[Aboriginal] mdadm issue, including qemu images.

[Rob Landley]

On 03/16/2012 05:33 PM, Piotr Karbowski wrote:
> Attached two qemu images, one contain bootloader (extlinux), initramfs
> (better-initramfs v0.5 + your strace binary) and kernel and another is
> empty raid1 array with one device set as missing, without any filesystem
> on it, you can run it via:
> 
> qemu-kvm -hda better-initramfs-boot.qcow2 -hdb small-raid1.qcow2
> 
> If you wish to test it more, you can grab better-initramfs from
> github.com/slashbeast/better-initramfs, it should be failry easy to use,
> before 'make image' you can place whatever you want in sourceroot/ dir,
> then replace output/initramfs.cpio.gz with the one inside
> better-initramfs-boot.qcow2 and you should be good.


mknod("/dev/.tmp.md.785:8:17", S_IFBLK|0600, makedev(8, 17,)) = 0
open("/dev/.tmp.md.785:8:17", O_RDWR|O_EXCL|O_DIRECT|O_LARGEFILE) = 6
ioctl(6, BLKPG, 0xbfd22f88) = -1 EINVAL

Last line repeated bunches of times.

According to linux/blkpg.h BLKPG is some random constant (_IO(0x1s,105))
and then the argument is:

struct blkpg_ioctl_arg {
  int op;
  int flags;
  int datalen;
  void *data;
};

And then it gets complicated.  Since strace isn't dumping the associated
structure argument, so I need to rebuild the command and stick printf()
calls into it to dump out the structure contents.

Where do I get mdadm and is there anything to building it other than
./configure; make; make install?

Rob