F36 Change: Wayland by Default for SDDM (Self-Contained Change proposal)

[Ben Cotton]

https://fedoraproject.org/wiki/Changes/WaylandByDefaultForSDDM

= Wayland by Default for SDDM =

== Summary ==
Change the default display server mode for SDDM to use a Wayland-based
greeter rather than an X11-based one.

== Owner ==
* Name: [[User:Ngompa|Neal Gompa]], [[User:Rdieter|Rex Dieter]],
[[User:Jgrulich|Jan Grulich]]
* Email: [e-mail], [e-mail], [e-mail]
* Product: KDE Spin, Kinoite
* Responsible WG: KDE SIG

== Detailed Description ==
With [https://github.com/sddm/sddm/pull/1393 the work done upstream in
SDDM to support using a Wayland based greeter] and
[[Changes/ReplaceFbdevDrivers|the introduction of SimpleDRM to fix the
broken fallback when platform drivers are unavailable]], it is now
possible for the Fedora KDE variants (the regular spin and Kinoite) to
move to Wayland for the login manager, which effectively completes the
switch to Wayland for these variants.

== Benefit to Fedora ==
As originally detailed in [[Changes/WaylandByDefaultForPlasma|the
Change to switch Plasma to Wayland by default]], Fedora is a leader in
advancing the adoption of the Wayland protocol as part of the overall
strategy to improve the Linux graphical software stack. We have been
successful in helping drive Wayland forward in the Plasma Desktop, and
we intend to do the same for SDDM.

== Scope ==
* Proposal owners:
** Upgrade {{package|sddm}} to the latest snapshot and introduce
mutually exclusive <code>sddm-wayland-generic</code> and
<code>sddm-x11</code> greeter configuration packages.
** Modify {{package|plasma-workspace}} to switch SDDM to Wayland
*** Enable installation of the SDDM Wayland configuration snippet and
ship as <code>sddm-wayland-plasma</code> that is mutually exclusive
with the other sddm greeter configuration packages. This package will
supplement {{package|sddm}} and <code>plasma-workspace-wayland</code>
to be automatically installed together.
** Modify <code>@kde-desktop</code> comps group for Fedora Linux 36 to
include <code>sddm-wayland-plasma</code> for the media.

* Other developers: N/A (not needed for this Change)

* Release engineering: [https://pagure.io/releng/issue/10536 #10536]
* Policies and guidelines: N/A (not needed for this Change)
* Trademark approval: N/A (not needed for this Change)
* Alignment with Objectives: N/A

== Upgrade/compatibility impact ==
On upgrade to Fedora Linux 36, SDDM will be transparently switched
from the X11 greeter to the Wayland one leveraging kwin. In order to
override this, the user can do one of the following:
* Drop in a configuration file in <code>/etc/sddm.conf.d</code> to set
the display server back to X11
* Swap back to X11 with the configuration package: <code>dnf swap
sddm-wayland-plasma sddm-x11</code>

== How To Test ==
Once the SDDM and Plasma Wayland changes are made, Rawhide users can
try this by using nightly KDE ISOs and using them normally to install
and run a Rawhide KDE Plasma environment.

== User Experience ==
Ideally, there should be no noticeable impact on the user experience,
though users may notice that things operate more smoothly and with
slightly lower resources.

== Dependencies ==
This change is dependent on [[Changes/ReplaceFbdevDrivers|the Change
to replace fbdev with SimpleDRM]]. Without that Change, we will need
to keep SDDM using X11 because otherwise the fallbacks are broken when
drivers do not work.

== Contingency Plan ==
* Contingency mechanism: Update comps and {{package|plasma-workspace}}
so that <code>sddm-x11</code> is shipped instead.
* Contingency deadline: beta freeze
* Blocks release? Yes

== Documentation ==
N/A (not a System Wide Change)

== Release Notes ==
SDDM, the login manager for the Fedora variants using the KDE Plasma
Desktop, now uses the Wayland display system.

[Miroslav Suchý]

Dne 18. 01. 22 v 15:28 Ben Cotton napsal(a):
> ** Upgrade {{package|sddm}} to the latest snapshot and introduce
> mutually exclusive <code>sddm-wayland-generic</code> and
> <code>sddm-x11</code> greeter configuration packages.
> ** Modify {{package|plasma-workspace}} to switch SDDM to Wayland
> *** Enable installation of the SDDM Wayland configuration snippet and
> ship as <code>sddm-wayland-plasma</code> that is mutually exclusive
> with the other sddm greeter configuration packages. This package will
> supplement {{package|sddm}} and <code>plasma-workspace-wayland</code>
> to be automatically installed together.

When we switch SDDM to Wayland, will it be still possible from the SDDM to choose whether I want to log in to X11 or 
Wayland? Or Wayland in SDDM enforce Wayland in the Plasma session?

Miroslav

[Neal Gompa]

On Thu, Jan 20, 2022 at 2:11 AM Miroslav Suchý  wrote:
> Dne 18. 01. 22 v 15:28 Ben Cotton napsal(a):
> > ** Upgrade {{package|sddm}} to the latest snapshot and introduce
> > mutually exclusive <code>sddm-wayland-generic</code> and
> > <code>sddm-x11</code> greeter configuration packages.
> > ** Modify {{package|plasma-workspace}} to switch SDDM to Wayland
> > *** Enable installation of the SDDM Wayland configuration snippet and
> > ship as <code>sddm-wayland-plasma</code> that is mutually exclusive
> > with the other sddm greeter configuration packages. This package will
> > supplement {{package|sddm}} and <code>plasma-workspace-wayland</code>
> > to be automatically installed together.
>
> When we switch SDDM to Wayland, will it be still possible from the SDDM to choose whether I want to log in to X11 or
> Wayland? Or Wayland in SDDM enforce Wayland in the Plasma session?

You will still be able to choose to start X11 desktop sessions from
SDDM. This just changes SDDM *itself* to use Wayland.

Note that KDE Plasma already defaults to Wayland, so you will need to
explicitly choose the X11 session.

--
真実はいつも一つ！/ Always, there's only one truth!

[Jonathan Wakely]

On Tue, 18 Jan 2022 at 14:30, Ben Cotton  wrote:
> https://fedoraproject.org/wiki/Changes/WaylandByDefaultForSDDM
>
> = Wayland by Default for SDDM =
>
> == Summary ==
> Change the default display server mode for SDDM to use a Wayland-based
> greeter rather than an X11-based one.
>
> == Owner ==
> Name: [[User:Ngompa|Neal Gompa]], [[User:Rdieter|Rex Dieter]],
>
> [[User:Jgrulich|Jan Grulich]]
> Email: [e-mail], [e-mail], [e-mail]
> Product: KDE Spin, Kinoite
> Responsible WG: KDE SIG
>
> == Detailed Description ==
> With [https://github.com/sddm/sddm/pull/1393 the work done upstream in
> SDDM to support using a Wayland based greeter] and
> [[Changes/ReplaceFbdevDrivers|the introduction of SimpleDRM to fix the
> broken fallback when platform drivers are unavailable]], it is now
> possible for the Fedora KDE variants (the regular spin and Kinoite) to
> move to Wayland for the login manager, which effectively completes the
> switch to Wayland for these variants.
>
> == Benefit to Fedora ==
> As originally detailed in [[Changes/WaylandByDefaultForPlasma|the
> Change to switch Plasma to Wayland by default]], Fedora is a leader in
> advancing the adoption of the Wayland protocol as part of the overall
> strategy to improve the Linux graphical software stack. We have been
> successful in helping drive Wayland forward in the Plasma Desktop, and
> we intend to do the same for SDDM.
>
> == Scope ==
> Proposal owners:
>
> ** Upgrade {{package|sddm}} to the latest snapshot and introduce
> mutually exclusive <code>sddm-wayland-generic</code> and
> <code>sddm-x11</code> greeter configuration packages.
> ** Modify {{package|plasma-workspace}} to switch SDDM to Wayland
> *** Enable installation of the SDDM Wayland configuration snippet and
> ship as <code>sddm-wayland-plasma</code> that is mutually exclusive
> with the other sddm greeter configuration packages. This package will
> supplement {{package|sddm}} and <code>plasma-workspace-wayland</code>
> to be automatically installed together.
> ** Modify <code>@kde-desktop</code> comps group for Fedora Linux 36 to
> include <code>sddm-wayland-plasma</code> for the media.
>
> Other developers: N/A (not needed for this Change)
>
> Release engineering: [https://pagure.io/releng/issue/10536 #10536]
>
> Policies and guidelines: N/A (not needed for this Change)
>
> Trademark approval: N/A (not needed for this Change)
>
> Alignment with Objectives: N/A
>
> == Upgrade/compatibility impact ==
> On upgrade to Fedora Linux 36, SDDM will be transparently switched
> from the X11 greeter to the Wayland one leveraging kwin. In order to
> override this, the user can do one of the following:
> Drop in a configuration file in <code>/etc/sddm.conf.d</code> to set
>
> the display server back to X11
> Swap back to X11 with the configuration package: <code>dnf swap
>
> sddm-wayland-plasma sddm-x11</code>
>
> == How To Test ==
> Once the SDDM and Plasma Wayland changes are made, Rawhide users can
> try this by using nightly KDE ISOs and using them normally to install
> and run a Rawhide KDE Plasma environment.
>
> == User Experience ==
> Ideally, there should be no noticeable impact on the user experience,
> though users may notice that things operate more smoothly and with
> slightly lower resources.

Last time I tried, I couldn't use Synergy and Wayland together, so I
use X11 sessions with KDE still. Will this change only affect the
pre-login greeter screen, or does it also affect the lock screen when
a running X11 session is locked (either explicitly or after the
timeout)? Currently I can still use the mouse and keyboard from a
different machine to unlock that lock screen. If it starts using
Wayland that won't work. It might be worth mentioning that for the
user experience for other Synergy users.

[Neal Gompa]

On Wed, Feb 9, 2022 at 5:24 AM Jonathan Wakely  wrote:
> On Tue, 18 Jan 2022 at 14:30, Ben Cotton  wrote:
> > https://fedoraproject.org/wiki/Changes/WaylandByDefaultForSDDM
> >
> > = Wayland by Default for SDDM =
> >
> > == Summary ==
> > Change the default display server mode for SDDM to use a Wayland-based
> > greeter rather than an X11-based one.
> >
> > == Owner ==
> > Name: [[User:Ngompa|Neal Gompa]], [[User:Rdieter|Rex Dieter]],
> >
> > [[User:Jgrulich|Jan Grulich]]
> > Email: [e-mail], [e-mail], [e-mail]
> > Product: KDE Spin, Kinoite
> > Responsible WG: KDE SIG
> >
> > == Detailed Description ==
> > With [https://github.com/sddm/sddm/pull/1393 the work done upstream in
> > SDDM to support using a Wayland based greeter] and
> > [[Changes/ReplaceFbdevDrivers|the introduction of SimpleDRM to fix the
> > broken fallback when platform drivers are unavailable]], it is now
> > possible for the Fedora KDE variants (the regular spin and Kinoite) to
> > move to Wayland for the login manager, which effectively completes the
> > switch to Wayland for these variants.
> >
> > == Benefit to Fedora ==
> > As originally detailed in [[Changes/WaylandByDefaultForPlasma|the
> > Change to switch Plasma to Wayland by default]], Fedora is a leader in
> > advancing the adoption of the Wayland protocol as part of the overall
> > strategy to improve the Linux graphical software stack. We have been
> > successful in helping drive Wayland forward in the Plasma Desktop, and
> > we intend to do the same for SDDM.
> >
> > == Scope ==
> > Proposal owners:
> >
> > ** Upgrade {{package|sddm}} to the latest snapshot and introduce
> > mutually exclusive <code>sddm-wayland-generic</code> and
> > <code>sddm-x11</code> greeter configuration packages.
> > ** Modify {{package|plasma-workspace}} to switch SDDM to Wayland
> > *** Enable installation of the SDDM Wayland configuration snippet and
> > ship as <code>sddm-wayland-plasma</code> that is mutually exclusive
> > with the other sddm greeter configuration packages. This package will
> > supplement {{package|sddm}} and <code>plasma-workspace-wayland</code>
> > to be automatically installed together.
> > ** Modify <code>@kde-desktop</code> comps group for Fedora Linux 36 to
> > include <code>sddm-wayland-plasma</code> for the media.
> >
> > Other developers: N/A (not needed for this Change)
> >
> > Release engineering: [https://pagure.io/releng/issue/10536 #10536]
> >
> > Policies and guidelines: N/A (not needed for this Change)
> >
> > Trademark approval: N/A (not needed for this Change)
> >
> > Alignment with Objectives: N/A
> >
> > == Upgrade/compatibility impact ==
> > On upgrade to Fedora Linux 36, SDDM will be transparently switched
> > from the X11 greeter to the Wayland one leveraging kwin. In order to
> > override this, the user can do one of the following:
> > Drop in a configuration file in <code>/etc/sddm.conf.d</code> to set
> >
> > the display server back to X11
> > Swap back to X11 with the configuration package: <code>dnf swap
> >
> > sddm-wayland-plasma sddm-x11</code>
> >
> > == How To Test ==
> > Once the SDDM and Plasma Wayland changes are made, Rawhide users can
> > try this by using nightly KDE ISOs and using them normally to install
> > and run a Rawhide KDE Plasma environment.
> >
> > == User Experience ==
> > Ideally, there should be no noticeable impact on the user experience,
> > though users may notice that things operate more smoothly and with
> > slightly lower resources.
>
> Last time I tried, I couldn't use Synergy and Wayland together, so I
> use X11 sessions with KDE still. Will this change only affect the
> pre-login greeter screen, or does it also affect the lock screen when
> a running X11 session is locked (either explicitly or after the
> timeout)? Currently I can still use the mouse and keyboard from a
> different machine to unlock that lock screen. If it starts using
> Wayland that won't work. It might be worth mentioning that for the
> user experience for other Synergy users.

SDDM only affects pre-login, just like GDM for GNOME. If you select
X11 at login, the lock screen will also use X11.

--
真実はいつも一つ！/ Always, there's only one truth!

[Jonathan Wakely]

On Wed, 9 Feb 2022 at 11:00, Neal Gompa  wrote:
> On Wed, Feb 9, 2022 at 5:24 AM Jonathan Wakely  wrote:
> > On Tue, 18 Jan 2022 at 14:30, Ben Cotton  wrote:
> > > https://fedoraproject.org/wiki/Changes/WaylandByDefaultForSDDM
> > >
> > > = Wayland by Default for SDDM =
> > >
> > > == Summary ==
> > > Change the default display server mode for SDDM to use a Wayland-based
> > > greeter rather than an X11-based one.
> > >
> > > == Owner ==
> > > Name: [[User:Ngompa|Neal Gompa]], [[User:Rdieter|Rex Dieter]],
> > >
> > > [[User:Jgrulich|Jan Grulich]]
> > > Email: [e-mail], [e-mail], [e-mail]
> > > Product: KDE Spin, Kinoite
> > > Responsible WG: KDE SIG
> > >
> > > == Detailed Description ==
> > > With [https://github.com/sddm/sddm/pull/1393 the work done upstream in
> > > SDDM to support using a Wayland based greeter] and
> > > [[Changes/ReplaceFbdevDrivers|the introduction of SimpleDRM to fix the
> > > broken fallback when platform drivers are unavailable]], it is now
> > > possible for the Fedora KDE variants (the regular spin and Kinoite) to
> > > move to Wayland for the login manager, which effectively completes the
> > > switch to Wayland for these variants.
> > >
> > > == Benefit to Fedora ==
> > > As originally detailed in [[Changes/WaylandByDefaultForPlasma|the
> > > Change to switch Plasma to Wayland by default]], Fedora is a leader in
> > > advancing the adoption of the Wayland protocol as part of the overall
> > > strategy to improve the Linux graphical software stack. We have been
> > > successful in helping drive Wayland forward in the Plasma Desktop, and
> > > we intend to do the same for SDDM.
> > >
> > > == Scope ==
> > > Proposal owners:
> > >
> > > ** Upgrade {{package|sddm}} to the latest snapshot and introduce
> > > mutually exclusive <code>sddm-wayland-generic</code> and
> > > <code>sddm-x11</code> greeter configuration packages.
> > > ** Modify {{package|plasma-workspace}} to switch SDDM to Wayland
> > > *** Enable installation of the SDDM Wayland configuration snippet and
> > > ship as <code>sddm-wayland-plasma</code> that is mutually exclusive
> > > with the other sddm greeter configuration packages. This package will
> > > supplement {{package|sddm}} and <code>plasma-workspace-wayland</code>
> > > to be automatically installed together.
> > > ** Modify <code>@kde-desktop</code> comps group for Fedora Linux 36 to
> > > include <code>sddm-wayland-plasma</code> for the media.
> > >
> > > Other developers: N/A (not needed for this Change)
> > >
> > > Release engineering: [https://pagure.io/releng/issue/10536 #10536]
> > >
> > > Policies and guidelines: N/A (not needed for this Change)
> > >
> > > Trademark approval: N/A (not needed for this Change)
> > >
> > > Alignment with Objectives: N/A
> > >
> > > == Upgrade/compatibility impact ==
> > > On upgrade to Fedora Linux 36, SDDM will be transparently switched
> > > from the X11 greeter to the Wayland one leveraging kwin. In order to
> > > override this, the user can do one of the following:
> > > Drop in a configuration file in <code>/etc/sddm.conf.d</code> to set
> > >
> > > the display server back to X11
> > > Swap back to X11 with the configuration package: <code>dnf swap
> > >
> > > sddm-wayland-plasma sddm-x11</code>
> > >
> > > == How To Test ==
> > > Once the SDDM and Plasma Wayland changes are made, Rawhide users can
> > > try this by using nightly KDE ISOs and using them normally to install
> > > and run a Rawhide KDE Plasma environment.
> > >
> > > == User Experience ==
> > > Ideally, there should be no noticeable impact on the user experience,
> > > though users may notice that things operate more smoothly and with
> > > slightly lower resources.
> >
> > Last time I tried, I couldn't use Synergy and Wayland together, so I
> > use X11 sessions with KDE still. Will this change only affect the
> > pre-login greeter screen, or does it also affect the lock screen when
> > a running X11 session is locked (either explicitly or after the
> > timeout)? Currently I can still use the mouse and keyboard from a
> > different machine to unlock that lock screen. If it starts using
> > Wayland that won't work. It might be worth mentioning that for the
> > user experience for other Synergy users.
>
> SDDM only affects pre-login, just like GDM for GNOME. If you select
> X11 at login, the lock screen will also use X11.

Great, thanks!

På Wed, 9 Feb 2022 05:59:03 -0500
Neal Gompa  skrev:
> On Wed, Feb 9, 2022 at 5:24 AM Jonathan Wakely 
> wrote:
> > Last time I tried, I couldn't use Synergy and Wayland together, so I
> > use X11 sessions with KDE still. Will this change only affect the
> > pre-login greeter screen, or does it also affect the lock screen
> > when a running X11 session is locked (either explicitly or after the
> > timeout)? Currently I can still use the mouse and keyboard from a
> > different machine to unlock that lock screen. If it starts using
> > Wayland that won't work. It might be worth mentioning that for the
> > user experience for other Synergy users.
>
> SDDM only affects pre-login, just like GDM for GNOME. If you select
> X11 at login, the lock screen will also use X11.

So when using Synergy on login screen - that will stop working for me
with this change ?  
Is there an easy way to set it back to X11 ?

Allan.

[Neal Gompa]

On Wed, Feb 9, 2022 at 5:46 PM allan2016--- via devel
 wrote:
> På Wed, 9 Feb 2022 05:59:03 -0500
> Neal Gompa  skrev:
> > On Wed, Feb 9, 2022 at 5:24 AM Jonathan Wakely 
> > wrote:
> > > Last time I tried, I couldn't use Synergy and Wayland together, so I
> > > use X11 sessions with KDE still. Will this change only affect the
> > > pre-login greeter screen, or does it also affect the lock screen
> > > when a running X11 session is locked (either explicitly or after the
> > > timeout)? Currently I can still use the mouse and keyboard from a
> > > different machine to unlock that lock screen. If it starts using
> > > Wayland that won't work. It might be worth mentioning that for the
> > > user experience for other Synergy users.
> >
> > SDDM only affects pre-login, just like GDM for GNOME. If you select
> > X11 at login, the lock screen will also use X11.
>
> So when using Synergy on login screen - that will stop working for me
> with this change ?
> Is there an easy way to set it back to X11 ?

Yes. A user can revert using the steps documented in the Change document.

https://fedoraproject.org/wiki/Changes/WaylandByDefaultForSDDM#Upgrade.2Fcom...

[Tom Seewald]

How will multi-monitor users be able to configure the display arrangement for SDDM now? Currently on my desktop SDDM defaults to an incorrect arrangement and I have /etc/sddm/Xsetup call xrandr to correct it. With SDDM using wayland by default will users just be expected to deal with random monitor arrangements during the login experience?