1. 25 Oct, 2016 40 commits
    • Charlie Jacobsen's avatar
    • Charles Jacobsen's avatar
      Wasn't doing a get/put on kthread. · 7ac8a242
      Charles Jacobsen authored
      Still haven't figured out page fault bug.
      7ac8a242
    • Charles Jacobsen's avatar
      Fixed build errors, module init tools. · 0f690a86
      Charles Jacobsen authored
      Getting nasty runtime bugs though.
      0f690a86
    • Charlie Jacobsen's avatar
      Finished the majority of the arch-indep code changes needed. · d71afeb4
      Charlie Jacobsen authored
      Refactored lcd's into lcd and lcd_thread. Still need to test/update
      tests.
      d71afeb4
    • Charles Jacobsen's avatar
      All (simple) lcd arch tests passing. · bee0375b
      Charles Jacobsen authored
      bee0375b
    • Charles Jacobsen's avatar
      3c809a98
    • Charlie Jacobsen's avatar
    • Charlie Jacobsen's avatar
      Separated lcd into container and thread objects. · dbc4e40c
      Charlie Jacobsen authored
      Updated code. Removed gdt/tss/idt for now. Added doc directory
      and some initial doc.
      dbc4e40c
    • Charles Jacobsen's avatar
    • Charles Jacobsen's avatar
      Switched to a kmem cache for allocating lcd_arch's. · 0f6ce597
      Charles Jacobsen authored
      Was getting bad load/store msr addresses for vm exits.
      Properly detected by the lcd_arch_check code.
      
      In struct lcd_arch, the msr_autoload fields were not
      word aligned in some instances (see requirement
      in Intel SDM V3 26.2.1.2). Even with compiler align
      attributes, if we use kmalloc, proper alignment is
      not guaranteed - we can allocate a struct lcd_arch
      on the wrong byte and it throws off the alignment
      of the entire struct.
      
      kmem cache allows specifying alignment. Appears to be
      working correctly.
      0f6ce597
    • Charlie Jacobsen's avatar
      Basic lcd module create, run, and destroy. · e0193fa4
      Charlie Jacobsen authored
      This code is ugly, but it's working.
      
      Tested with basic module, and appears to be working
      properly. I will soon incorporate the patched
      modprobe into the kernel tree, and then this code
      will be usable by everyone.
      
      The ipc code is still unimplemented. The only
      hypercall handled is yield. Also note that other
      exit conditions (e.g. external interrupt) have not
      been fully tested.
      
      Overview:
      -- kernel code calls lcd_create_as_module with
         the module's name
      -- lcd_create_as_module loads the module using
         request_lcd_module (request_lcd_module calls
         the patched modprobe to load the module, and
         the patched modprobe calls back into the lcd
         driver via the ioctrl interface to load the
         module)
      -- lcd_create_as_module then finds the loaded
         module, spawns a kernel thread and passes off
         the module to it
      -- the kernel thread initializes the lcd and
         maps the module inside it, then suspends itself
      -- lcd_run_as_module wakes up the kernel thread
         and tells it to run
      -- lcd_delete_as_module stops the kernel thread
         and deletes the module from the host kernel
      
      File-by-file details:
      
      arch/x86/include/asm/lcd-domains-arch.h
      arch/x86/lcd-domains/lcd-domains-arch-tests.c
      arch/x86/lcd-domains/lcd-domains-arch.c
      -- lcd was not running in 64-bit mode, and my
         checks had one subtle bug
      -- fixed %cr3 load to properly load vmcs first
      -- fixed set program counter to use guest virtual
         rather than guest physical address
      
      include/linux/sched.h
      -- added struct lcd to task_struct
      
      include/linux/init_task.h
      -- lcd pointer set to null when task_struct is
         initialized
      
      include/linux/module.h
      kernel/module.c
      -- made init_module and delete_module system calls
         callable from kernel code
      -- available in module.h via do_sys_init_module and
         do_sys_delete_module
      -- simply moved the majority of the guts of the
         system calls into a non-system call, exported
         routine
      -- take an extra flag, for_lcd; when set, the init
         code skips over running (and deallocating) the
         module's init code, and the delete code skips
         over running the module exit
      -- system calls from user code set for_lcd = 0; this
         ensures existing code still works
      
      include/linux/kmod.h
      kernel/kmod.c
      kernel/sysctl.c
      -- changed __request_module to __do_request_module; takes
         one extra argument, for_lcd
      -- __request_module   ==>  __do_request_module with for_lcd = 0
      -- request_lcd_module ==>  __do_request_module with for_lcd = 1
      -- call_modprobe conditionally uses lcd_modprobe_path, the path
         to a patched modprobe accessible via sysfs
      
      include/lcd-domains/lcd-domains.h
      -- added lcd status enum; see source code doc
      -- three routines for creating/running/destroying
         lcd's that use modules; see source code doc
      
      include/uapi/linux/lcd-domains.h
      -- added interface defns for patched modprobe to call into
         lcd driver for module init; lcd driver loads
         module (via slightly refactored module.c code) on behalf
         of modprobe
      
      virt/lcd-domains/lcd-domains.c
      -- implementation of routines for modules inside lcd's
      -- implementation of module init / delete for lcd's
         (uses patched module.c code)
      
      virt/lcd-domains/Kconfig
      virt/lcd-domains/Makefile
      virt/lcd-domains/lcd-module-load-test.c
      virt/lcd-domains/lcd-tests.c
      -- added test module for lcd module code
      -- test runs automatically when lcd module is inserted
      e0193fa4
    • Charles Jacobsen's avatar
      Simple blob successfully runs and returns in vmx. · c4fc774c
      Charles Jacobsen authored
      In the process of debugging, major corrections and
      debug checks implemented (this is a big squash):
      -- coded up entry checks documented in Intel SDM
         V3 chp 26 (this should help later if settings
         are changed, make it less risky to experiment
         and give more confidence)
      -- fixed host tr base addr bug (the worst bug! caused
         system to hang and then crash, since the tss
         was erroneous...)
      -- fixed vmx_entry to properly set host rsp before
         entry
      -- setting host sysenter and idt info
      -- fixed cs ar bytes bug
      -- fixed gdt limit bug
      -- fixed tr type bug
      -- extra settings added to cr0 and cr4, but may
         not be needed ... (debug fix attempt)
      -- lstar mstar autoload, may not be needed ...
         (debug fix attempt)
      c4fc774c
    • Charles Jacobsen's avatar
      Fixed build errors, all tests passing. · 78569fe2
      Charles Jacobsen authored
      Fixed (another) nasty casting bug in the
      code that initializes the ept pointer. I
      was using the old way of casting, and overlooking
      that I was storing a host virtual pointer
      inside a host physical pointer. This caused
      invept to fail (invept checks if the eptp is
      valid).
      
      I also fixed invept and invvpid to print an
      error message (like vmload and vmclear), rather
      than generate an invalid opcode exception. It's
      easier to debug and understand the problem.
      
      In the future, we could more carefully parse the
      error returned.
      78569fe2
    • Charles Jacobsen's avatar
      Minor build bug fixes. · f9875eab
      Charles Jacobsen authored
      (Sorry for the barrage of pushes, but I want
      to make sure I push changes in case I crash
      the machine...)
      f9875eab
    • Charles Jacobsen's avatar
      Most build errors fixed. · e6442a9d
      Charles Jacobsen authored
      e6442a9d
    • Charles Jacobsen's avatar
      89d31ccd
    • Charlie Jacobsen's avatar
      Introducing types for each gpa, gva, hva, hpa. · 82aa94ed
      Charlie Jacobsen authored
      Constructors and casting inlines are in arch-dep
      code header.
      82aa94ed
    • Charles Jacobsen's avatar
      e1504369
    • Charles Jacobsen's avatar
      b9f6d8fb
    • Charlie Jacobsen's avatar
      Shifted gpa map / unmap range to arch-dep code. · f9b52a46
      Charlie Jacobsen authored
      Updated tests.
      f9b52a46
    • Charles Jacobsen's avatar
      Fixing up ept destroy to not free mapped mem. · 8a977687
      Charles Jacobsen authored
      Originally, destroying the ept structures also
      freed the mapped host physical memory. This is
      leading to bad double free errors. Instead, I
      will report a potential memory leak if an ept
      pte is present.
      
      Users of the ept should unmap any host phys
      memory before destroying the ept (will shift
      over ept unmap range from arch-indep to
      arch-dep next).
      
      Updated arch test04 to use vmx_free_ept, now
      that it doesn't try to free mapped host phys
      mem.
      8a977687
    • Charlie Jacobsen's avatar
      Small fix to arch set pc. · 32c30a68
      Charlie Jacobsen authored
      Need to load vmcs in order to modify it.
      32c30a68
    • Charles Jacobsen's avatar
      Fixed bug in lcd_arch: vmx_init_stack. · dfb4c23b
      Charles Jacobsen authored
      Can't set stack pointer until vmcs is loaded.
      dfb4c23b
    • Charles Jacobsen's avatar
      Fixed build errors for first test. · 8a1846ba
      Charles Jacobsen authored
      Pushing in case of crash ...
      8a1846ba
    • Charles Jacobsen's avatar
      4e95f355
    • Charlie Jacobsen's avatar
      Most guest virtual paging code in place (untested). · fa756550
      Charlie Jacobsen authored
      This was tricky. Unfortunately, since guest physical
      addresses are wrapped in the paging entries, we can't
      use some of the linux macros / routines (e.g.,
      pud_offset). This would allow us to benefit from pud-
      and pmd-folding, making the code more portable. Perhaps
      we'll think of something later...
      
      The code will only work on a linux with 4 paging levels
      (pgd, pud, pmd, page table). lcd_mm_gva_walk is the
      main routine that traverses the hierarchy. Each subroutine
      translates a paging structures guest physical to host
      virtual address, and gets the correct entry.
      
      A simple watermark is used (rather than a bitmap) for
      allocating guest physical memory.
      fa756550
    • Charlie Jacobsen's avatar
      Simple explicit tss, gdt, and stack tear down. · fa05c7bf
      Charlie Jacobsen authored
      (Code before relied on free ept to free memory. But
      this could be confusing and hard to debug in the future...)
      fa05c7bf
    • Charlie Jacobsen's avatar
      Simple unmapping code for ept in arch-dep code. · a6130165
      Charlie Jacobsen authored
      Just clears the ept entry.
      a6130165
    • Charlie Jacobsen's avatar
      More work on blob initialization. · 33d999d6
      Charlie Jacobsen authored
      arch/x86/lcd-domains/...
      -- Fixed program counter and stack pointer initialization
      -- Added guest virtual paging pointer modifier routine
      
      include/lcd-domains/lcd-domains.h
      -- Added the minimum amount of data for guest virtual paging
         setup
      
      virt/lcd-domains/lcd-domains.c
      -- Added general routines for lcd create / destroy.
      -- Moved mm code to this file (to avoid future name clashes and
         be more self contained ... is this why kernel source files are
         so big?)
      -- Added general routine for initializing an lcd's gva.
      -- Re-factored blob initialization to use mm routines. Documented
         memory layout in the source code.
      
      Problem: I'm relying heavily on the ept tear down to free any
      memory mapped in there. But this is getting ugly ... Next step:
      Write quick routines to properly unmap and explicitly free memory.
      33d999d6
    • Charles Jacobsen's avatar
      7934847d
    • Charlie Jacobsen's avatar
      Driver code and interface for loading a blob in an lcd (untested). · f0735fd0
      Charlie Jacobsen authored
      User code calls ioctl with LCD_RUN_BLOB ioctl number and
      lcd_blob_info (containing userspace address of blob and
      blob order) -- defined in public include/linux/lcd-domains.h.
      
      The blob must be N pages, and N must be a power of 2 (for
      easy driver code). blob_order = log2(N). The blob consists
      of machine instructions that are loaded in the lcd and
      executed. The machine instructions cannot access any memory,
      including the stack (for now, until gv paging is in place).
      
      -- Added lcd_arch_set_pc for setting the lcd's program counter.
      -- Added driver code in lcd-domains.c for handling the ioctl
         request, loading the blob from user space into a fresh lcd,
         and running the lcd (in a loop).
      f0735fd0
    • Charles Jacobsen's avatar
      Fixed tss/stack remap bug, and double free in create. · e0ca0ea1
      Charles Jacobsen authored
      Some data structures in struct lcd_arch are mapped in
      the ept (so that the lcd has access to them). When the
      ept is freed, these data structures are freed.
      
      All tests passing now for lcd_arch_create.
      e0ca0ea1
    • Charles Jacobsen's avatar
      Fixed bad EPT bug (in free ept). No apparent bugs now. · 3360de4b
      Charles Jacobsen authored
      Switch from macros to inline functions for type safety
      and sanity.
      3360de4b
    • Charles Jacobsen's avatar
      Fixed EPT indexing bug. · c4af45ef
      Charles Jacobsen authored
      EPT stress test04 now passes (aside from free ept).
      c4af45ef
    • Charles Jacobsen's avatar
      Fixed some bugs in test04. · 131e8ca7
      Charles Jacobsen authored
      131e8ca7
    • Charlie Jacobsen's avatar
      More EPT stress testing. · 22d545d3
      Charlie Jacobsen authored
      22d545d3
    • Charles Jacobsen's avatar
    • Charlie Jacobsen's avatar
      Starting simple regression test code, to save debugging time. · a64b8301
      Charlie Jacobsen authored
      Successful build and insmod on emulab, but errors when trying
      to create lcd (perhaps errors mapping in ept). Regression tests
      should help and save debugging time in future.
      a64b8301
    • Charlie Jacobsen's avatar
      Simple renaming lcd => lcd-domains. · f34be85a
      Charlie Jacobsen authored
      Updated Kbuild, Kconfig, Makefiles.
      f34be85a
    • Charles Jacobsen's avatar
      a8810c51