This is a series of patches of nommu arch addition to UML. It would be nice to ask comments/opinions on this.
There are still several limitations/issues which we already found; here is the list of those issues. - memory mapped by loadable modules are not distinguished from userspace memory. -- Hajime v4: - add arch/um/nommu, arch/x86/um/nommu to contain !MMU specific codes - remove zpoline patch - drop binfmt_elf_fdpic patch - reduce ifndef CONFIG_MMU if possible - split to elf header cleanup patch [01/13] - fix kernel test robot warnings [06/13] - fix coding styles [07/13] - move task_top_of_stack definition [05/13] v3: - https://lore.kernel.org/linux-um/cover.1733199769.git.thehaj...@gmail.com/ - add seccomp-based syscall hook in addition to zpoline [06/13] - remove RFC, add a line to MAINTAINERS file - fix kernel test robot warnings [02/13,08/13,10/13] - add base-commit tag to cover letter - pull the latest uml/next - clean up SIGSEGV handling [10/13] - detect fsgsbase availability with elf aux vector [08/13] - simplify vdso code with macros [09/13] RFC v2: - https://lore.kernel.org/linux-um/cover.1731290567.git.thehaj...@gmail.com/ - base branch is now uml/linux.git instead of torvalds/linux.git. - reorganize the patch series to clean up - fixed various coding styles issues - clean up exec code path [07/13] - fixed the crash/SIGSEGV case on userspace programs [10/13] - add seccomp filter to limit syscall caller address [06/13] - detect fsgsbase availability with sigsetjmp/siglongjmp [08/13] - removes unrelated changes - removes unneeded ifndef CONFIG_MMU - convert UML_CONFIG_MMU to CONFIG_MMU as using uml/linux.git - proposed a patch of maple-tree issue (resolving a limitation in RFC v1) https://lore.kernel.org/linux-mm/20241108222834.3625217-1-thehaj...@gmail.com/ RFC: - https://lore.kernel.org/linux-um/cover.1729770373.git.thehaj...@gmail.com/ Hajime Tazaki (13): x86/um: clean up elf specific definitions x86/um: nommu: elf loader for fdpic um: decouple MMU specific code from the common part um: nommu: memory handling x86/um: nommu: syscall handling um: nommu: seccomp syscalls hook x86/um: nommu: process/thread handling um: nommu: configure fs register on host syscall invocation x86/um/vdso: nommu: vdso memory update x86/um: nommu: signal handling um: change machine name for uname output um: nommu: add documentation of nommu UML um: nommu: plug nommu code into build system Documentation/virt/uml/nommu-uml.rst | 177 ++++++++++++++++++++++ MAINTAINERS | 1 + arch/um/Kconfig | 14 +- arch/um/Makefile | 10 ++ arch/um/configs/x86_64_nommu_defconfig | 64 ++++++++ arch/um/include/asm/Kbuild | 1 + arch/um/include/asm/futex.h | 4 + arch/um/include/asm/mmu.h | 8 + arch/um/include/asm/mmu_context.h | 2 + arch/um/include/asm/ptrace-generic.h | 6 + arch/um/include/asm/uaccess.h | 7 +- arch/um/include/shared/kern_util.h | 8 + arch/um/include/shared/mem.h | 8 + arch/um/include/shared/os.h | 16 ++ arch/um/kernel/Makefile | 5 +- arch/um/kernel/mem-pgtable.c | 175 ++++++++++++++++++++++ arch/um/kernel/mem.c | 152 +------------------ arch/um/kernel/process.c | 25 ++++ arch/um/kernel/skas/process.c | 27 ---- arch/um/kernel/um_arch.c | 3 + arch/um/nommu/Makefile | 3 + arch/um/nommu/os-Linux/Makefile | 7 + arch/um/nommu/os-Linux/signal.c | 15 ++ arch/um/nommu/trap.c | 188 ++++++++++++++++++++++++ arch/um/os-Linux/Makefile | 8 +- arch/um/os-Linux/internal.h | 5 + arch/um/os-Linux/mem.c | 4 + arch/um/os-Linux/process.c | 149 ++++++++++++++++++- arch/um/os-Linux/seccomp.c | 87 +++++++++++ arch/um/os-Linux/signal.c | 12 ++ arch/um/os-Linux/skas/process.c | 132 ----------------- arch/um/os-Linux/start_up.c | 20 +++ arch/um/os-Linux/util.c | 3 +- arch/x86/um/Makefile | 7 +- arch/x86/um/asm/elf.h | 8 +- arch/x86/um/asm/module.h | 24 --- arch/x86/um/nommu/Makefile | 8 + arch/x86/um/nommu/do_syscall_64.c | 100 +++++++++++++ arch/x86/um/nommu/entry_64.S | 111 ++++++++++++++ arch/x86/um/nommu/os-Linux/Makefile | 6 + arch/x86/um/nommu/os-Linux/mcontext.c | 26 ++++ arch/x86/um/nommu/process.c | 35 +++++ arch/x86/um/nommu/signal.c | 43 ++++++ arch/x86/um/nommu/syscalls.h | 16 ++ arch/x86/um/nommu/syscalls_64.c | 115 +++++++++++++++ arch/x86/um/shared/sysdep/mcontext.h | 4 + arch/x86/um/shared/sysdep/signal.h | 22 +++ arch/x86/um/shared/sysdep/syscalls_64.h | 7 + arch/x86/um/signal.c | 17 ++- arch/x86/um/vdso/vma.c | 17 ++- fs/Kconfig.binfmt | 2 +- 51 files changed, 1564 insertions(+), 350 deletions(-) create mode 100644 Documentation/virt/uml/nommu-uml.rst create mode 100644 arch/um/configs/x86_64_nommu_defconfig create mode 100644 arch/um/kernel/mem-pgtable.c create mode 100644 arch/um/nommu/Makefile create mode 100644 arch/um/nommu/os-Linux/Makefile create mode 100644 arch/um/nommu/os-Linux/signal.c create mode 100644 arch/um/nommu/trap.c create mode 100644 arch/um/os-Linux/seccomp.c delete mode 100644 arch/x86/um/asm/module.h create mode 100644 arch/x86/um/nommu/Makefile create mode 100644 arch/x86/um/nommu/do_syscall_64.c create mode 100644 arch/x86/um/nommu/entry_64.S create mode 100644 arch/x86/um/nommu/os-Linux/Makefile create mode 100644 arch/x86/um/nommu/os-Linux/mcontext.c create mode 100644 arch/x86/um/nommu/process.c create mode 100644 arch/x86/um/nommu/signal.c create mode 100644 arch/x86/um/nommu/syscalls.h create mode 100644 arch/x86/um/nommu/syscalls_64.c create mode 100644 arch/x86/um/shared/sysdep/signal.h base-commit: bed2cc482600296fe04edbc38005ba2851449c10 -- 2.43.0
