Commit 3cae85f5 authored by Florian Fainelli's avatar Florian Fainelli Committed by Jonathan Corbet
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Documentation/admin-guide: kernel-parameters: Update nohlt section 



Update the documentation regarding "nohlt" and indicate that it is not
only for bugs, but can be useful to disable the architecture specific
sleep instructions. ARM, ARM64, SuperH and Microblaze all use
CONFIG_GENERIC_IDLE_POLL_SETUP which takes care of honoring the
"hlt"/"nohlt" parameters.

Signed-off-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Acked-by: default avatarRandy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210209172349.2249596-1-f.fainelli@gmail.com


Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent a15cb2c1

Documentation/admin-guide/kernel-parameters.txt

+8 −3
Original line number Diff line number Diff line
@@ -3266,9 +3266,14 @@ 
			parameter, xsave area per process might occupy more

			memory on xsaves enabled systems.



	nohlt		[BUGS=ARM,SH] Tells the kernel that the sleep(SH) or

			wfi(ARM) instruction doesn't work correctly and not to

			use it. This is also useful when using JTAG debugger.

	nohlt		[ARM,ARM64,MICROBLAZE,SH] Forces the kernel to busy wait

			in do_idle() and not use the arch_cpu_idle()

			implementation; requires CONFIG_GENERIC_IDLE_POLL_SETUP

			to be effective. This is useful on platforms where the

			sleep(SH) or wfi(ARM,ARM64) instructions do not work

			correctly or when doing power measurements to evalute

			the impact of the sleep instructions. This is also

			useful when using JTAG debugger.



	no_file_caps	Tells the kernel not to honor file capabilities.  The

			only way then for a file to be executed with privilege