mounting a loopback file from a link fails with busybox 1.2.1

[Rob Landley]

On Monday 07 August 2006 2:26 pm, Yann Le Doaré wrote:
> Hi, I have a problem with busybox 1.2.1 (1.0.1 relase is OK for that) :
> When I want to mount a lookback file from a link, I have the "Block
> device required" error.

Sigh.  Darn it.  It's using lstat() instead of stat.  Why was I doing that...? 
In case of a dead symlink, which is treated as a file not found.  But that's 
probably the behavior we _want_, so...

Try svn 15788?
http://busybox.net/downloads/patches/svn-15788.patch

> ./busybox mount /tmp/testfslnk /mnt/floppy/ -o loop

You don't need to say "-o loop" anymore, that's treated as a NOP by the 
current busybox mount command.  It'll autodetect when it needs to do a 
loopback mount (or a bind mount for that matter).  This bug is a case of the 
autodetect code failing.

Rob

P.S.  Sigh, I'm now ~65 messages behind on the list, blocked untangling 
the "add CIFS and shared subtree support to mount" patch Vladimir Dronnikov 
sent me off-list, which is hard because the shared subtree part is something 
I want a CONFIG_NITPICK option for, but it turns out that the config 
infrastructure we lifted from the linux kernel switches off everything that 
depends on a symbol that is switched off.  It doesn't revert invisible 
symbols to their default value, it switches them _OFF_, and there's no 
obvious way to control visibility independently of selection...

And _this_ is why you shouldn't send one patch that does two things.  The 
shared subtree support is trivial compared to CIFS support, but CIFS is 
blocked on shared subtree because they were submitted as one patch...

Rob
-- 
Never bet against the cheap plastic solution.