linux.git/arch/um/include, branch v6.17

Merge tag 'uml-for-linux-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux

2025-07-30T03:31:45+00:00

Pull uml updates from Johannes Berg:
 "Mostly cleanups, except:

   - dynamic addition of vfio passthrough devices

   - implementation of HAVE_SYSCALL_TRACEPOINTS"

* tag 'uml-for-linux-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
  um: Replace __ASSEMBLY__ with __ASSEMBLER__ in the usermode headers
  um: Stop tracking stub's PID via userspace_pid[]
  um: Remove the pid parameter of handle_trap()
  um: Use err consistently in userspace()
  um: vfio: Support adding devices via mconsole
  um: rtc: Avoid shadowing err in uml_rtc_start()
  um: Avoid redefining ARCH_HAS_CACHE_LINE_SIZE
  um: Make mm_list and mm_list_lock static
  um: Make unscheduled_userspace_iterations static
  um: Re-evaluate thread flags repeatedly
  um: simplify syscall header files
  um/ptrace: Implement HAVE_SYSCALL_TRACEPOINTS
  um/x86: Add system call table to header file
  um: virt-pci: Switch to msi_create_parent_irq_domain()
  um: virtio_pcidev: Rename UM_PCI_STAT_WAITING

Merge tag 'pull-headers_param' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2025-07-28T16:03:37+00:00

Pull asm/param cleanup from Al Viro:
 "This massages asm/param.h to simpler and more uniform shape:

   - all arch/*/include/uapi/asm/param.h are either generated includes
     of  or a #define or two followed by such
     include

   - no arch/*/include/asm/param.h anywhere, generated or not

   - include  resolves to arch/*/include/uapi/asm/param.h
     of the architecture in question (or that of host in case of uml)

   - include/asm-generic/param.h pulls uapi/asm-generic/param.h and
     deals with USER_HZ, CLOCKS_PER_SEC and with HZ redefinition after
     that"

* tag 'pull-headers_param' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  loongarch, um, xtensa: get rid of generated arch/$ARCH/include/asm/param.h
  alpha: regularize the situation with asm/param.h
  xtensa: get rid uapi/asm/param.h

um: Replace ASSEMBLY with ASSEMBLER in the usermode headers

2025-07-22T15:12:45+00:00

While the GCC and Clang compilers already define __ASSEMBLER__
automatically when compiling assembly code, __ASSEMBLY__ is a
macro that only gets defined by the Makefiles in the kernel.
This can be very confusing when switching between userspace
and kernelspace coding, so let's standardize on the __ASSEMBLER__
macro that is provided by the compilers now.

This is a completely mechanical patch (done with a simple "sed -i"
statement).

Cc: Richard Weinberger 
Cc: Anton Ivanov 
Cc: Johannes Berg 
Cc: linux-um@lists.infradead.org
Signed-off-by: Thomas Huth 
Link: https://patch.msgid.link/20250314071013.1575167-36-thuth@redhat.com
Signed-off-by: Johannes Berg

um: Stop tracking stub's PID via userspace_pid[]

2025-07-13T17:42:49+00:00

The PID of the stub process can be obtained from current_mm_id().
There is no need to track it via userspace_pid[]. Stop doing that
to simplify the code.

Signed-off-by: Tiwei Bie 
Link: https://patch.msgid.link/20250711065021.2535362-4-tiwei.bie@linux.dev
Signed-off-by: Johannes Berg

um: Re-evaluate thread flags repeatedly

2025-07-11T06:49:02+00:00

The thread flags may change during their processing.
For example a task_work can queue a new signal to be sent.
This signal should be delivered before returning to usespace again.

Evaluate the flags repeatedly similar to other architectures.

Signed-off-by: Thomas Weißschuh 
Reviewed-by: Nam Cao 
Link: https://patch.msgid.link/20250704-uml-thread_flags-v1-1-0e293fd8d627@linutronix.de
Signed-off-by: Johannes Berg

um/ptrace: Implement HAVE_SYSCALL_TRACEPOINTS

2025-07-11T06:49:02+00:00

Implement syscall tracepoints through the generic tracing infrastructure.

Signed-off-by: Thomas Weißschuh 
Reviewed-by: Nam Cao 
Link: https://patch.msgid.link/20250703-uml-have_syscall_tracepoints-v1-2-23c1d3808578@linutronix.de
Signed-off-by: Johannes Berg

loongarch, um, xtensa: get rid of generated arch/$ARCH/include/asm/param.h

2025-06-25T02:02:05+00:00

For loongarch and xtensa that gets them to do what x86 et.al. are
doing - have asm/param.h resolve to uapi variant, which is generated
by mandatory-y += param.h and contains exact same include.

On um it will resolve to x86 uapi variant instead, which also contains
the same include (um doesn't have uapi headers, but it does build the
host ones).

Reviewed-by: Arnd Bergmann 
Signed-off-by: Al Viro

mm: pgtable: fix pte_swp_exclusive

2025-06-11T21:52:08+00:00

Make pte_swp_exclusive return bool instead of int.  This will better
reflect how pte_swp_exclusive is actually used in the code.

This fixes swap/swapoff problems on Alpha due pte_swp_exclusive not
returning correct values when _PAGE_SWP_EXCLUSIVE bit resides in upper
32-bits of PTE (like on alpha).

Suggested-by: Al Viro 
Signed-off-by: Magnus Lindholm 
Cc: Sam James 
Link: https://lore.kernel.org/lkml/20250218175735.19882-2-linmag7@gmail.com/
Link: https://lore.kernel.org/lkml/20250602041118.GA2675383@ZenIV/
[ Applied as the 'sed' script Al suggested   - Linus ]
Signed-off-by: Linus Torvalds

Merge tag 'uml-for-linux-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux

2025-06-05T18:45:33+00:00

Pull UML updates from Johannes Berg:
 "The only really new thing is the long-standing seccomp work
  (originally from 2021!). Wven if it still isn't enabled by default due
  to security concerns it can still be used e.g. for tests.

   - remove obsolete network transports

   - remove PCI IO port support

   - start adding seccomp-based process handling instead of ptrace"

* tag 'uml-for-linux-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: (29 commits)
  um: remove "extern" from implementation of sigchld_handler
  um: fix unused variable warning
  um: fix SECCOMP 32bit xstate register restore
  um: pass FD for memory operations when needed
  um: Add SECCOMP support detection and initialization
  um: Implement kernel side of SECCOMP based process handling
  um: Track userspace children dying in SECCOMP mode
  um: Add helper functions to get/set state for SECCOMP
  um: Add stub side of SECCOMP/futex based process handling
  um: Move faultinfo extraction into userspace routine
  um: vector: Use mac_pton() for MAC address parsing
  um: vector: Clean up and modernize log messages
  um: chan_kern: use raw spinlock for irqs_to_free_lock
  MAINTAINERS: remove obsolete file entry in TUN/TAP DRIVER
  um: Fix tgkill compile error on old host OSes
  um: stop using PCI port I/O
  um: Remove legacy network transport infrastructure
  um: vector: Eliminate the dependency on uml_net
  um: Remove obsolete legacy network transports
  um/asm: Replace "REP; NOP" with PAUSE mnemonic
  ...

um: pass FD for memory operations when needed

2025-06-02T14:20:10+00:00

Instead of always sharing the FDs with the userspace process, only hand
over the FDs needed for mmap when required. The idea is that userspace
might be able to force the stub into executing an mmap syscall, however,
it will not be able to manipulate the control flow sufficiently to have
access to an FD that would allow mapping arbitrary memory.

Security wise, we need to be sure that only the expected syscalls are
executed after the kernel sends FDs through the socket. This is
currently not the case, as userspace can trivially jump to the
rt_sigreturn syscall instruction to execute any syscall that the stub is
permitted to do. With this, it can trick the kernel to send the FD,
which in turn allows userspace to freely map any physical memory.

As such, this is currently *not* secure. However, in principle the
approach should be fine with a more strict SECCOMP filter and a careful
review of the stub control flow (as userspace can prepare a stack). With
some care, it is likely possible to extend the security model to SMP if
desired.

Signed-off-by: Benjamin Berg 
Link: https://patch.msgid.link/20250602130052.545733-8-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg