Re: RFC : mmc : boot partition is set as a read-write.
From: Chris Ball
Date: Sun Sep 18 2011 - 23:32:55 EST
Hi,
On Sun, Sep 18 2011, NamJae Jeon wrote:
> mmc : boot partition is set as a read-write.
>
> There is a case that user directly update boot partition through mmcblk0boot0,1.
> However, the current boot partition is set as a read-only.
> I suggest that boot partition is set as a read-write if there is no
> reason that it should be read-only.
There is a reason.
Documentation/mmc/mmc-dev-parts.txt:
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
==
- Chris.
--
Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/>
One Laptop Per Child
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