Re: passing params to boot readonly

[Hans Reiser <reiser@namesys.com>]

Ryan Cumming wrote:

>On December 12, 2001 21:50, Stewart Allen wrote:
>
>>I'm in a bit of a pickle and need to find a way to pass boot params to a
>>reiserfs rootfs to *prevent* it from replaying the journal on single-user
>>boot. This may seem like a strange request, but I've got a degraded RAID
>>array that I need to poke around in before deciding whether or not to send
>>a disk off to a rehab lab. If the replay occurs, it will potentially
>>destroy the fs since I'm using a degraded snapshot of the failed disk in
>>hopes of reclaiming *some* of my data. The system is running 2.2.x (can't
>>remember and can't find out w/out booting).
>>
>>Do I have a snowball's chance of pulling this off?
>>
>
>Well, kinda. The only thing that can deter ReiserFS from replaying the 
>journal is convincing it that the physical media it's on is actually read 
>only. Some quick less/grep work revealed that there is no option that makes 
>the SCSI subsystem claim its devices are readonly (although it'd be extremely 
>useful for situations such as this).
>
>It'd probably be pretty easy to make a boot disk using a hacked version of 
>ReiserFS that refuses to replay the journal, by adding a "return 0;" near the 
>top of journal_read(struct super_block *) in journal.c. However, you might 
>feel more comfortable sending it off for data recovery than testing kernel 
>hacks on it ;)
>
>-Ryan
>-
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>
why not just edit the source code directly and recompile?  

Hans