1. 13 1月, 2012 2 次提交
  2. 02 11月, 2011 1 次提交
  3. 01 11月, 2011 1 次提交
  4. 15 9月, 2011 1 次提交
  5. 26 7月, 2011 1 次提交
  6. 27 5月, 2011 1 次提交
  7. 24 5月, 2011 1 次提交
  8. 15 4月, 2011 1 次提交
  9. 09 3月, 2011 1 次提交
  10. 01 3月, 2011 1 次提交
  11. 23 10月, 2008 2 次提交
  12. 07 9月, 2008 2 次提交
  13. 27 4月, 2008 3 次提交
  14. 17 4月, 2008 1 次提交
  15. 09 2月, 2008 2 次提交
    • J
      uml: runtime host VMSPLIT detection · 536788fe
      Jeff Dike 提交于
      Calculate TASK_SIZE at run-time by figuring out the host's VMSPLIT - this is
      needed on i386 if UML is to run on hosts with varying VMSPLITs without
      recompilation.
      
      TASK_SIZE is now defined in terms of a variable, task_size.  This gets rid of
      an include of pgtable.h from processor.h, which can cause include loops.
      
      On i386, task_size is calculated early in boot by probing the address space in
      a binary search to figure out where the boundary between usable and non-usable
      memory is.  This tries to make sure that a page that is considered to be in
      userspace is, or can be made, read-write.  I'm concerned about a system-global
      VDSO page in kernel memory being hit and considered to be a userspace page.
      
      On x86_64, task_size is just the old value of CONFIG_TOP_ADDR.
      
      A bunch of config variable are gone now.  CONFIG_TOP_ADDR is directly replaced
      by TASK_SIZE.  NEST_LEVEL is gone since the relocation of the stubs makes it
      irrelevant.  All the HOST_VMSPLIT stuff is gone.  All references to these in
      arch/um/Makefile are also gone.
      
      I noticed and fixed a missing extern in os.h when adding os_get_task_size.
      
      Note: This has been revised to fix the 32-bit UML on 64-bit host bug that
      Miklos ran into.
      Signed-off-by: NJeff Dike <jdike@linux.intel.com>
      Cc: Miklos Szeredi <miklos@szeredi.hu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      536788fe
    • D
      aout: mark arches that support A.OUT format · b0b933c0
      David Howells 提交于
      Mark arches that support A.OUT format by including the following in their
      master Kconfig files:
      
      	config ARCH_SUPPORTS_AOUT
      		def_bool y
      
      This should also be set if the arch provides compatibility A.OUT support for
      an older arch, for instance x86_64 for i386 or sparc64 for sparc.
      
      I've guessed at which arches don't, based on comments in the code, however I'm
      sure that some of the ones I've marked as 'yes' actually should be 'no'.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Cc: <linux-arch@vger.kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b0b933c0
  16. 04 12月, 2007 1 次提交
  17. 29 10月, 2007 1 次提交
  18. 17 10月, 2007 1 次提交
    • J
      uml: fix stub address calculations · 54ae36f2
      Jeff Dike 提交于
      The calculation of CONFIG_STUB_CODE and CONFIG_STUB_DATA didn't take into
      account anything but 3G/1G and 2G/2G, leaving the other vmsplits out in the
      cold.
      
      I'd rather not duplicate the four known host vmsplit cases for each of these
      symbols.  I'd also like to calculate them based on the highest userspace
      address.
      
      The Kconfig language seems not to allow calculation of hex constants, so I
      moved this to as-layout.h.  CONFIG_STUB_CODE, CONFIG_STUB_DATA, and
      CONFIG_STUB_START are now gone.  In their place are STUB_CODE, STUB_DATA, and
      STUB_START in as-layout.h.
      
      i386 and x86_64 seem to differ as to whether an unadorned constant is an int
      or a long, so I cast them to unsigned long so they can be printed
      consistently.  However, they are also used in stub.S, where C types don't work
      so well.  So, there are ASM_ versions of these constants for use in stub.S.  I
      also ifdef-ed the non-asm-friendly portion of as-layout.h.
      
      With this in place, most of the rest of this patch is changing CONFIG_STUB_*
      to STUB_*, except in stub.S, where they are changed to ASM_STUB_*.
      
      defconfig has the old symbols deleted.
      
      I also print these addresses out in case there is any problem mapping them on
      the host.
      
      The two stub.S files had some trailing whitespace, so that is cleaned up here.
      
      [akpm@linux-foundation.org: coding-style fixes]
      Signed-off-by: NJeff Dike <jdike@linux.intel.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      54ae36f2
  19. 31 1月, 2007 1 次提交
  20. 27 1月, 2007 1 次提交
  21. 12 10月, 2006 1 次提交
  22. 02 5月, 2006 1 次提交
  23. 27 3月, 2006 1 次提交
  24. 19 1月, 2006 1 次提交
    • P
      [PATCH] uml: arch Kconfig menu cleanups · ce2d2aed
      Paolo 'Blaisorblade' Giarrusso 提交于
      *) mark as "EXPERIMENTAL" various items that either aren't very stable or
         that are actively crashing the setup of users which don't really need them
         (i.e.  HIGHMEM and 3-level pagetables on x86 - nobody needs either,
         everybody reports "I'm using it and getting trouble").
      
      *) move net/Kconfig near to the rest of network configurations, and
         drivers/block/Kconfig near "Block layer" submenu.
      
      *) it's useless and doesn't work well to force NETDEVICES on and to disable
         the prompt like it's done.  Better remove the attempt, and change that to a
         simple "default y if UML".
      
      *) drop the warning about "report problems about HPPFS" - it's redundant
         anyway, as that's the usual procedure, and HPPFS users are especially
         technical (i.e.  they know reporting bugs is _good_).
      Signed-off-by: NPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
      Cc: Jeff Dike <jdike@addtoit.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      ce2d2aed
  25. 14 11月, 2005 1 次提交
  26. 18 9月, 2005 1 次提交
  27. 05 9月, 2005 2 次提交
  28. 08 7月, 2005 1 次提交
    • J
      [PATCH] uml: skas0 - separate kernel address space on stock hosts · d67b569f
      Jeff Dike 提交于
      UML has had two modes of operation - an insecure, slow mode (tt mode) in
      which the kernel is mapped into every process address space which requires
      no host kernel modifications, and a secure, faster mode (skas mode) in
      which the UML kernel is in a separate host address space, which requires a
      patch to the host kernel.
      
      This patch implements something very close to skas mode for hosts which
      don't support skas - I'm calling this skas0.  It provides the security of
      the skas host patch, and some of the performance gains.
      
      The two main things that are provided by the skas patch, /proc/mm and
      PTRACE_FAULTINFO, are implemented in a way that require no host patch.
      
      For the remote address space changing stuff (mmap, munmap, and mprotect),
      we set aside two pages in the process above its stack, one of which
      contains a little bit of code which can call mmap et al.
      
      To update the address space, the system call information (system call
      number and arguments) are written to the stub page above the code.  The
      %esp is set to the beginning of the data, the %eip is set the the start of
      the stub, and it repeatedly pops the information into its registers and
      makes the system call until it sees a system call number of zero.  This is
      to amortize the cost of the context switch across multiple address space
      updates.
      
      When the updates are done, it SIGSTOPs itself, and the kernel process
      continues what it was doing.
      
      For a PTRACE_FAULTINFO replacement, we set up a SIGSEGV handler in the
      child, and let it handle segfaults rather than nullifying them.  The
      handler is in the same page as the mmap stub.  The second page is used as
      the stack.  The handler reads cr2 and err from the sigcontext, sticks them
      at the base of the stack in a faultinfo struct, and SIGSTOPs itself.  The
      kernel then reads the faultinfo and handles the fault.
      
      A complication on x86_64 is that this involves resetting the registers to
      the segfault values when the process is inside the kill system call.  This
      breaks on x86_64 because %rcx will contain %rip because you tell SYSRET
      where to return to by putting the value in %rcx.  So, this corrupts $rcx on
      return from the segfault.  To work around this, I added an
      arch_finish_segv, which on x86 does nothing, but which on x86_64 ptraces
      the child back through the sigreturn.  This causes %rcx to be restored by
      sigreturn and avoids the corruption.  Ultimately, I think I will replace
      this with the trick of having it send itself a blocked signal which will be
      unblocked by the sigreturn.  This will allow it to be stopped just after
      the sigreturn, and PTRACE_SYSCALLed without all the back-and-forth of
      PTRACE_SYSCALLing it through sigreturn.
      
      This runs on a stock host, so theoretically (and hopefully), tt mode isn't
      needed any more.  We need to make sure that this is better in every way
      than tt mode, though.  I'm concerned about the speed of address space
      updates and page fault handling, since they involve extra round-trips to
      the child.  We can amortize the round-trip cost for large address space
      updates by writing all of the operations to the data page and having the
      child execute them all at the same time.  This will help fork and exec, but
      not page faults, since they involve only one page.
      
      I can't think of any way to help page faults, except to add something like
      PTRACE_FAULTINFO to the host.  There is PTRACE_SIGINFO, but UML doesn't use
      siginfo for SIGSEGV (or anything else) because there isn't enough
      information in the siginfo struct to handle page faults (the faulting
      operation type is missing).  Adding that would make PTRACE_SIGINFO a usable
      equivalent to PTRACE_FAULTINFO.
      
      As for the code itself:
      
      - The system call stub is in arch/um/kernel/sys-$(SUBARCH)/stub.S.  It is
        put in its own section of the binary along with stub_segv_handler in
        arch/um/kernel/skas/process.c.  This is manipulated with run_syscall_stub
        in arch/um/kernel/skas/mem_user.c.  syscall_stub will execute any system
        call at all, but it's only used for mmap, munmap, and mprotect.
      
      - The x86_64 stub calls sigreturn by hand rather than allowing the normal
        sigreturn to happen, because the normal sigreturn is a SA_RESTORER in
        UML's address space provided by libc.  Needless to say, this is not
        available in the child's address space.  Also, it does a couple of odd
        pops before that which restore the stack to the state it was in at the
        time the signal handler was called.
      
      - There is a new field in the arch mmu_context, which is now a union.
        This is the pid to be manipulated rather than the /proc/mm file
        descriptor.  Code which deals with this now checks proc_mm to see whether
        it should use the usual skas code or the new code.
      
      - userspace_tramp is now used to create a new host process for every UML
        process, rather than one per UML processor.  It checks proc_mm and
        ptrace_faultinfo to decide whether to map in the pages above its stack.
      
      - start_userspace now makes CLONE_VM conditional on proc_mm since we need
        separate address spaces now.
      
      - switch_mm_skas now just sets userspace_pid[0] to the new pid rather
        than PTRACE_SWITCH_MM.  There is an addition to userspace which updates
        its idea of the pid being manipulated each time around the loop.  This is
        important on exec, when the pid will change underneath userspace().
      
      - The stub page has a pte, but it can't be mapped in using tlb_flush
        because it is part of tlb_flush.  This is why it's required for it to be
        mapped in by userspace_tramp.
      
      Other random things:
      
      - The stub section in uml.lds.S is page aligned.  This page is written
        out to the backing vm file in setup_physmem because it is mapped from
        there into user processes.
      
      - There's some confusion with TASK_SIZE now that there are a couple of
        extra pages that the process can't use.  TASK_SIZE is considered by the
        elf code to be the usable process memory, which is reasonable, so it is
        decreased by two pages.  This confuses the definition of
        USER_PGDS_IN_LAST_PML4, making it too small because of the rounding down
        of the uneven division.  So we round it to the nearest PGDIR_SIZE rather
        than the lower one.
      
      - I added a missing PT_SYSCALL_ARG6_OFFSET macro.
      
      - um_mmu.h was made into a userspace-usable file.
      
      - proc_mm and ptrace_faultinfo are globals which say whether the host
        supports these features.
      
      - There is a bad interaction between the mm.nr_ptes check at the end of
        exit_mmap, stack randomization, and skas0.  exit_mmap will stop freeing
        pages at the PGDIR_SIZE boundary after the last vma.  If the stack isn't
        on the last page table page, the last pte page won't be freed, as it
        should be since the stub ptes are there, and exit_mmap will BUG because
        there is an unfreed page.  To get around this, TASK_SIZE is set to the
        next lowest PGDIR_SIZE boundary and mm->nr_ptes is decremented after the
        calls to init_stub_pte.  This ensures that we know the process stack (and
        all other process mappings) will be below the top page table page, and
        thus we know that mm->nr_ptes will be one too many, and can be
        decremented.
      
      Things that need fixing:
      
      - We may need better assurrences that the stub code is PIC.
      
      - The stub pte is set up in init_new_context_skas.
      
      - alloc_pgdir is probably the right place.
      Signed-off-by: NJeff Dike <jdike@addtoit.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d67b569f
  29. 01 5月, 2005 1 次提交
  30. 17 4月, 2005 1 次提交
    • L
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds 提交于
      Initial git repository build. I'm not bothering with the full history,
      even though we have it. We can create a separate "historical" git
      archive of that later if we want to, and in the meantime it's about
      3.2GB when imported into git - space that would just make the early
      git days unnecessarily complicated, when we don't have a lot of good
      infrastructure for it.
      
      Let it rip!
      1da177e4