Bug 1769727

Summary:	kexec fast reboot as a Technology Preview
Product:	Red Hat Enterprise Linux 8	Reporter:	Bhupesh Sharma <bhsharma>
Component:	doc-Release_Notes-8-en-US	Assignee:	Lucie Vařáková <lmanasko>
Status:	CLOSED CURRENTRELEASE	QA Contact:	RHEL DPM <rhel-docs>
Severity:	high	Docs Contact:	Sujata Kurup <skurup>
Priority:	high
Version:	8.1	CC:	bhe, bhsharma, dyoung, jklech, kdump-bugs, lkuprova, lmanasko, rhel-docs, ruyang, skurup, xiawu
Target Milestone:	rc	Keywords:	Documentation, TechPreview
Target Release:	8.0	Flags:	skurup: needinfo+ skurup: needinfo+
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Technology Preview
Doc Text:	.The `kexec` fast reboot feature is available as a Technology Preview The `kexec` fast reboot feature continues to be available as a Technology Preview. The `kexec` fast reboot significantly speeds the boot process as you can boot directly into the second kernel without passing through the Basic Input/Output System (BIOS) or firmware first. To use this feature: . Load the `kexec` kernel manually. . Reboot for changes to take effect. Note that the `kexec` fast reboot capability is available with a limited scope of support on RHEL 9 and later releases.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-01-06 11:34:01 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Bhupesh Sharma 2019-11-07 10:13:22 UTC

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:

Comment 2 Baoquan He 2019-11-21 06:41:04 UTC

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