boot Order to be disabledAll “Legacy-only” Option ROM Launch Policies to be changed to “UEFI-only”

You can manage these settings using BIOS Setup (F10), WMI (which uses WMI scripts), or HP’s BIOSConfig Utility.

When the Secure Boot “Disable” command is sent programmatically (via WMI or HP’s BIOS Config Utility), the state of Secure Boot and its dependent settings don’t change immediately. During the next reboot, the physical presence must be checked to prevent malicious software attacks.

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