xref: /linux/Documentation/ABI/testing/sysfs-memory-page-offline (revision a1c613ae4c322ddd58d5a8539dbfba2a0380a8c0)
1facb6011SAndi KleenWhat:		/sys/devices/system/memory/soft_offline_page
2facb6011SAndi KleenDate:		Sep 2009
3facb6011SAndi KleenKernelVersion:	2.6.33
4facb6011SAndi KleenContact:	andi@firstfloor.org
5facb6011SAndi KleenDescription:
6facb6011SAndi Kleen		Soft-offline the memory page containing the physical address
7facb6011SAndi Kleen		written into this file. Input is a hex number specifying the
8facb6011SAndi Kleen		physical address of the page. The kernel will then attempt
9facb6011SAndi Kleen		to soft-offline it, by moving the contents elsewhere or
10facb6011SAndi Kleen		dropping it if possible. The kernel will then be placed
11facb6011SAndi Kleen		on the bad page list and never be reused.
12facb6011SAndi Kleen
13*d0366880SRandy Dunlap		The offlining is done in kernel specific granularity.
14facb6011SAndi Kleen		Normally it's the base page size of the kernel, but
15facb6011SAndi Kleen		this might change.
16facb6011SAndi Kleen
17facb6011SAndi Kleen		The page must be still accessible, not poisoned. The
18facb6011SAndi Kleen		kernel will never kill anything for this, but rather
19facb6011SAndi Kleen		fail the offline.  Return value is the size of the
20facb6011SAndi Kleen		number, or a error when the offlining failed.  Reading
21facb6011SAndi Kleen		the file is not allowed.
22facb6011SAndi Kleen
23facb6011SAndi KleenWhat:		/sys/devices/system/memory/hard_offline_page
24facb6011SAndi KleenDate:		Sep 2009
25facb6011SAndi KleenKernelVersion:	2.6.33
26facb6011SAndi KleenContact:	andi@firstfloor.org
27facb6011SAndi KleenDescription:
28facb6011SAndi Kleen		Hard-offline the memory page containing the physical
29facb6011SAndi Kleen		address written into this file. Input is a hex number
30facb6011SAndi Kleen		specifying the physical address of the page. The
31facb6011SAndi Kleen		kernel will then attempt to hard-offline the page, by
32facb6011SAndi Kleen		trying to drop the page or killing any owner or
33facb6011SAndi Kleen		triggering IO errors if needed.  Note this may kill
34facb6011SAndi Kleen		any processes owning the page. The kernel will avoid
35facb6011SAndi Kleen		to access this page assuming it's poisoned by the
36facb6011SAndi Kleen		hardware.
37facb6011SAndi Kleen
38*d0366880SRandy Dunlap		The offlining is done in kernel specific granularity.
39facb6011SAndi Kleen		Normally it's the base page size of the kernel, but
40facb6011SAndi Kleen		this might change.
41facb6011SAndi Kleen
42facb6011SAndi Kleen		Return value is the size of the number, or a error when
43facb6011SAndi Kleen		the offlining failed.
44facb6011SAndi Kleen		Reading the file is not allowed.
45