edit mount failure on swap partition

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
https://iso.qa.ubuntu.com/qatracker/reports/bugs/2002413

From the logs, we see two distinct calls to ModifyPartitionV2 for the swap partition:

2023-01-10 15:03:47,890 DEBUG subiquity.server.controllers.filesystem:775 ModifyPartitionV2(disk_id='disk-sda', partition=Partition(size=8589934592, number=2, preserve=True, wipe=None, annotations=['existing', 'already formatted as swap', 'unused'], mount=None, format='swap', grub_device=False, boot=False, os=None, offset=269484032, estimated_min_size=1048576, resize=None, path='/dev/sda2'))

2023-01-10 15:04:15,912 DEBUG subiquity.server.controllers.filesystem:775 ModifyPartitionV2(disk_id='disk-sda', partition=Partition(size=8589934592, number=2, preserve=True, wipe=None, annotations=['existing', 'already formatted as swap', 'used'], mount='', format='swap', grub_device=False, boot=False, os=None, offset=269484032, estimated_min_size=1048576, resize=None, path='/dev/sda2'))

The value of the mount argument changes from mount=None to mount='' but I was able to reproduce the exception with two calls with mount=None so it is not the root cause of the error.

For normal filesystems, we create the "mount" as part of the FilesystemManipulator.create_mount() method. There is a guard clause that returns immediately if the mount parameter is None.

https://github.com/canonical/subiquity/blob/d3099728eaa17247c02bfbf3935970669f7d0521/subiquity/common/filesystem/manipulator.py#L32
    def create_mount(self, fs, spec):
        if spec.get('mount') is None:
            return
        mount = self.model.add_mount(fs, spec['mount'])

That said, for the swap, we create the mount one level higher, where the guard clause does not look for the mount parameter:

https://github.com/canonical/subiquity/blob/d3099728eaa17247c02bfbf3935970669f7d0521/subiquity/common/filesystem/manipulator.py#L69
        if spec.get('fstype') == "swap":
            self.model.add_mount(fs, "")
        if spec.get('fstype') is None and spec.get('use_swap'):
            self.model.add_mount(fs, "")
        self.create_mount(fs, spec)

I believe this inconsistency is what causes the exception. I'm not sure what's the right way to fix it though.

Yes, iI think I changed from mount none to mount yes.
thjanks

Corrado Venturini

Il giorno lun 16 gen 2023 alle ore 11:30 Olivier Gayot <
<email address hidden>> ha scritto:

> From the logs, we see two distinct calls to ModifyPartitionV2 for the
> swap partition:
>
> 2023-01-10 15:03:47,890 DEBUG
> subiquity.server.controllers.filesystem:775
> ModifyPartitionV2(disk_id='disk-sda',
> partition=Partition(size=8589934592, number=2, preserve=True, wipe=None,
> annotations=['existing', 'already formatted as swap', 'unused'],
> mount=None, format='swap', grub_device=False, boot=False, os=None,
> offset=269484032, estimated_min_size=1048576, resize=None,
> path='/dev/sda2'))
>
> 2023-01-10 15:04:15,912 DEBUG
> subiquity.server.controllers.filesystem:775
> ModifyPartitionV2(disk_id='disk-sda',
> partition=Partition(size=8589934592, number=2, preserve=True, wipe=None,
> annotations=['existing', 'already formatted as swap', 'used'], mount='',
> format='swap', grub_device=False, boot=False, os=None, offset=269484032,
> estimated_min_size=1048576, resize=None, path='/dev/sda2'))
>
> The value of the mount argument changes from mount=None to mount='' but
> I was able to reproduce the exception with two calls with mount=None so
> it is not the root cause of the error.
>
> For normal filesystems, we create the "mount" as part of the
> FilesystemManipulator.create_mount() method. There is a guard clause
> that returns immediately if the mount parameter is None.
>
>
> https://github.com/canonical/subiquity/blob/d3099728eaa17247c02bfbf3935970669f7d0521/subiquity/common/filesystem/manipulator.py#L32
> def create_mount(self, fs, spec):
> if spec.get('mount') is None:
> return
> mount = self.model.add_mount(fs, spec['mount'])
>
> That said, for the swap, we create the mount one level higher, where the
> guard clause does not look for the mount parameter:
>
>
> https://github.com/canonical/subiquity/blob/d3099728eaa17247c02bfbf3935970669f7d0521/subiquity/common/filesystem/manipulator.py#L69
> if spec.get('fstype') == "swap":
> self.model.add_mount(fs, "")
> if spec.get('fstype') is None and spec.get('use_swap'):
> self.model.add_mount(fs, "")
> self.create_mount(fs, spec)
>
> I believe this inconsistency is what causes the exception. I'm not sure
> what's the right way to fix it though.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/2002413
>
> Title:
> request to /storage/v2/edit_partition crashed with Exception
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/subiquity/+bug/2002413/+subscriptions
>
>

https://github.com/canonical/subiquity/pull/1652

We believe this issue has been resolved in Subiquity 23.04.2.

If you had tested this with a pre-final version of Ubuntu 23.04, it's
recommended to download the final install media.

For testing with Ubuntu Server 22.04.x or 20.04.x, when running
Subiquity, you should offered a new version of the installer. Please
take that update to version 23.04.2 or later to get the fix.

If this is still a problem for you, please make a comment and set the state
back to New. Thank you for the bug report.

okay im pretty new to this i did add this to my usb and decied to give it a try i did have debian 11 for a few days and i saw this new os, so i installed and deleted the swap partition there for i dont know.