Re: Who reordered my disks (probably v4.8-rc1 problem)

[james harvey]

On Sun, Aug 14, 2016 at 5:09 AM, Pavel Machek <pavel@xxxxxx> wrote:
>> Use static (persistent) naming instead, /dev/disk/by-label,
>> /dev/disk/by-id, /dev/disk/by-uuid, and if gpt /dev/disk/by-partlabel
>> and /dev/disk/by-partuuid
>
> Explain that to my bootloader. Kernel needs root= on a command line.

It does need a root parameter.  Use root=PARTUUID=<partition UUID>.
Note the UUID is the PARTUUID from "blkid" which is for the partition,
not the UUID field which is for the filesystem.


>> As you found, /dev/sdX bus names are assigned in the order they are
>> added, which for some time has not been guaranteed to remain
>> consistent between kernel versions or even subsequent boots on the
>> same kernel.
>
> Well, for usb, order is not guaranteed, for SATA, it worked. So that's
> a regression in v4.8-rc1.
>
> Yes, /dev/disk/by-* is good idea, but this broke my boot, probably
> broke some scripts that used for a long time... and kernel may not
> break working systems.

It's always possible others may disagree, but I don't think something
is a regression when what breaks has long been said to not be expected
to work.