On Thu, 14 Jun 2007 16:10:44 +0200
Matthew <[EMAIL PROTECTED]> wrote:

> I just tried out
> 
> modprobe loop max_loop=32
> 
> output of dmesg is:
> 
> [  457.607575] loop: the max_loop option is obsolete and will be
> removed in March 2008
> [  457.607578] loop: module loaded
> 
> but there are NO loop devices in /dev:
> 
> ls -l /dev/ | grep loop
> still shows nothing, strange ...

it's not strange, with your kernel version "max_loop" will just limit
the max number of loop devices at most.

This is what happens with the mentioned patch (-rc5 and later):

+       /*
+        * loop module now has a feature to instantiate underlying device
+        * structure on-demand, provided that there is an access dev node.
+        * However, this will not work well with user space tool that doesn't
+        * know about such "feature".  In order to not break any existing
+        * tool, we do the following:
+        *
+        * (1) if max_loop is specified, create that many upfront, and this
+        *     also becomes a hard limit.
+        * (2) if max_loop is not specified, create 8 loop device on module
+        *     load, user can further extend loop device by create dev node
+        *     themselves and have kernel automatically instantiate actual
+        *     device on-demand.
+        */


So with this patch "max_loop=32" will create 32 loop devices... but
then it doesn't allow more of them.

Without options it creates 8 and you (or some userspace tool) can add
more dynamically.

-- 
        Paolo Ornati
        Linux 2.6.22-rc4-cfs-v16-g47932c49 on x86_64
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to