licence: SchOS is GPL-2.0-or-later, no longer Apache-2.0

Nexoniarz is the sole author and SchOS was never published under Apache-2.0, so this is a straight relicence. LICENSE is the FSF GPLv2 text, every first-party SPDX header moves to GPL-2.0-or-later, and NOTICE, README.md, docs/licensing.md and the site say so. projects/schfs-linux follows the rest of the tree. The GPL gives copyleft: a fork has to ship its source. It also lifts the old "Linux drivers, never" rule, since GPL-2.0-only code combines with GPL-2.0-or-later. "Or later" leaves room for GPLv3, but one binary still has to pick one version, so docs/licensing.md now keeps Apache-2.0 and GPLv3 code out of the kernel to keep Linux code possible there. BSD 4-clause code goes from "avoid" to "no", because the advertising clause is GPL-incompatible. LDLS still ships no .ko. That boundary is now project policy rather than a legal requirement, and ldls.md, devices.md and licensing.md section 6 say so. refmod declares license=GPL, and ldls-check passes (27 checks). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-22 08:48:45 +02:00 · 2026-10-22 08:48:45 +02:00 · 26bca020b6
commit 26bca020b6
parent 3b26575b4a
135 changed files with 959 additions and 689 deletions
--- a/.claude/memory/MEMORY.md
+++ b/.claude/memory/MEMORY.md
@ -44,7 +44,7 @@
 - [Device model](schunix-device-model.md) — one bus-agnostic list at /proc/devices; bus is provenance, class is capability, and the settled Linux-driver decision.
 - [usb.ids](schunix-usb-ids.md) — shipped as /usr/share/usb.ids, BSD option of a dual licence; cached, not fetched per build.
 - [USB and xHCI](schunix-usb-xhci.md) — enumeration and control transfers work; written from the spec, because porting BSD's stack means porting newbus first.
- [Licensing](schunix-licensing.md) — Apache-2.0, copyright Nexoniarz; BSD drivers are usable and Linux ones are not.
+- [Licensing](schunix-licensing.md) — GPL-2.0-or-later since 2026-10-22 (was Apache); Linux code OK, no Apache/GPLv3 in the kernel.
 - [Layout migration](schunix-layout-migration.md) — the bt/ → ports/ + lib/ + cmd/ restructure and the two Makefile traps it exposed.
 - [Verify by driving the shell](schunix-verify-by-driving-shell.md) — booting to a prompt proves nothing; run real commands over serial with paced input.
 - [/dev and /proc](schunix-devfs-procfs.md) — how both are built; ps and top work now, one cosmetic gap left.
--- a/.claude/memory/schunix-licensing.md
+++ b/.claude/memory/schunix-licensing.md
@ -1,6 +1,6 @@
 ---
 name: schunix-licensing
-description: "Schunix is Apache-2.0, copyright Nexoniarz; BSD drivers yes, Linux no, and ports/ licences bind regardless"
+description: "SchOS is GPL-2.0-or-later since 2026-10-22 (was Apache-2.0); Linux code now allowed, but no Apache/GPLv3 code in the kernel"
 metadata: 
  node_type: memory
  type: project
@ -8,43 +8,34 @@ metadata:
  modified: 2026-08-08T16:18:39.569Z
 ---
-**`LICENSE` is Apache-2.0**, copyright *Nexoniarz* (not "Schunix Contributors" —
+**`LICENSE` is GPL-2.0-or-later** since 2026-10-22, copyright *Nexoniarz*, sole
-one author, and a fictional collective makes future re-licensing harder).
+author. It was Apache-2.0 before and was never published under it. Nexoniarz
-Chosen over MIT/BSD for the express patent grant.
+chose GPL for copyleft ("I can't be also too liberal because people just mostly
 steal that work") and so Linux code can be used. They picked "or-later" over
 "only" on my recommendation.
-**Settled, do not reopen:** the "Apache-2.0 but shared-source" question was
+**The rule that replaced "Linux no":** a single linked binary has to pick one
-discussed at length in 2026-08 and **on 2026-08-08 Nexoniarz asked for it to be
+GPL version. Linux code (GPL-2.0-only) makes it GPLv2; Apache-2.0 or GPLv3 code
-dropped from the docs entirely** — `docs/licensing.md` is about licensing, not
+makes it GPLv3. They can't share a binary, so **the kernel takes no Apache-2.0
-about that debate. All references are gone from `docs/`, `LICENSE` and `NOTICE`;
+or GPLv3 code**. Separate userland programs may be GPLv3 or Apache. Data files
-don't reintroduce them. The substance that survives, in one line inside §1:
+such as Roboto (Apache-2.0) are aggregation, and that holds inside the ramdisk
-Apache-2.0 §2 is an irrevocable grant, so a restriction stated anywhere else
+too. BSD 4-clause code is now a hard **no** (GPL-incompatible).
 does not narrow it, and restricting distribution would be a licence change
 (bespoke proprietary, or BUSL-1.1) rather than a wording change.
-The decision that actually mattered to them is **when to publish**, not the
+**LDLS still ships no `.ko`.** That is policy now, not a legal requirement. The
-licence; the standing rule is still never ([[nexoniarz-sharing-preference]]).
+`.gitignore` `*.ko` rule and `RAMDISK_EXCLUDE` stay.
-**Binding regardless of what they pick:**
+**Settled, do not reopen:** the old "Apache-2.0 but shared-source" debate was
- The kernel derives from xv6 (MIT). `LICENSE.MIT` was *missing* — it was
+dropped from the docs on 2026-08-08. The question that matters to them is when
-  referenced as `bk/LICENSE.MIT` and lost in the `bk/` → `kernel/` migration.
+to publish, and the standing answer is still never
-  Recreated; must not be deleted.
+([[nexoniarz-sharing-preference]]).
 - `ports/` is other people's code, redistributed in every image: musl (MIT),
  toybox (0BSD), mksh (MirOS). `NOTICE` carries the attribution musl and mksh
  require. Patches under `ports/*/patches/` inherit *their* licences.
-New first-party files carry `// SPDX-License-Identifier: Apache-2.0`.
+**Binding regardless:**
 - The kernel derives from xv6 (MIT). `LICENSE.MIT` must not be deleted.
 - `ports/` is other people's code: musl, toybox, mksh, zsh, ncurses, lwIP,
  kilo and fastfetch are all permissive. `NOTICE` carries the attributions.
-**Drivers: BSD yes, Linux no** (asked 2026-08-04, "for drivers we can try get
+New first-party files carry `// SPDX-License-Identifier: GPL-2.0-or-later`.
-it from like Linux?"). Linux is GPL-2.0-**only**, and Apache-2.0's patent and
+The policy is in `docs/licensing.md`. See [[schunix-roadmap-and-projects]].
 indemnity clauses are "further restrictions" under GPLv2 §6 — the two cannot
 be combined and redistributed. Using a Linux driver means relicensing all of
 Schunix to GPLv2 and dropping Apache-2.0; you cannot keep both. FreeBSD /
 NetBSD / OpenBSD are BSD-2/3-clause and **are** compatible: keep the notice,
 add to `NOTICE`, done. Reading Linux to understand hardware is fine;
 translating a driver function-by-function produces a derivative work whatever
 the identifiers say. Best source of all is the public specification — xHCI,
 virtio, AHCI, NVMe, e1000 — which carries no licence on what you write from
 it. Recorded in `docs/plan/roadmap.md` §1. See [[schunix-roadmap-and-projects]].
 ## fs.c is third-party, and was unattributed until 2026-08-09
--- a/.gitignore
+++ b/.gitignore
@ -45,7 +45,8 @@ docs/Website/releases/
 # Kernel modules, ever. docs/plan/ldls.md rule 1: LDLS ships the layer and
 # never the thing it loads, and that applies to this tree as well as to an
 # image. The loader's test input is built from ldls/test/refmod.c, which is
-# ours; a .ko here would be someone else's GPL code in an Apache-2.0 repo.
+# ours; a .ko here would be someone else's code, with its own provenance, in
 # a tree that is otherwise all first-party or attributed in NOTICE.
 *.ko
 *.ko.xz
@ -59,7 +60,7 @@ core.*
 #
 # help/ is where a third-party kernel gets cloned when it is worth reading --
 # Zircon, at the time of writing. It is BSD-licensed and this project is
-# Apache-2.0, so the licences are compatible and that is *not* the reason it is
+# GPL-2.0-or-later, so the licences are compatible and that is *not* the reason it is
 # ignored: it is ignored because a copy of another project's source inside this
 # one is a copy that will rot, that nobody will update, and that makes the
 # provenance of every file around it a question. Clone it, read it, learn the
--- a/462
+++ b/462
@ -1,187 +1,339 @@
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+  6. Each time you redistribute the Program (or any work based on the
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 You are not responsible for enforcing compliance by third parties to
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 the limitation as if written in the body of this License.
  9. The Free Software Foundation may publish revised and/or new versions
 of the General Public License from time to time.  Such new versions will
 be similar in spirit to the present version, but may differ in detail to
 address new problems or concerns.
 Each version is given a distinguishing version number.  If the Program
 specifies a version number of this License which applies to it and "any
 later version", you have the option of following the terms and conditions
 either of that version or of any later version published by the Free
 Software Foundation.  If the Program does not specify a version number of
 this License, you may choose any version ever published by the Free Software
 Foundation.
  10. If you wish to incorporate parts of the Program into other free
 programs whose distribution conditions are different, write to the author
 to ask for permission.  For software which is copyrighted by the Free
 Software Foundation, write to the Free Software Foundation; we sometimes
 make exceptions for this.  Our decision will be guided by the two goals
 of preserving the free status of all derivatives of our free software and
 of promoting the sharing and reuse of software generally.
                            NO WARRANTY
  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
 PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
 OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
 TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
 PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
 REPAIR OR CORRECTION.
  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
 REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
 INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
 OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
 TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
 YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
 POSSIBILITY OF SUCH DAMAGES.
                     END OF TERMS AND CONDITIONS
            How to Apply These Terms to Your New Programs
  If you develop a new program, and you want it to be of the greatest
 possible use to the public, the best way to achieve this is to make it
 free software which everyone can redistribute and change under these terms.
  To do so, attach the following notices to the program.  It is safest
 to attach them to the start of each source file to most effectively
 convey the exclusion of warranty; and each file should have at least
 the "copyright" line and a pointer to where the full notice is found.
    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 Also add information on how to contact you by electronic and paper mail.
 If the program is interactive, make it output a short notice like this
 when it starts in an interactive mode:
    Gnomovision version 69, Copyright (C) year name of author
    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.
 The hypothetical commands `show w' and `show c' should show the appropriate
 parts of the General Public License.  Of course, the commands you use may
 be called something other than `show w' and `show c'; they could even be
 mouse-clicks or menu items--whatever suits your program.
 You should also get your employer (if you work as a programmer) or your
 school, if any, to sign a "copyright disclaimer" for the program, if
 necessary.  Here is a sample; alter the names:
  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
  `Gnomovision' (which makes passes at compilers) written by James Hacker.
  <signature of Ty Coon>, 1 April 1989
  Ty Coon, President of Vice
 This General Public License does not permit incorporating your program into
 proprietary programs.  If your program is a subroutine library, you may
 consider it more useful to permit linking proprietary applications with the
 library.  If this is what you want to do, use the GNU Lesser General
 Public License instead of this License.
--- a/4
+++ b/4
@ -455,8 +455,8 @@ RAMDISK_BLOCKS ?= 8000
 # rule before it is a size one: the ramdisk image is linked *into the kernel
 # binary*, so anything staged in sysroot/ when it is built becomes part of a
 # distributable artifact. Anything that arrives in sysroot/ under a licence that
-# cannot be combined with Apache-2.0, or that simply is not ours to redistribute,
+# cannot be combined with GPL-2.0-or-later, or that simply is not ours to
-# belongs on this list rather than in someone's memory.
+# redistribute, belongs on this list rather than in someone's memory.
 #
 # This is not hypothetical: a 33 MB test payload once landed here and overflowed
 # the 6 MB image, and mkfs's "increase FSSIZE" message then pointed at a constant
--- a/23
+++ b/23
@ -2,7 +2,8 @@ SchOS
 Copyright 2026 Nexoniarz
 This product includes software developed as part of the SchOS project,
-licensed under the Apache License, Version 2.0. See LICENSE.
+licensed under the GNU General Public License, version 2 or (at your option)
 any later version. See LICENSE.
 ================================================================================
 Third-party software
@ -118,9 +119,9 @@ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 Fetched by ports/lwip and compiled into the kernel -- it is the TCP/IP stack,
 not a userland library, so it is present in every built kernel image rather
 than in a binary under /bin. The port layer written for SchOS
-(kernel/net/lwip/) is Apache-2.0 and is not part of lwIP; lwIP's own sources
+(kernel/net/lwip/) is GPL-2.0-or-later and is not part of lwIP; lwIP's own
-are unmodified. Clause 3 is a no-endorsement term, not the four-clause
+sources are unmodified. Clause 3 is a no-endorsement term, not the four-clause
-advertising requirement, so it combines with Apache-2.0 without difficulty.
+advertising requirement, so it combines with the GPL without difficulty.
 --------------------------------------------------------------------------------
 Intel 8254x device identifiers                                BSD 3-Clause
@ -149,9 +150,8 @@ http://www.linux-usb.org/usb.ids
 Distributed by its maintainer under the terms of *either* the GNU General
 Public License version 2 or later, *or* the 3-clause BSD Licence. SchOS takes
-the BSD option; the GPL option is not exercised and could not be, since
+the BSD option, which was chosen while SchOS was Apache-2.0; either option is
-Apache-2.0 and GPL-2.0-only cannot be combined (see docs/licensing.md section
+compatible now, and the BSD one is kept because it asks less of anyone.
 2).
 Shipped verbatim as /usr/share/usb.ids. Cached in dist/ and refreshed with
 `make usb-ids`, never automatically -- the version and date are in the file's
@ -163,9 +163,10 @@ Roboto                                                        Apache-2.0
 Copyright the Roboto Project Authors (https://github.com/googlefonts/roboto)
 Shipped as /usr/share/fonts/Roboto-Regular.ttf, from ports/Roboto. Licensed
-under Apache-2.0 -- the same licence as SchOS itself, so it carries no
+under Apache-2.0. It is a separate data file loaded at run time, not code
-obligation beyond this notice. Intended for the desktop, window manager and
+linked into SchOS, so it sits beside the GPL as an aggregate and keeps its own
-compositor.
+licence; the obligation is this notice. Intended for the desktop, window
 manager and compositor.
 --------------------------------------------------------------------------------
 JetBrains Mono                                                SIL OFL 1.1
@ -178,7 +179,7 @@ Shipped as /usr/share/fonts/JetBrainsMono-Regular.ttf, from ports/JetBrains_Mono
 and TTY.
 Under the SIL Open Font License 1.1 the font remains under OFL even inside this
-Apache-2.0 system -- that does not reach any other part of SchOS -- and it may
+GPL-licensed system -- that does not reach any other part of SchOS -- and it may
 not be sold on its own. Bundling it with an operating system is expressly
 permitted. JetBrains Mono declares no Reserved Font Name, so a modified version
 (a pre-rasterised bitmap, for instance) may keep the name.
--- a/README.md
+++ b/README.md
@ -150,20 +150,17 @@ Another: **syscalls are declared in exactly one place**,
 ## Licensing
-**Apache-2.0**, copyright Nexoniarz. See [LICENSE](LICENSE).
+**GPL-2.0-or-later**, copyright Nexoniarz. See [LICENSE](LICENSE).
 The kernel derives from xv6, which is MIT — see [LICENSE.MIT](LICENSE.MIT).
 Third-party code redistributed in a built image (musl, toybox, mksh, zsh, kilo,
 the fonts) keeps its own licence; [NOTICE](NOTICE) carries the attributions.
-All of it is permissive — there is no GPL in an image this builds, which is why
+See [docs/licensing.md](docs/licensing.md).
 the userland is toybox and not BusyBox and the editor is kilo and not nano. See
 [docs/licensing.md](docs/licensing.md).
-Drivers may be adapted from BSD sources, which are compatible. Linux drivers are
+Drivers may be adapted from BSD sources and, since the move to the GPL, from
-not: GPL-2.0-only and Apache-2.0 cannot be combined and redistributed. Reading
+Linux — GPL-2.0-only code combines with GPL-2.0-or-later, and the result ships
-Linux to understand hardware is fine; translating a driver is not. Best of all
+under GPLv2. Best of all is still the public specification — xHCI, virtio,
-is the public specification — xHCI, virtio, AHCI, e1000 — which carries no
+AHCI, e1000 — which carries no licence on what you write from it.
 licence on what you write from it.
 ---
--- a/boot/README.md
+++ b/boot/README.md
@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: Apache-2.0 -->
+<!-- SPDX-License-Identifier: GPL-2.0-or-later -->
 # Booting SchOS
 One firmware path:
--- a/boot/common/ui.c
+++ b/boot/common/ui.c
@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: Apache-2.0 */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
 * The loader's user interface. See ui.h for why this can be shared at all.
 *
--- a/boot/common/ui.h
+++ b/boot/common/ui.h
@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: Apache-2.0 */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
 * The loader's user interface, shared by both firmwares.
 *
--- a/boot/uefi/README.md
+++ b/boot/uefi/README.md
@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: Apache-2.0 -->
+<!-- SPDX-License-Identifier: GPL-2.0-or-later -->
 # UEFI loader
 The loader. This directory once existed only so the BIOS path could be moved
--- a/boot/uefi/efi.h
+++ b/boot/uefi/efi.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 #pragma once
 #ifndef SCHOS_EFI_H
 #define SCHOS_EFI_H
--- a/boot/uefi/main.c
+++ b/boot/uefi/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchOS UEFI loader.
 //
--- a/cmd/chvt/main.c
+++ b/cmd/chvt/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // chvt N -- show virtual terminal N.
 //
--- a/cmd/httpd/main.c
+++ b/cmd/httpd/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // httpd -- serve a directory over HTTP.
 //
--- a/cmd/ldlsd/main.c
+++ b/cmd/ldlsd/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // ldlsd -- LDLS, on SchOS.
 //
--- a/cmd/loadkeys/main.c
+++ b/cmd/loadkeys/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // loadkeys -- choose the keyboard layout.
 //
--- a/cmd/memfdtest/main.c
+++ b/cmd/memfdtest/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // memfdtest -- two processes map the same memfd, one writes, the other sees it.
 //
--- a/cmd/netecho/main.c
+++ b/cmd/netecho/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // netecho -- a network, in a process.
 //
--- a/cmd/pcitest/main.c
+++ b/cmd/pcitest/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // pcitest -- prove that a driver could live out here.
 //
--- a/cmd/ping/main.c
+++ b/cmd/ping/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // ping -- ICMP echo, over a SchOS ping socket.
 //
--- a/cmd/resolvconf/main.c
+++ b/cmd/resolvconf/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // resolvconf -- put the nameserver where the resolver will look.
 //
--- a/cmd/schdbg/main.c
+++ b/cmd/schdbg/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // schdbg -- ask the kernel a question.
 //
--- a/cmd/schdbgd/main.c
+++ b/cmd/schdbgd/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // schdbgd -- the debugger, over the network.
 //
--- a/cmd/schinit/main.c
+++ b/cmd/schinit/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // schinit -- PID 1.
 //
--- a/cmd/schinitd/main.c
+++ b/cmd/schinitd/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // schinitd -- the supervisor. PID 2, and restartable.
 //
--- a/cmd/schmode/main.c
+++ b/cmd/schmode/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // schmode -- change the display mode.
 //
--- a/cmd/sigtest/main.c
+++ b/cmd/sigtest/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // sigtest -- the SIGCHLD/sigsuspend contract every shell is built on.
 //
--- a/cmd/vgpud/main.c
+++ b/cmd/vgpud/main.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // vgpud -- the virtio-gpu driver, outside the kernel.
 //
--- a/docs/Website/README.md
+++ b/docs/Website/README.md
@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: Apache-2.0 -->
+<!-- SPDX-License-Identifier: GPL-2.0-or-later -->
 # The website
 Three pages, two scripts, one stylesheet of its own, and the design system
--- a/docs/Website/app.css
+++ b/docs/Website/app.css
@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: Apache-2.0 */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /* ==========================================================================
   The SchOS site — layout only
   --------------------------------------------------------------------------
--- a/docs/Website/app.js
+++ b/docs/Website/app.js
@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: Apache-2.0
+/* SPDX-License-Identifier: GPL-2.0-or-later
 *
 * Three behaviours, no framework:
 *   1. the hero console types a real boot log
--- a/docs/Website/docs.html
+++ b/docs/Website/docs.html
@ -77,7 +77,7 @@
  <div class="nv-divider"></div>
  <div class="site-footer__row">
    <span class="nv-body">SchOS — kernel <b>SchIFT</b>, filesystem <b>SchFS</b>.</span>
-    <span class="nv-code nv-text-tertiary">Apache-2.0, with the xv6-derived core under MIT.</span>
+    <span class="nv-code nv-text-tertiary">GPL-2.0-or-later, with the xv6-derived core under MIT.</span>
  </div>
  <p class="nv-body nv-text-secondary pride-note" id="pride-note">
--- a/docs/Website/docs.js
+++ b/docs/Website/docs.js
@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: Apache-2.0
+/* SPDX-License-Identifier: GPL-2.0-or-later
 *
 * The documentation reader.
 *
--- a/docs/Website/download.html
+++ b/docs/Website/download.html
@ -283,7 +283,7 @@
  <div class="nv-divider"></div>
  <div class="site-footer__row">
    <span class="nv-body">SchOS — kernel <b>SchIFT</b>, filesystem <b>SchFS</b>.</span>
-    <span class="nv-code nv-text-tertiary">Apache-2.0, with the xv6-derived core under MIT.</span>
+    <span class="nv-code nv-text-tertiary">GPL-2.0-or-later, with the xv6-derived core under MIT.</span>
  </div>
  <p class="nv-body nv-text-secondary pride-note" id="pride-note">
--- a/docs/Website/index.html
+++ b/docs/Website/index.html
@ -92,7 +92,7 @@
      <a class="nv-button nv-button--lg" href="#what">What it has</a>
    </div>
-    <p class="nv-caption">Apache-2.0 · runs from RAM · writes nothing to your disks</p>
+    <p class="nv-caption">GPL-2.0-or-later · runs from RAM · writes nothing to your disks</p>
  </div>
  <div class="nv-card nv-card--flush console" aria-label="Boot log">
@ -642,7 +642,7 @@
  <div class="nv-divider"></div>
  <div class="site-footer__row">
    <span class="nv-body">SchOS — kernel <b>SchIFT</b>, filesystem <b>SchFS</b>.</span>
-    <span class="nv-code nv-text-tertiary">Apache-2.0, with the xv6-derived core under MIT.</span>
+    <span class="nv-code nv-text-tertiary">GPL-2.0-or-later, with the xv6-derived core under MIT.</span>
  </div>
  <p class="nv-body nv-text-secondary pride-note" id="pride-note">
--- a/docs/architecture/audio.md
+++ b/docs/architecture/audio.md
@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: Apache-2.0 -->
+<!-- SPDX-License-Identifier: GPL-2.0-or-later -->
 # Audio
 A program that wants to make a sound opens `/dev/dsp`, writes PCM to it, and
--- a/docs/architecture/devices.md
+++ b/docs/architecture/devices.md
@ -247,10 +247,11 @@ manager or equivalent, and SchOS will load it.
 The licensing reasoning matters and is worth stating exactly, because it is
 easy to get wrong in both directions:
- **Distribution is what triggers the GPL.** Shipping a GPL-2.0-only driver in
+- **Distribution is what triggers the GPL.** SchOS is GPL-2.0-or-later, so
-  an Apache-2.0 image is what cannot be done — see [../licensing.md](../licensing.md)
+  shipping a GPL-2.0-only driver in an image is now *possible* — see
-  §2. A user obtaining a driver themselves and loading it on their own machine
+  [../licensing.md](../licensing.md) §6 — but LDLS still does not, by policy. A
-  is their act, not ours, and is not a distribution by us.
+  user obtaining a driver themselves and loading it on their own machine is
  their act, not ours, and is not a distribution by us.
 - **Implementing a loader is not copying.** Writing support for a module format
  and a driver ABI from published documentation produces our own work. It is a
  clean-room implementation, and it stays one only if it is written from
@ -259,8 +260,8 @@ easy to get wrong in both directions:
  identifiers say.
 So the rule for this subsystem is the same as everywhere else in the tree: the
-loader is ours and Apache-2.0, what it loads is the user's business, and nothing
+loader is ours and GPL-2.0-or-later, what it loads is the user's business, and
-GPL ever enters an image we build. `RAMDISK_EXCLUDE` and `NOTPORTS` are the
+no third-party module enters an image we build. `RAMDISK_EXCLUDE` and `NOTPORTS` are the
 existing mechanisms for keeping that true mechanically rather than by intention.
 ---
--- a/docs/architecture/ldls.md
+++ b/docs/architecture/ldls.md
@ -54,9 +54,10 @@ ships the layer and never the thing it loads. `.gitignore` refuses `*.ko`,
 is deliberately not part of `all`, and `make ldls-unstage` takes it out again.
 [../licensing.md](../licensing.md) §6 is the whole argument. The short form is
-that GPL obligations attach to *distribution*, we distribute Apache-2.0 code
+that the combination happens in a user process on the user's machine, so no
-containing no GPL, and the combination happens in a user process on the user's
+combined work is distributed by anyone. Since SchOS moved to GPL-2.0-or-later
-machine — so no combined work is distributed by anyone.
+that is no longer the only way it *could* be done — it is the way it is done,
 because a module we never ship is a module we never have to answer for.
 ### 2. It runs in a process, never in the kernel
--- a/docs/architecture/terminals.md
+++ b/docs/architecture/terminals.md
@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: Apache-2.0 -->
+<!-- SPDX-License-Identifier: GPL-2.0-or-later -->
 # Virtual terminals
 Six of them, `/dev/tty1` through `/dev/tty6`.
--- a/docs/branding/README.md
+++ b/docs/branding/README.md
@ -55,7 +55,7 @@ the kernel's name (**SchIFT**) as a shape.
  coverage mask carries none, so the loader draws it in metal and the kernel in
  the theme accent, from the same bytes.
 - **With or without a wordmark.** Set "SchOS" beside it in **Roboto Bold**,
-  which is already in the tree (`ports/Roboto`), already Apache-2.0, and already
+  which is already in the tree (`ports/Roboto`), Apache-2.0, and already
  in `NOTICE`.
 - Non-human and non-animal, permanently. If a character is ever drawn it gets
  its own mark; a logo that starts growing a face has taken that job.
--- a/docs/guides/building.md
+++ b/docs/guides/building.md
@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: Apache-2.0 -->
+<!-- SPDX-License-Identifier: GPL-2.0-or-later -->
 # Building SchOS
 Supported hosts: **Linux, macOS, FreeBSD/OpenBSD/NetBSD, and Windows** (under
--- a/docs/guides/layout.md
+++ b/docs/guides/layout.md
@ -130,8 +130,8 @@ file protocol, so a 6 MB ramroot kernel is visibly slower to start than the
 **What may go in it is a licensing question, not only a size one.** The image is
 linked into the kernel binary, so anything in `sysroot/` when it is built becomes
 part of a distributable artifact. A file staged there under a licence that
-cannot be combined with Apache-2.0 does not merely ride along — it makes the
+is not ours to redistribute does not merely ride along — it makes the kernel
-kernel itself undistributable. `RAMDISK_EXCLUDE` in the Makefile is the list of
+itself undistributable. `RAMDISK_EXCLUDE` in the Makefile is the list of
 paths kept out, and enforcing it in the build rather than relying on someone
 remembering to unstage something first is deliberate. It has been needed once
 already: a 33 MB test payload landed in `sysroot/` and both overflowed the image
--- a/docs/history/moving-to-linux.md
+++ b/docs/history/moving-to-linux.md
@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: Apache-2.0 -->
+<!-- SPDX-License-Identifier: GPL-2.0-or-later -->
 # Moving the project to a Linux machine
 **This move happened.** The tree lives on Fedora now, and the checkout is at
--- a/docs/licensing.md
+++ b/docs/licensing.md
@ -7,24 +7,31 @@ pointed here long before this file existed.
 ---
-## 1. SchOS is Apache-2.0
+## 1. SchOS is GPL-2.0-or-later
-Copyright Nexoniarz. See `LICENSE`.
+Copyright Nexoniarz. See `LICENSE`. Until 2026-10 SchOS was Apache-2.0; it was
 never published under that licence, and as the sole author Nexoniarz relicensed
 it outright.
-Apache-2.0 was chosen over MIT/BSD for one reason that actually matters at OS
+**Why the GPL.** Two reasons, one about others and one about us:
 scale: it contains an **express patent grant** and a patent-retaliation clause.
 MIT and BSD are silent on patents, which means a contributor can hand you code
 and later assert a patent over it. For a kernel that is intended to accept
 outside contributions, that silence is the expensive kind.
-What that grant means in practice: Apache-2.0 §2 gives everyone a perpetual,
+- **Copyleft.** Anyone may use, study, modify and redistribute SchOS — but
-worldwide, irrevocable licence to reproduce, modify, sublicense and distribute
+  whoever ships it, or something built from it, must ship the source of that
-SchOS. Any additional restriction stated elsewhere — in a README, a website,
+  too, under the same terms. Under Apache-2.0 a fork could be closed and sold
-or a policy — does not narrow it. The licence text is what holds up.
+  with no changes given back. The GPL does not forbid commercial use; it forbids
  taking the work private.
 - **Linux.** Linux is GPL-2.0-only, and Apache-2.0 could not be combined with
  it. Under the GPL, Linux drivers and code can be adopted (§2).
-If restricted distribution is ever genuinely wanted, that is a licence change
+**Why "or later".** It keeps one door open that "only" would close: GPLv3 and
-(a bespoke proprietary licence, or something like BUSL-1.1 with a conversion
+Apache-2.0 code can still be combined with SchOS code, with that combination
-date), not a wording change, and it means giving up the Apache grant.
+shipping under GPLv3. See §2 for why the kernel should not walk through it.
 **What was given up.** Apache-2.0 had an express patent grant; GPLv2 has only
 an implied one. That mattered most for outside contributions, and there are
 none yet.
 New first-party files carry `SPDX-License-Identifier: GPL-2.0-or-later`.
 ---
@ -36,37 +43,32 @@ date), not a wording change, and it means giving up the Apache grant.
 | MIT, ISC | **Yes** | Keep the notice |
 | BSD 2-clause | **Yes** | Keep the notice |
 | BSD 3-clause | **Yes** | Keep the notice; no endorsement claims |
-| BSD **4-clause** (advertising) | **Avoid** — see §3 | Notice *and* an acknowledgement in advertising materials |
+| BSD **4-clause** (advertising) | **No** — see §3 | GPL-incompatible |
-| Apache-2.0 | **Yes** | Keep NOTICE contents |
+| GPL-2.0-only, GPL-2.0-or-later, LGPL-2.1 | **Yes** | Source for the combined work; keep the notices |
-| MPL-2.0 | Case by case | File-level copyleft; keep those files separate |
+| MPL-2.0 | Case by case | Compatible through its secondary-licence clause, unless marked otherwise |
-| **GPL-2.0-only** | **No** | — |
+| Apache-2.0, GPL-3.0, LGPL-3.0 | **Not in the kernel**; separate programs and files fine | See below |
 | **GPL-3.0 / LGPL-3.0** | **No** for linked code | — |
 **Every "yes" above requires an entry in `NOTICE`.** That file is the project's
-attribution record and the thing that makes the permissive licences actually
+attribution record and the thing that makes the licences actually satisfied
-satisfied rather than merely tolerated.
+rather than merely tolerated.
-### Why GPL-2.0-only is a hard no
+### One binary, one GPL version
-Apache-2.0 imposes conditions GPLv2 treats as "further restrictions" under its
+"Or later" means SchOS code can go out under GPLv2 *or* GPLv3. A single linked
-§6 — principally the patent-retaliation term. The FSF and the ASF agree on
+binary still has to pick one:
 this: **Apache-2.0 code and GPL-2.0-only code cannot be combined into one
 distributable work.** It is not a matter of taste or of how carefully the files
 are kept apart in the tree; it is that the combined binary cannot satisfy both
 licences at once.
-GPL-3.0 fixed this in the other direction (Apache-2.0 is compatible *into*
+- Add **Linux code** (GPL-2.0-only) and that binary is GPLv2.
-GPLv3), but that does not help: the result would have to ship under GPLv3, and
+- Add **Apache-2.0 or GPLv3 code** and that binary is GPLv3, because
-SchOS does not.
+  Apache-2.0's patent terms are "further restrictions" under GPLv2 §6.
-**Practical consequence:** BSD drivers can be adopted. Linux drivers cannot,
+Those two cannot meet in one binary. Linux is the main reason for the GPL, so
-ever, no matter how convenient. This is why the USB stack was written from the
+**the kernel stays GPLv2-compatible**: no Apache-2.0 or GPLv3 code is linked
-specification rather than ported.
+into it. Userland programs are separate works, so one may be GPLv3 or
 Apache-2.0 on its own without affecting anything else.
-**"Cannot be adopted" is not the same as "cannot be run."** A driver the *user*
+Data files such as fonts are not linked code. Roboto (Apache-2.0) sits beside
-obtains and loads on their own machine is their act, not a distribution by us —
+the system as an aggregate, and that holds inside the ramdisk too: the image is
-see §4 and [architecture/ldls.md](architecture/ldls.md), which is the layer built on exactly
+a filesystem carried by the kernel binary, not code linked with it.
 that distinction and which ships no Linux code of any kind.
 ---
@ -80,7 +82,7 @@ uniformly licensed**, and the difference matters per file:
 |---|---|
 | 2-clause BSD — modern NetBSD Foundation files | **Fine** |
 | 3-clause, "Regents of the University of California" | **Fine.** Berkeley formally rescinded the advertising clause in 1999 |
-| 4-clause with the advertising clause, **non-UC** copyright holder | **Avoid.** Berkeley's rescission covers Berkeley's copyright, not other people's |
+| 4-clause with the advertising clause, **non-UC** copyright holder | **No.** Berkeley's rescission covers Berkeley's copyright, not other people's, and the clause is GPL-incompatible |
 The last row is real, not hypothetical. Measured on this checkout:
@ -91,10 +93,9 @@ lib/libc     101 of 1575
 sys/net        5 of  180      ← the TCP/IP stack is nearly clean
 ```
-4-clause is still permissive and still redistributable; the burden is an
+4-clause is still permissive on its own, but the advertising clause is a
-advertising obligation that accumulates quietly and is tedious to honour
+further restriction the GPL does not allow, so **a 4-clause file cannot be
-properly. Prefer a 2-clause or UC-Regents file. If a 4-clause file is genuinely
+combined with SchOS at all**. Use a 2-clause or UC-Regents file, or write it.
 the right answer, it goes into `NOTICE` with the full clause quoted.
 Check before copying, not after:
@ -128,7 +129,7 @@ the top of the file; the UC block is a separate licence further down. Berkeley
 never spoke for WIDE, so the rescission does not reach it. The two most
 valuable files in the stack are the two encumbered ones.
-That is not fatal — 4-clause is still permissive — but it is exactly the case
+Under the GPL that rules them out, and it is exactly the case
 where a **second BSD tree earns its disk space**: FreeBSD's TCP has been
 through a relicensing effort NetBSD's has not, so the same file there may well
 be 2-clause. Check it the same way before assuming either:
@ -180,13 +181,13 @@ Chosen 2026-08-09, both licences checked at source rather than assumed:
 | Roboto | desktop, window manager, compositor | **Apache-2.0** |
 | JetBrains Mono | terminal, TTY | **SIL OFL 1.1** |
-Roboto is the same licence as SchOS, so it is the easy case: a NOTICE entry
+Roboto is Apache-2.0, which is fine for a font: it is a data file beside the
-and nothing else.
+system, not code linked into it (§2). A NOTICE entry and nothing else.
 OFL is permissive and bundling is precisely what it is for, with two conditions
 worth knowing before anyone subsets or converts a font:
- **The font stays under OFL** even inside an Apache-2.0 system. It does not
+- **The font stays under OFL** even inside a GPL-licensed system. It does not
  infect anything else; it just cannot be relicensed.
 - **It may not be sold on its own.** Shipping it as part of an OS is fine.
 - **Reserved Font Names.** JetBrains Mono declares *none* -- its copyright line
@ -212,42 +213,17 @@ with SchOS. Keeping the distinction sharp is what stops it eroding:
  rebuild never needs the network; not part of any image, and not all of it is
  redistributable.
-### The userland this rules out, and what was done instead
+### The userland, and why it is permissive anyway
-The rule costs something real and it is worth naming the bill rather than only
+While SchOS was Apache-2.0, **BusyBox** (GPL-2.0-only) and **nano** (GPL-3.0)
-the principle.
+were ruled out, and the userland was built from toybox (0BSD), mksh and kilo
 (BSD-2-Clause) instead. Both would be possible now — nano as a separate program
 — but nothing needs replacing: toybox gives 268 applets, kilo is installed as
 `/bin/edit`, and `cmd/httpd` is first-party.
-**BusyBox** is the obvious userland for a system this size — about four hundred
+The `wget` failure that started that discussion was not a userland problem:
-applets, including a shell, an editor, `less` and an `httpd`. It is
+SchOS had no DNS reachable from a process, which BusyBox would have hit
-**GPL-2.0-only**, so §2 applies, and here the consequence is sharper than
+identically. See [architecture/networking.md](architecture/networking.md).
 "cannot be linked": `make ramroot` links the root filesystem image *into the
 kernel binary*, so a BusyBox in `sysroot/` would put GPLv2 code inside an
 Apache-2.0 executable. Excluding it from the ramdisk avoids that and leaves the
 ramroot build with no userland at all, which is not a trade worth making.
 **nano** is the same answer for the same reason, one version later: GPL-3.0,
 which is incompatible with Apache-2.0 in the other direction.
 What was done instead, when the complaint "the userland is too thin" came up:
 | wanted | answer |
 |---|---|
 | `awk`, `bc`, `diff`, `more`, `expr`, `tr`, … | already in toybox, in `toys/pending/`, switched off by `defconfig`. Turning 26 of them on took the shipped set from 236 applets to 268, at no licensing cost — it is the same 0BSD tarball. |
 | an editor that is not `vi` | [kilo](https://github.com/antirez/kilo), BSD-2-Clause, one file, no dependencies. Installed as `/bin/edit` as well as `/bin/kilo`. |
 | `wget` that works | not a userland problem at all. See below. |
 | something to host with | `cmd/httpd`, written here, Apache-2.0. |
 The `wget` one is worth recording because it was diagnosed wrongly at first,
 and switching userland would not have fixed it: **SchOS had no DNS reachable
 from a process**, so every program taking a hostname failed and each looked
 like its own bug. BusyBox's `wget` would have failed identically. musl already
 contains a complete resolver; the only missing fact was which nameserver, which
 the kernel had all along from DHCP and never published. See
 [architecture/networking.md](architecture/networking.md).
 The general shape: **a permissive answer existed for every one of these**, and
 three of the four were already in the tree. That will not always be true, and
 when it is not the answer is still no.
 The mechanisms that keep this from eroding, since good intentions have already
 failed once here:
@ -286,22 +262,26 @@ copied file is a file to be understood, attributed and maintained forever.
 ## 6. LDLS, and the distribution boundary
-[architecture/ldls.md](architecture/ldls.md) runs Linux drivers. That sounds like it should
+[architecture/ldls.md](architecture/ldls.md) runs Linux drivers. This section
-contradict §2, and it does not, because the two questions below are different
+was written when SchOS was Apache-2.0 and the boundary below was a legal
-ones and only the first is about us.
+necessity. Under GPL-2.0-or-later it is a **project policy** instead: shipping
 a GPL-2.0-only `.ko` with SchOS would now be lawful, provided the source goes
 with it. It is still not done, because a module we never ship is a module we
 never have to vouch for, track upstream, or provide source for.
-### LDLS is Apache-2.0
+### LDLS is ours
-Every file under `ldls/` is ours. The loader was written from the ELF-64 gABI
+Every file under `ldls/` is ours, GPL-2.0-or-later. The loader was written from
-and the x86-64 psABI; the shim is written under the rule in
+the ELF-64 gABI and the x86-64 psABI; the shim is written under the rule in
-[architecture/ldls.md](architecture/ldls.md). **No Linux code is in it and none ever will
+[architecture/ldls.md](architecture/ldls.md). Copying Linux code into it would
-be**, which is the same standard the xHCI and USB stacks already meet (§5).
+no longer be a licence problem, but the shim's value is that it is small and
 understood, so the existing rule stands.
-### The combination is not ours to make
+### The combination is the user's
 | | licence | who distributes it |
 |---|---|---|
-| `ldls/` — loader, shim, host | **Apache-2.0** | us |
+| `ldls/` — loader, shim, host | **GPL-2.0-or-later** | us |
 | a `.ko` | GPL-2.0-only, usually | the user's distribution |
 | the two running together in a process | — | **nobody** |
@ -311,20 +291,10 @@ GPLv2 §0 is explicit about where its obligations attach:
 > by this License; they are outside its scope. **The act of running the Program
 > is not restricted.**
-So: we ship Apache-2.0 code containing no GPL. The user obtains a GPL module
+So: we ship LDLS and no modules. The user obtains a module from wherever they
-from wherever they get their software. The user runs them together on their own
+get their software and runs it on their own machine. `RAMDISK_EXCLUDE` and the
-machine. No combined work is distributed by anyone, and no GPL obligation is
+`*.ko` rule in `.gitignore` keep that boundary mechanical rather than
-triggered — not on us, and not on them.
+intentional.
 This is the position FreeBSD has shipped from for about a decade: a
 BSD-licensed `linuxkpi` in base, GPL `drm-kmod` installed by the user from
 ports.
 **The consequence for the user, stated plainly:** they cannot redistribute the
 combination either. An image with a `.ko` baked into it is a single work that
 would have to satisfy Apache-2.0 and GPL-2.0-only at once, which §2 explains is
 impossible. That is why `RAMDISK_EXCLUDE` exists, and why `.gitignore` refuses
 `*.ko` outright — the boundary is kept mechanically rather than by intention.
 ### `EXPORT_SYMBOL_GPL` does not apply
@ -335,7 +305,7 @@ that.
 **LDLS has no Linux symbols to gate.** `EXPORT_SYMBOL_GPL` is Linux marking
 *Linux's own* symbols, and the check it drives protects those. Every symbol
-LDLS provides is ours — reimplemented from facts, under Apache-2.0. There is no
+LDLS provides is ours — reimplemented from facts, under GPL-2.0-or-later. There is no
 gate being bypassed, because there is no Linux symbol being exposed.
 So LDLS implements no licence check. It **reads** the module's declared licence
--- a/docs/plan/wayland.md
+++ b/docs/plan/wayland.md
@ -135,10 +135,9 @@ in `NOTICE` **before** the file is committed, not after.
 | libxkbcommon | MIT |
 | xkeyboard-config | MIT |
-All Apache-2.0 compatible, all needing only a `NOTICE` entry. **Nothing here
+All GPL-2.0-or-later compatible, all needing only a `NOTICE` entry. The
-carries the GPL problem that governs drivers**, which is a pleasant change and
+Wayland ecosystem is permissively licensed almost throughout, so nothing here
-worth noticing: the Wayland ecosystem is permissively licensed almost throughout,
+raises a licensing question at all.
 and that is a genuine argument for it beyond any technical one.
 ---
--- a/include/fsstat.h
+++ b/include/fsstat.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Counters for the filesystem and block paths, read through /proc/fsstat.
 //
--- a/include/pciuser.h
+++ b/include/pciuser.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // /dev/pci -- device access from userspace.
 //
--- a/include/posix.h
+++ b/include/posix.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // SchOS — POSIX-compatibility types used by kernel syscall handlers.
 #pragma once
 #include "types.h"
--- a/include/schboot.h
+++ b/include/schboot.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 #pragma once
 #ifndef SCHBOOT_H
 #define SCHBOOT_H
--- a/include/schinit.h
+++ b/include/schinit.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // The protocol between PID 1 and the supervisor.
 //
--- a/include/vt.h
+++ b/include/vt.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Virtual terminals.
 //
--- a/kernel/arch/x86_64/watch.c
+++ b/kernel/arch/x86_64/watch.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Hardware watchpoints. docs/architecture/debugging.md milestone D4.
 //
--- a/kernel/core/klog.c
+++ b/kernel/core/klog.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // The kernel log that outlives the kernel. See include/klog.h.
 //
--- a/kernel/core/ksym.c
+++ b/kernel/core/ksym.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Naming an address.
 //
--- a/kernel/core/panic.c
+++ b/kernel/core/panic.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // PSOGM — the SchOS crash screen.
 //
--- a/kernel/core/sbuf.c
+++ b/kernel/core/sbuf.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // The bounded string builder. See include/sbuf.h for what it is and why it
 // moved out of kernel/dev/procfs.c.
--- a/kernel/dev/dbg.c
+++ b/kernel/dev/dbg.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // /dev/dbg -- asking the kernel a question. See include/dbg.h.
 //
--- a/kernel/dev/netuser.c
+++ b/kernel/dev/netuser.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // /dev/netdev -- a network interface whose backend is a process.
 // See include/netuser.h.
--- a/kernel/dev/pciuser.c
+++ b/kernel/dev/pciuser.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // /dev/pci -- PCI devices, reachable from userspace.
 //
--- a/kernel/dev/vt.c
+++ b/kernel/dev/vt.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Virtual terminals. See include/vt.h for why this exists at all; the short
 // version is that switching needs a backing store, and the console drew
--- a/kernel/drivers/bus/xhci/xhci.c
+++ b/kernel/drivers/bus/xhci/xhci.c
@ -10,9 +10,9 @@
 // the controller is not complicated; BSD is much more valuable as the
 // reference you check yourself against than as the code you paste.
 //
-// (Licensing points the same way. The BSD stacks are BSD-2/3-clause, which is
+// (Licensing no longer decides it: the BSD stacks are BSD-2/3-clause and
-// compatible with Apache-2.0 -- Linux's drivers are GPL-2.0-only, which is
+// Linux's drivers are GPL-2.0-only, and both combine with GPL-2.0-or-later.
-// not. See docs/guides/adding-a-driver.md.)
+// The argument above is the whole reason. See docs/licensing.md.)
 //
 // Enumeration polls the event ring instead of using interrupts. That is not
 // laziness: pci_bind_all() runs from kmain() with interrupts disabled and no
--- a/kernel/fs/devfs.c
+++ b/kernel/fs/devfs.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // devtmpfs: /dev, generated rather than stored.
 //
--- a/kernel/fs/schfs/attr.c
+++ b/kernel/fs/schfs/attr.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Attributes, and the index over them.
 //
--- a/kernel/fs/schfs/btree.c
+++ b/kernel/fs/schfs/btree.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchFS copy-on-write B-tree — see btree.h for the contract.
 //
--- a/kernel/fs/schfs/kmount.c
+++ b/kernel/fs/schfs/kmount.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchFS in the kernel: block device, mount, and the transaction bracket.
 //
--- a/kernel/fs/schfs/obj.c
+++ b/kernel/fs/schfs/obj.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchFS object layer, read side: inodes, directories and file data.
 //
--- a/kernel/fs/schfs/objw.c
+++ b/kernel/fs/schfs/objw.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchFS object layer, write side: create, link, unlink, rename, write,
 // truncate.
--- a/kernel/fs/schfs/schfs_int.h
+++ b/kernel/fs/schfs/schfs_int.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchFS internals: the volume (uberblock ring, block allocation) and the object
 // layer (inodes, directories, file data) that sit on top of the B-tree.
--- a/kernel/fs/schfs/space.c
+++ b/kernel/fs/schfs/space.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchFS space manager: which blocks are in use.
 //
--- a/kernel/fs/schfs/vfs.c
+++ b/kernel/fs/schfs/vfs.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchFS behind the VFS: the fs_ops table that makes SchFS files reachable
 // through open(2), read(2), write(2) and the rest.
--- a/kernel/fs/schfs/vol.c
+++ b/kernel/fs/schfs/vol.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // SchFS volume layer: the uberblock ring.
 //
--- a/kernel/net/inet.c
+++ b/kernel/net/inet.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // AF_INET sockets, on top of lwIP's raw API.
 //
--- a/kernel/net/lwip/arch/cc.h
+++ b/kernel/net/lwip/arch/cc.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // lwIP's compiler/platform header for SchOS.
 //
--- a/kernel/net/lwip/lwipopts.h
+++ b/kernel/net/lwip/lwipopts.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // lwIP configuration for SchOS.
 //
--- a/kernel/net/lwip/netif_eth.c
+++ b/kernel/net/lwip/netif_eth.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // lwIP network interfaces over the netdev class.
 //
--- a/kernel/net/lwip/shim/ctype.h
+++ b/kernel/net/lwip/shim/ctype.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // <ctype.h> for lwIP, shadowing the host's.
 //
 // Empty on purpose. Everything lwIP would take from this header is supplied by
--- a/kernel/net/lwip/shim/errno.h
+++ b/kernel/net/lwip/shim/errno.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // <errno.h> for lwIP, shadowing the host's.
 //
 // Empty on purpose. Everything lwIP would take from this header is supplied by
--- a/kernel/net/lwip/shim/inttypes.h
+++ b/kernel/net/lwip/shim/inttypes.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // <inttypes.h> for lwIP, shadowing the host's.
 //
 // Empty on purpose. Everything lwIP would take from this header is supplied by
--- a/kernel/net/lwip/shim/limits.h
+++ b/kernel/net/lwip/shim/limits.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // <limits.h> for lwIP, shadowing the host's.
 //
 // Empty on purpose. Everything lwIP would take from this header is supplied by
--- a/kernel/net/lwip/shim/stddef.h
+++ b/kernel/net/lwip/shim/stddef.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // <stddef.h> for lwIP, shadowing the host's.
 //
 // Empty on purpose. Everything lwIP would take from this header is supplied by
--- a/kernel/net/lwip/shim/stdint.h
+++ b/kernel/net/lwip/shim/stdint.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // <stdint.h> for lwIP, shadowing the host's.
 //
 // Empty on purpose. Everything lwIP would take from this header is supplied by
--- a/kernel/net/lwip/shim/stdio.h
+++ b/kernel/net/lwip/shim/stdio.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // <stdio.h> for lwIP, shadowing the host's.
 //
 // Empty on purpose. Everything lwIP would take from this header is supplied by
--- a/kernel/net/lwip/shim/stdlib.h
+++ b/kernel/net/lwip/shim/stdlib.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // <stdlib.h> for lwIP, shadowing the host's. See shim/string.h for why these
 // files exist at all.
--- a/kernel/net/lwip/shim/string.h
+++ b/kernel/net/lwip/shim/string.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // <string.h> for lwIP, shadowing the host's.
 //
--- a/kernel/net/lwip/shim/unistd.h
+++ b/kernel/net/lwip/shim/unistd.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // <unistd.h> for lwIP, shadowing the host's.
 //
 // Empty on purpose. Everything lwIP would take from this header is supplied by
--- a/kernel/net/lwip/sys_arch.c
+++ b/kernel/net/lwip/sys_arch.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // The lwIP port layer: everything lwIP needs from the system it runs on.
 //
--- a/kernel/net/net.c
+++ b/kernel/net/net.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // The network thread, and the one place the TCP/IP stack is started.
 //
--- a/kernel/net/netlink.c
+++ b/kernel/net/netlink.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // rtnetlink, enough of it that getifaddrs(3) works.
 //
--- a/kernel/sys/linux_abi.c
+++ b/kernel/sys/linux_abi.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 // Linux x86_64 syscall number -> SchOS syscall number translation.
 // Enabled per process by sys_enable_linux_abi (see kernel/sys/sys_compat.c).
 //
--- a/ldls/btf.c
+++ b/ldls/btf.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Reading BTF. See ldls/btf.h.
 //
--- a/ldls/btf.h
+++ b/ldls/btf.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Reading BTF: struct layouts and function prototypes, from the kernel that
 // the driver was built for.
--- a/ldls/host/inspect.c
+++ b/ldls/host/inspect.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // ldls-inspect -- what is in a relocatable object, and what it wants.
 //
--- a/ldls/host/run.c
+++ b/ldls/host/run.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // ldls-run -- load a module and call its init, on the build machine.
 //
--- a/ldls/host/types.c
+++ b/ldls/host/types.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // ldls-types -- ask a kernel's BTF where its fields are.
 //
--- a/ldls/ko.c
+++ b/ldls/ko.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Loading a relocatable object. See ldls/ko.h.
 //
--- a/ldls/ko.h
+++ b/ldls/ko.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 #pragma once
 // Loading a relocatable object. docs/architecture/ldls.md, "The loader".
--- a/ldls/kpi/io.c
+++ b/ldls/kpi/io.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // Register access. See ldls/kpi/kpi.h for the provenance rule.
 //
--- a/ldls/kpi/kpi.c
+++ b/ldls/kpi/kpi.c
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // The KPI, and the table the loader resolves against. See ldls/kpi/kpi.h.
 //
--- a/ldls/kpi/kpi.h
+++ b/ldls/kpi/kpi.h
@ -1,4 +1,4 @@
-// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: GPL-2.0-or-later
 //
 // The KPI: the Linux symbols a hosted driver actually calls, implemented.
 //
--- a/Show more
+++ b/Show more