issues: the kernel-is-small track's input steps and exits deliver to the owner of input over the input port, and step 10's exit checks the kernel's streams deleted

issues/the-kernel-is-small-interrupts-post-and-threads-wait.md

@@ -179,15 +179,27 @@ Beside that order, each waiting on something outside it:
 
       Each half measures the kernel's lines and its longest interrupts-off
       and preemption-off windows, by stage 6 step 2's rule.
-   10. **usbd**, stage 5's second half: the whole xHCI moves, HID to the
-       keyboard claim and mass storage over `toyos-blockring`. A USB
-       keyboard's transitions reach the kernel only as usbd's keyboard claim.
+   10. **usbd**, stage 5's second half: the whole xHCI moves, HID delivered
+       to the owner of input over the `input` port and mass storage over
+       `toyos-blockring`. A USB keyboard's transitions never reach the
+       kernel, whose keyboard and mouse streams go when their last kernel
+       source leaves (the ruling on #899, applied to usbd on #901). It
+       depends on stage 7 step 2 landing first, because at step 10 usbd's
+       is the kernel's last input source (the ruling on #904,
+       https://github.com/ToyOSOrg/ToyOS/pull/904#issuecomment-6139079945).
        Its decoders are `toyos-xhci`'s Bulk-Only and SCSI modules and
        `toyos-usbhid`. **Exit**: the kernel's part, usbd's claims handed
        over again at its death: the controller's by `usbd_drives_the_spare`
        on the default `qemu-xhci` (below) and
-       `usbd_drives_the_type_c_controller`, the keyboard's by stage 7 step
-       2's kernel test on usbd's claim. usbd's, a device that stops answering
+       `usbd_drives_the_type_c_controller`; there is no keyboard claim. The
+       kernel's input streams, deleted: `keyboard.rs`, `mouse.rs` and
+       `input_merge_test.rs` gone from `kernel/src`, and no `Keyboard` or
+       `Mouse` in `sdk/abi`'s `DeviceType` or `FileType`. The
+       owner of input's, a key usbd held at its death released:
+       `toyos-input`'s test that a connection's end releases every device it
+       carried and a `gone` only its own `source`, red with `Merge`'s release
+       on a connection's end removed, and red with `gone` releasing its whole
+       connection. usbd's, a device that stops answering
        costing only itself: `toyos-xhci-sim`'s
        `a_controller_that_never_answers_still_releases_the_port`,
        `a_recovery_the_controller_refuses_lets_the_device_go` and
@@ -305,19 +317,23 @@ Beside that order, each waiting on something outside it:
    **Partly done**: step 1.
    1. **The panic console takes no input, and an `isa` claim grants a process
       exact ports and its ISA lines.** **Done** (#592).
-   2. **ps2server**, the server over that claim, feeding the kernel's keyboard
-      and mouse streams so the merge with USB HID stays where it is; the
+   2. **ps2server**, the server over that claim, delivering to the owner
+      of input over the `input` port, where userland merges it with USB HID
+      (the ruling on #899); the kernel's merge (`HELD`, `merged_buttons`,
+      `SOURCE_EXISTS`) is deleted, and its streams carry its own sources'
+      records unmerged until usbd takes the last of them; the
       kernel's driver, its vector, its actuators and the
-      `keyboard_controller` seam deleted. A keyboard claim is refused while no
-      source exists, which the supervisor's order of endowment then decides.
+      `keyboard_controller` seam deleted. ps2server's one kernel claim is the
+      `isa` row; it takes no keyboard claim, and the owner reads its
+      transitions from its `input` acceptor's connections.
       **Exit**: no i8042 code in the kernel (`arch/x86_64/i8042/`,
       `arch/x86_64/idt/i8042.rs` and both architectures'
       `keyboard_controller` gone from `kernel/src`, and `toyos-ps2`, whose
       one kernel user is `kernel/src/arch/x86_64/i8042/mod.rs`, gone from
-      `kernel/Cargo.toml`); a kernel test this step owes, that a keyboard
-      claim whose holder dies is handed to the next claimant and the
-      keyboard stream delivers its transitions and none of the dead
-      holder's, red on a kernel that keeps the dead holder as the source;
+      `kernel/Cargo.toml`); a kernel test this step owes, that the `isa`
+      row whose holder dies is handed to the next claimant with none of the
+      dead holder's records pending (`isa_lines_reach_their_holder`), red
+      on a kernel whose release keeps the dead holder's record;
       and ps2server's restart mid-packet held by `toyos-ps2`'s
       `a_lost_scancode_byte_never_wedges_the_prefix_state` and
       `a_stream_truncated_at_any_offset_resyncs_within_two_packets`.