From: Chris Ball <cjb@laptop.org>
To: NamJae Jeon <linkinjeon@gmail.com>
Cc: Linus Walleij <linus.ml.walleij@gmail.com>,
linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: RFC : mmc : boot partition is set as a read-write.
Date: Sun, 18 Sep 2011 23:32:46 -0400 [thread overview]
Message-ID: <m2vcsp2om9.fsf@bob.laptop.org> (raw)
In-Reply-To: <CAKYAXd8xd3sCi0CCOH6Y3AR2J2iuDQispCnt0D2mksiAWr=rgw@mail.gmail.com> (NamJae Jeon's message of "Mon, 19 Sep 2011 12:10:28 +0900")
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@laptop.org> <http://printf.net/>
One Laptop Per Child
next prev parent reply other threads:[~2011-09-19 3:32 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-19 3:10 RFC : mmc : boot partition is set as a read-write NamJae Jeon
2011-09-19 3:32 ` Chris Ball [this message]
2011-09-19 3:56 ` NamJae Jeon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=m2vcsp2om9.fsf@bob.laptop.org \
--to=cjb@laptop.org \
--cc=linkinjeon@gmail.com \
--cc=linus.ml.walleij@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mmc@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox