On Thu, May 10, 2007 at 11:39:49AM +0400, Alexey Dobriyan wrote:
> On Wed, May 09, 2007 at 05:20:59PM -0700, Jeremy Fitzhardinge wrote:
> > 100% reliable, but a bit obscure. I'm booting an FC6 livecd with a
> > paravirt_ops kernel under Xen. The relevant part of the iso's initrd
> > script is:
> >
> > + mknod /dev/loop118 b 7 118
> > + mknod /dev/loop119 b 7 119
> > + mknod /dev/loop120 b 7 120
> > + mknod /dev/loop121 b 7 121
> > + mkdir -p /dev/mapper
> > + mknod /dev/mapper/control c 10 63
> > + modprobe loop max_loop=128
> > loop: the max_loop option is obsolete and will be removed in March 2008
> > loop: module loaded
> > + modprobe dm_snapshot
> > device-mapper: ioctl: 4.11.0-ioctl (2006-10-12) initialised: [email protected]
> > + '[' 0 == 1 ']'
> > + losetup /dev/loop120 /sysroot/squashfs.img
> > ------------[ cut here ]------------
> > kernel BUG at /home/jeremy/hg/xen/paravirt/linux/include/linux/module.h:396!
> > invalid opcode: 0000 [#1]
> > PREEMPT SMP
> > Modules linked in: dm_snapshot dm_mod loop
> > CPU: 0
> > EIP: 0061:[<d085a911>] Not tainted VLI
> > EFLAGS: 00010246 (2.6.21-paravirt #1339)
> > [...]
>
> This must be caused by dynamic loop devices creation patch
>
> Steps to reproduce:
>
> mknod foo b 7 1
> losetup foo 1.img
>
> where "7 1" is major/minor pair which doesn't created by udev et al
> after module loading.
I don't understand what "+ 1" is doing in lo_open(). Off by one?
It's removal would certainly fix creation of random number of loop
devices after just "losetup -a".
Also refcount of loop module can be made negative via
mknod foo b 7 42
losetup -d foo # sic
-
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/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
