Re: CVS commit: src/sys/kern

[Thor Lancelot Simon <tls%rek.tjls.com@localhost>]

On Wed, Sep 24, 2008 at 07:38:20PM +0700, Robert Elz wrote:
>     Date:        Wed, 24 Sep 2008 10:07:19 +0000 (UTC)
>     From:        Andrew Doran <ad%NetBSD.org@localhost>
>     Message-ID:  <20080924100719.D78AE175D0%cvs.netbsd.org@localhost>
> 
>   | Prevent r/w to r/o downgrade until such time as someone has verified all
>   | the relevant file system code.
> 
> Please don't do that - I do rw -> ro "down"grades (I'd call it an upgrade...)
> all the time.   As long as you know what's up (that is, to make sure there
> is no possibility of stale data) it is fine, and causes no problems.

This also breaks products which run from flash with their filesystems mounted
read-only most of the time, but remount them read-write in order to write
back configuration data when it changes.  That is not an uncommon model
AFAIK and it poses a fairly major problem for me.

If anyone can give me an idea what actually has to be verified, I can (since
I have to) put considerable time into it.

Thor