Messages in this thread | | | Date | Thu, 14 Jun 2007 17:22:34 +0200 | From | Paolo Ornati <> | Subject | Re: /dev/loop* devices not appearing in /dev (at least since 2.6.22-rc3*) |
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On Thu, 14 Jun 2007 16:10:44 +0200 Matthew <jackdachef@gmail.com> 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 [ 457.607575] loop: the max_loop option is obsolete and will be 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 majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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