aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/initrd.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/initrd.txt')
-rw-r--r--Documentation/initrd.txt24
1 files changed, 8 insertions, 16 deletions
diff --git a/Documentation/initrd.txt b/Documentation/initrd.txt
index 7de1c80cd719..b1b6440237a6 100644
--- a/Documentation/initrd.txt
+++ b/Documentation/initrd.txt
@@ -67,8 +67,7 @@ initrd adds the following new options:
67 as the last process has closed it, all data is freed and /dev/initrd 67 as the last process has closed it, all data is freed and /dev/initrd
68 can't be opened anymore. 68 can't be opened anymore.
69 69
70 root=/dev/ram0 (without devfs) 70 root=/dev/ram0
71 root=/dev/rd/0 (with devfs)
72 71
73 initrd is mounted as root, and the normal boot procedure is followed, 72 initrd is mounted as root, and the normal boot procedure is followed,
74 with the RAM disk still mounted as root. 73 with the RAM disk still mounted as root.
@@ -90,8 +89,7 @@ you're building an install floppy), the root file system creation
90procedure should create the /initrd directory. 89procedure should create the /initrd directory.
91 90
92If initrd will not be mounted in some cases, its content is still 91If initrd will not be mounted in some cases, its content is still
93accessible if the following device has been created (note that this 92accessible if the following device has been created:
94does not work if using devfs):
95 93
96# mknod /dev/initrd b 1 250 94# mknod /dev/initrd b 1 250
97# chmod 400 /dev/initrd 95# chmod 400 /dev/initrd
@@ -119,8 +117,7 @@ We'll describe the loopback device method:
119 (if space is critical, you may want to use the Minix FS instead of Ext2) 117 (if space is critical, you may want to use the Minix FS instead of Ext2)
120 3) mount the file system, e.g. 118 3) mount the file system, e.g.
121 # mount -t ext2 -o loop initrd /mnt 119 # mount -t ext2 -o loop initrd /mnt
122 4) create the console device (not necessary if using devfs, but it can't 120 4) create the console device:
123 hurt to do it anyway):
124 # mkdir /mnt/dev 121 # mkdir /mnt/dev
125 # mknod /mnt/dev/console c 5 1 122 # mknod /mnt/dev/console c 5 1
126 5) copy all the files that are needed to properly use the initrd 123 5) copy all the files that are needed to properly use the initrd
@@ -152,12 +149,7 @@ have to be given:
152 149
153 root=/dev/ram0 init=/linuxrc rw 150 root=/dev/ram0 init=/linuxrc rw
154 151
155if not using devfs, or 152(rw is only necessary if writing to the initrd file system.)
156
157 root=/dev/rd/0 init=/linuxrc rw
158
159if using devfs. (rw is only necessary if writing to the initrd file
160system.)
161 153
162With LOADLIN, you simply execute 154With LOADLIN, you simply execute
163 155
@@ -217,9 +209,9 @@ following command:
217# exec chroot . what-follows <dev/console >dev/console 2>&1 209# exec chroot . what-follows <dev/console >dev/console 2>&1
218 210
219Where what-follows is a program under the new root, e.g. /sbin/init 211Where what-follows is a program under the new root, e.g. /sbin/init
220If the new root file system will be used with devfs and has no valid 212If the new root file system will be used with udev and has no valid
221/dev directory, devfs must be mounted before invoking chroot in order to 213/dev directory, udev must be initialized before invoking chroot in order
222provide /dev/console. 214to provide /dev/console.
223 215
224Note: implementation details of pivot_root may change with time. In order 216Note: implementation details of pivot_root may change with time. In order
225to ensure compatibility, the following points should be observed: 217to ensure compatibility, the following points should be observed:
@@ -236,7 +228,7 @@ Now, the initrd can be unmounted and the memory allocated by the RAM
236disk can be freed: 228disk can be freed:
237 229
238# umount /initrd 230# umount /initrd
239# blockdev --flushbufs /dev/ram0 # /dev/rd/0 if using devfs 231# blockdev --flushbufs /dev/ram0
240 232
241It is also possible to use initrd with an NFS-mounted root, see the 233It is also possible to use initrd with an NFS-mounted root, see the
242pivot_root(8) man page for details. 234pivot_root(8) man page for details.