-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 On 12/03/2014 03:24 AM, Goffredo Baroncelli wrote: > I am thinking about that. Today the device discovery happens: a) > when a device appears, two udev rules run "btrfs dev scan > <device>" > > /lib/udev/rules.d/70-btrfs.rules > /lib/udev/rules.d/80-btrfs-lvm.rules > > b) during the boot it is ran a "btrfs device scan", which scan all > the device (this happens in debian for other distros may be > different) > > c) after a btrfs.mkfs, which starts a device scan on each devices > of the new filesystem > > d) by the user
Are you sure the kernel only gains awareness of btrfs volumes when user space runs btrfs device scan? If that is so then that means you can not boot from a multi device btrfs root without using an initramfs. I thought the kernel auto scanned all devices if you tried to mount a multi device volume, but if this is so, then yes, the udev rules could be fixed to not call btrfs device scan on an lvm snapshot. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBCgAGBQJUf9BpAAoJENRVrw2cjl5RgcQIALCGfplK/xgX/QaiRjNW96l2 DWNPQMIhPesci0gF7Th3sNboew0hrc3g6S0a55wAO12CBhMPdzHxHjd9iFVpKi9O vzvU36XyzwdcPJkBqRdPJMT2kX+428gYUW7jkyC8usj5eSCyeiIodJuxirGDL5Nb 3TttEJOpbPHGlTzHjAqEcK2ybzYi9HCN3CD3fuLagP9n+4zmFE7tGaGglZ9+7P58 wZjlP5xKDCR4Cu5Hr+5ErrmT2EoOvFC+PLKOT8xXhD9Y2emk2AtuY+5l/w7I+SIS 42gTUqPOx/8AOxBhOhkI0pPO8eK7S/lP1LKoXF0WWHhX8CgJLIHwj5KniDYcjBA= =HI90 -----END PGP SIGNATURE----- -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html