Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 8fcc9bc3 authored by Baoquan He's avatar Baoquan He Committed by Ingo Molnar
Browse files

Documentation/kernel-parameters.txt: Update 'memmap=' boot option description 



In commit:

  9710f581 ("x86, mm: Let "memmap=" take more entries one time")

... 'memmap=' was changed to adopt multiple, comma delimited values in a
single entry, so update the related description.

In the special case of only specifying size value without an offset,
like memmap=nn[KMG], memmap behaves similarly to mem=nn[KMG], so update
it too here.

Furthermore, for memmap=nn[KMG]$ss[KMG], an escape character needs be added
before '$' for some bootloaders. E.g in grub2, if we specify memmap=100M$5G
as suggested by the documentation, "memmap=100MG" gets passed to the kernel.

Clarify all this.

Signed-off-by: default avatarBaoquan He <bhe@redhat.com>
Acked-by: default avatarKees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Cc: douly.fnst@cn.fujitsu.com
Cc: dyoung@redhat.com
Cc: m.mizuma@jp.fujitsu.com
Link: http://lkml.kernel.org/r/1494654390-23861-4-git-send-email-bhe@redhat.com


[ Various spelling fixes. ]
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 4cdba14f

Documentation/admin-guide/kernel-parameters.txt

+9 −0
Original line number Diff line number Diff line
@@ -2127,6 +2127,12 @@ 
	memmap=nn[KMG]@ss[KMG]

			[KNL] Force usage of a specific region of memory.

			Region of memory to be used is from ss to ss+nn.

			If @ss[KMG] is omitted, it is equivalent to mem=nn[KMG],

			which limits max address to nn[KMG].

			Multiple different regions can be specified,

			comma delimited.

			Example:

				memmap=100M@2G,100M#3G,1G!1024G



	memmap=nn[KMG]#ss[KMG]

			[KNL,ACPI] Mark specific memory as ACPI data.
@@ -2139,6 +2145,9 @@ 
			         memmap=64K$0x18690000

			         or

			         memmap=0x10000$0x18690000

			Some bootloaders may need an escape character before '$',

			like Grub2, otherwise '$' and the following number

			will be eaten.



	memmap=nn[KMG]!ss[KMG]

			[KNL,X86] Mark specific memory as protected.