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Document URL: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.1_release_notes/

Section Number and Name: Chapter 6. Technology Previews, Section 6.3. Kernel

Describe the issue:

kexec as a Technology Preview
-----------------------------

The kexec system call has been provided as a Technology Preview. This system call enables loading and booting into another kernel from the currently running kernel, thus performing the function of the boot loader from within the kernel. Hardware initialization, which is normally done during a standard system boot, is not performed during a kexec boot, which significantly reduces the time required for a reboot. 

kexec fast reboot as a Technology Preview
-----------------------------------------

The kexec fast reboot feature, continues to be available as a Technology Preview. kexec fast reboot makes the reboot significantly faster. To use this feature, you must load the kexec kernel manually, and then reboot the operating system. 

Suggestions for improvement: Add sections 'kexec as a Technology Preview' and 'kexec fast reboot as a Technology Preview' to the Release Notes 

Additional information:

Hi Bhupesh, Jaroslav

Talked with DaveY on IRC, he is worried that the 'kexec syscall call' saying could be misleading, to cause misunderstanding about the kexec fast reboot method to customers. Since here for kexec fast reboot, we use kexec_load/_file_load system calls to load kernel, then execute 'kexec -e' to call 'reboot' system call. People may wrongly think the kexec system call as kexec_load/_file_load. So how about we tune it as 'kexec fast reboot' directly?

Thanks
Baoquan