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.
- prompt configured with /etc/profile is broken (variables are not
expanded, ${HOSTNAME%%.*}:$PWD#)
- there are no mechanism implemented to cache for mapped memory of
exec(2) thus, always read files from filesystem upon every exec,
which makes slow on some benchmark (lmbench).
-- Hajime
RFC v2:
- 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):
fs: binfmt_elf_efpic: add architecture hook elf_arch_finalize_exec
x86/um: nommu: elf loader for fdpic
um: nommu: memory handling
x86/um: nommu: syscall handling
x86/um: nommu: syscall translation by zpoline
um: nommu: prevent host syscalls from userspace by seccomp filter
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 | 221 +++++++++++++++++++++++
arch/um/Kconfig | 14 +-
arch/um/Makefile | 6 +
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 | 13 +-
arch/um/include/asm/ptrace-generic.h | 6 +
arch/um/include/asm/tlbflush.h | 22 +++
arch/um/include/asm/uaccess.h | 7 +-
arch/um/include/shared/kern_util.h | 3 +
arch/um/include/shared/os.h | 14 ++
arch/um/kernel/Makefile | 3 +-
arch/um/kernel/mem.c | 12 +-
arch/um/kernel/physmem.c | 6 +
arch/um/kernel/process.c | 33 +++-
arch/um/kernel/skas/Makefile | 4 +-
arch/um/kernel/trap.c | 14 ++
arch/um/kernel/um_arch.c | 4 +
arch/um/os-Linux/Makefile | 5 +-
arch/um/os-Linux/cpu.c | 50 ++++++
arch/um/os-Linux/internal.h | 5 +
arch/um/os-Linux/main.c | 5 +
arch/um/os-Linux/process.c | 94 +++++++++-
arch/um/os-Linux/signal.c | 18 +-
arch/um/os-Linux/skas/process.c | 4 +
arch/um/os-Linux/start_up.c | 3 +
arch/um/os-Linux/util.c | 3 +-
arch/x86/um/Makefile | 18 ++
arch/x86/um/asm/elf.h | 11 +-
arch/x86/um/asm/module.h | 24 ---
arch/x86/um/asm/processor.h | 12 ++
arch/x86/um/do_syscall_64.c | 108 ++++++++++++
arch/x86/um/entry_64.S | 108 ++++++++++++
arch/x86/um/shared/sysdep/syscalls_64.h | 6 +
arch/x86/um/signal.c | 37 +++-
arch/x86/um/syscalls_64.c | 69 ++++++++
arch/x86/um/vdso/um_vdso.c | 20 +++
arch/x86/um/vdso/vma.c | 14 ++
arch/x86/um/zpoline.c | 223 ++++++++++++++++++++++++
fs/Kconfig.binfmt | 2 +-
fs/binfmt_elf_fdpic.c | 10 ++
43 files changed, 1262 insertions(+), 46 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/os-Linux/cpu.c
delete mode 100644 arch/x86/um/asm/module.h
create mode 100644 arch/x86/um/do_syscall_64.c
create mode 100644 arch/x86/um/entry_64.S
create mode 100644 arch/x86/um/zpoline.c
--
2.43.0
