pathless nvme drive crashes block discovery

[Dimitri John Ledkov]

pathless nvme drive crashes block discovery

I have an nvme drive, and a regular sda usb stick plugged in.

Somehow multipath declares a path to my nmve drive.... without any map setup.

This seems to crash everything.

[Dimitri John Ledkov (xnox)]

2019-10-11 14:49:46,529 curtin:1230 Validation error: None is not of type 'string' in
{
 "id": "disk-sda",
 "multipath": null,
 "path": "/dev/sda",
 "ptable": "dos",
 "serial": "SanDisk_Ultra_USB_3.0_4C530001200208100222-0:0",
 "type": "disk"
}
NoneType: None

The null in multipath is weird, but check this out - a mapless multipath:

    "multipath": {
        "paths": [
            {
                "device": "nvme0n1",
                "serial": "27FF079419DE00131387",
                "multipath": "[orphan]",
                "host_wwnn": "[undef]",
                "target_wwnn": "[undef]",
                "host_wwpn": "[undef]",
                "target_wwpn": "[undef]",
                "host_adapter": "[undef]"
            }
        ]
    },

[Dimitri John Ledkov (xnox)]

  File "/usr/lib/python3/dist-packages/curtin/storage_config.py", line 1232, in extract_storage_config
    raise RuntimeError("Extract storage config does not validate.")
RuntimeError: Extract storage config does not validate.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Michael Hudson-Doyle (mwhudson)]

Yeah, I have a similar config in my laptop, and:

(master)mwhudson@anduril:~/src/probert$ sudo multipathd show paths
hcil dev dev_t pri dm_st chk_st dev_st next_check
0:1:1:1 nvme0n1 259:0 1 undef undef unknown orphan
(master)mwhudson@anduril:~/src/probert$ sudo multipathd show maps
(master)mwhudson@anduril:~/src/probert$

what is going on.

[Michael Hudson-Doyle (mwhudson)]

Ah so curtin takes DM_MULTIPATH_DEVICE_PATH being set at all as an indication of a multipath device, but per the follow up to https://www.spinics.net/lists/dm-devel/msg35965.html that's wrong: only a value of "1" indicates a multipath device.

[Michael Hudson-Doyle (mwhudson)]

This is fixed in the stable/ubuntu-19.10 channel now. If you boot an eoan daily (up to and including 20191014, the next one will contain the fix), it will offer to update you to 19.10.2 which should then be able to complete the install.

[Dan Watkins (oddbloke)]

Dropped the Ubuntu tasks as (IIUC) the code that caused this problem isn't in the Ubuntu package, we're only seeing it because subiquity is/was consuming curtin master.