Merge ../linus

[linux-drm-fsl-dcu.git] / Documentation / filesystems / tmpfs.txt

diff --git a/Documentation/filesystems/tmpfs.txt b/Documentation/filesystems/tmpfs.txt
index 8a155418c705eac2a05d37ce7f20d2b0696c4a1d..6dd050878a2087269b9891f704177dc7f1dc1462 100644 (file)
--- a/Documentation/filesystems/tmpfs.txt
+++ b/Documentation/filesystems/tmpfs.txt
@@ -39,7 +39,7 @@ tmpfs has the following uses:
        tmpfs   /dev/shm        tmpfs   defaults        0 0
 
    Remember to create the directory that you intend to mount tmpfs on
-   if necessary (/dev/shm is automagically created if you use devfs).
+   if necessary.
 
    This mount is _not_ needed for SYSV shared memory. The internal
    mount is used for that. (In the 2.3 kernel versions it was
@@ -63,7 +63,7 @@ size:      The limit of allocated bytes for this tmpfs instance. The
 nr_blocks: The same as size, but in blocks of PAGE_CACHE_SIZE.
 nr_inodes: The maximum number of inodes for this instance. The default
            is half of the number of your physical RAM pages, or (on a
-           a machine with highmem) the number of lowmem RAM pages,
+           machine with highmem) the number of lowmem RAM pages,
            whichever is the lower.
 
 These parameters accept a suffix k, m or g for kilo, mega and giga and
@@ -92,6 +92,15 @@ NodeList format is a comma-separated list of decimal numbers and ranges,
 a range being two hyphen-separated decimal numbers, the smallest and
 largest node numbers in the range.  For example, mpol=bind:0-3,5,7,9-15
 
+Note that trying to mount a tmpfs with an mpol option will fail if the
+running kernel does not support NUMA; and will fail if its nodelist
+specifies a node >= MAX_NUMNODES.  If your system relies on that tmpfs
+being mounted, but from time to time runs a kernel built without NUMA
+capability (perhaps a safe recovery kernel), or configured to support
+fewer nodes, then it is advisable to omit the mpol option from automatic
+mount options.  It can be added later, when the tmpfs is already mounted
+on MountPoint, by 'mount -o remount,mpol=Policy:NodeList MountPoint'.
+
 
 To specify the initial root directory you can use the following mount
 options: