linux-ext4 - minix/ext2 + rd problem

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Date:	Tue, 14 Oct 2008 16:43:55 +0200 (CEST)
From:	Richard Kojedzinszky <krichy@...etwork.hu>
To:	npiggin@...e.de, linux-ext4@...r.kernel.org
Subject: minix/ext2 + rd problem

dear all,

I got an embedded system, where I use ramdisk, minix on it as a filesystem 
for /etc. With kernels 2.4 and with 2.6.19 kernels also, the following 
code did exactly what i wanted, creating an image of the /etc without 
unmounting it:

# mount -o remount,ro /etc
# cat /dev/ram0 > /tmp/image
# mount -o remount,rw /etc

And then I had a consistent image from /etc in /tmp/image.

This worked still with kernel version 2.6.23.14, but nowadays i upgraded 
to 2.6.26.2, and noticed that the little code didnt work anymore. I wrote 
a simple test script for checking, and reproducing the issue, which is 
also attached. Unfortunately this does not work with ext2 also.

my linux version is:
Linux version 2.6.26 (root@...chy.tvnetwork.hu) (gcc version 4.2.4 (Debian 
4.2.4-3)) #27 SMP PREEMPT Tue Oct 14 15:19:30 CEST 2008

i use debian lenny/sid.

Were there any intended change that made this behaviour change or was it 
by an accident?

Thanks in advance,

Kojedzinszky Richard
TvNetWork Nyrt.
E-mail: krichy (at) tvnetwork [dot] hu
PGP: 0x24E79141
   Fingerprint = 6847 ECFF EF58 0C09 18A5  16CF 270F 0C6F 24E7 9141
Download attachment "test2.sh" of type "APPLICATION/x-sh" (435 bytes)

View attachment "ver_linux.txt" of type "TEXT/plain" (1207 bytes)

View attachment ".config" of type "TEXT/PLAIN" (47589 bytes)