Revision 9ca52ed979b6b45ae480a5fc56d593efb3bf16e8 authored by James Hogan on 16 October 2012, 09:16:14 UTC, committed by James Hogan on 02 March 2013, 20:09:53 UTC
Commit cc2383ec06be093789469852e1fe96e1148e9a2c ("mm: introduce
arch-specific vma flag VM_ARCH_1") merged in v3.7-rc1.

The above commit combined several arch-specific vma flags into one, and
in the process it changed the VM_GROWSUP definition to depend on
specific architectures rather than CONFIG_STACK_GROWSUP. Therefore add
an ifdef for CONFIG_METAG to also set VM_GROWSUP.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-mm@kvack.org
1 parent 1e57372
Raw File
mmc-dev-parts.txt
SD and MMC Device Partitions
============================

Device partitions are additional logical block devices present on the
SD/MMC device.

As of this writing, MMC boot partitions as supported and exposed as
/dev/mmcblkXboot0 and /dev/mmcblkXboot1, where X is the index of the
parent /dev/mmcblkX.

MMC Boot Partitions
===================

Read and write access is provided to the two MMC boot partitions. Due to
the sensitive nature of the boot partition contents, which often store
a bootloader or bootloader configuration tables crucial to booting the
platform, write access is disabled by default to reduce the chance of
accidental bricking.

To enable write access to /dev/mmcblkXbootY, disable the forced read-only
access with:

echo 0 > /sys/block/mmcblkXbootY/force_ro

To re-enable read-only access:

echo 1 > /sys/block/mmcblkXbootY/force_ro

The boot partitions can also be locked read only until the next power on,
with:

echo 1 > /sys/block/mmcblkXbootY/ro_lock_until_next_power_on

This is a feature of the card and not of the kernel. If the card does
not support boot partition locking, the file will not exist. If the
feature has been disabled on the card, the file will be read-only.

The boot partitions can also be locked permanently, but this feature is
not accessible through sysfs in order to avoid accidental or malicious
bricking.
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