Merge tag 'uml-for-linus-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux

Pull UML updates from Richard Weinberger:

 - Removal of dead code (TT mode leftovers, etc)

 - Fixes for the network vector driver

 - Fixes for time-travel mode

* tag 'uml-for-linus-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
  um: fix time-travel syscall scheduling hack
  um: Remove outdated asm/sysrq.h header
  um: Remove the declaration of user_thread function
  um: Remove the call to SUBARCH_EXECVE1 macro
  um: Remove unused mm_fd field from mm_id
  um: Remove unused fields from thread_struct
  um: Remove the redundant newpage check in update_pte_range
  um: Remove unused kpte_clear_flush macro
  um: Remove obsoleted declaration for execute_syscall_skas
  user_mode_linux_howto_v2: add VDE vector support in doc
  vector_user: add VDE support
  um: remove ARCH_NO_PREEMPT_DYNAMIC
  um: vector: Fix NAPI budget handling
  um: vector: Replace locks guarding queue depth with atomics
  um: remove variable stack array in os_rcv_fd_msg()

Author: torvalds

Documentation/virt/uml/user_mode_linux_howto_v2.rst

@@ -217,6 +217,8 @@ remote UML and other VM instances.
 +-----------+--------+------------------------------------+------------+
 | fd        | vector | dependent on fd type               | varies     |
 +-----------+--------+------------------------------------+------------+
+| vde       | vector | dep. on VDE VPN: Virt.Net Locator  | varies     |
++-----------+--------+------------------------------------+------------+
 | tuntap    | legacy | none                               | ~ 500Mbit  |
 +-----------+--------+------------------------------------+------------+
 | daemon    | legacy | none                               | ~ 450Mbit  |
@@ -573,6 +575,41 @@ https://github.com/NetSys/bess/wiki/Built-In-Modules-and-Ports
 
 BESS transport does not require any special privileges.
 
+VDE vector transport
+--------------------
+
+Virtual Distributed Ethernet (VDE) is a project whose main goal is to provide a
+highly flexible support for virtual networking.
+
+http://wiki.virtualsquare.org/#/tutorials/vdebasics
+
+Common usages of VDE include fast prototyping and teaching.
+
+Examples:
+
+   ``vecX:transport=vde,vnl=tap://tap0``
+
+use tap0
+
+   ``vecX:transport=vde,vnl=slirp://``
+
+use slirp
+
+   ``vec0:transport=vde,vnl=vde:///tmp/switch``
+
+connect to a vde switch
+
+   ``vecX:transport=\"vde,vnl=cmd://ssh remote.host //tmp/sshlirp\"``
+
+connect to a remote slirp (instant VPN: convert ssh to VPN, it uses sshlirp)
+https://github.com/virtualsquare/sshlirp
+
+   ``vec0:transport=vde,vnl=vxvde://234.0.0.1``
+
+connect to a local area cloud (all the UML nodes using the same
+multicast address running on hosts in the same multicast domain (LAN)
+will be automagically connected together to a virtual LAN.
+
 Configuring Legacy transports
 =============================
 

arch/um/Kconfig

@@ -11,7 +11,6 @@ config UML
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_STRNCPY_FROM_USER
 	select ARCH_HAS_STRNLEN_USER
-	select ARCH_NO_PREEMPT_DYNAMIC
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_KASAN if X86_64
 	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN