1. 13 10月, 2007 3 次提交
  2. 07 8月, 2007 1 次提交
  3. 25 7月, 2007 1 次提交
  4. 21 7月, 2007 1 次提交
  5. 16 7月, 2007 5 次提交
  6. 03 5月, 2007 2 次提交
    • A
      KVM: Allow passing 64-bit values to the emulated read/write API · 4c690a1e
      Avi Kivity 提交于
      This simplifies the API somewhat (by eliminating the special-case
      cmpxchg8b on i386).
      Signed-off-by: NAvi Kivity <avi@qumranet.com>
      4c690a1e
    • A
      KVM: x86 emulator: fix bit string operations operand size · df513e2c
      Avi Kivity 提交于
      On x86, bit operations operate on a string of bits that can reside in
      multiple words.  For example, 'btsl %eax, (blah)' will touch the word
      at blah+4 if %eax is between 32 and 63.
      
      The x86 emulator compensates for that by advancing the operand address
      by (bit offset / BITS_PER_LONG) and truncating the bit offset to the
      range (0..BITS_PER_LONG-1).  This has a side effect of forcing the operand
      size to 8 bytes on 64-bit hosts.
      
      Now, a 32-bit guest goes and fork()s a process.  It write protects a stack
      page at 0xbffff000 using the 'btr' instruction, at offset 0xffc in the page
      table, with bit offset 1 (for the write permission bit).
      
      The emulator now forces the operand size to 8 bytes as previously described,
      and an innocent page table update turns into a cross-page-boundary write,
      which is assumed by the mmu code not to be a page table, so it doesn't
      actually clear the corresponding shadow page table entry.  The guest and
      host permissions are out of sync and guest memory is corrupted soon
      afterwards, leading to guest failure.
      
      Fix by not using BITS_PER_LONG as the word size; instead use the actual
      operand size, so we get a 32-bit write in that case.
      
      Note we still have to teach the mmu to handle cross-page-boundary writes
      to guest page table; but for now this allows Damn Small Linux 0.4 (2.4.20)
      to boot.
      Signed-off-by: NAvi Kivity <avi@qumranet.com>
      df513e2c
  7. 23 1月, 2007 1 次提交
    • A
      [PATCH] KVM: x86 emulator: fix bit string instructions · 038e51de
      Avi Kivity 提交于
      The various bit string instructions (bts, btc, etc.) fail to adjust the
      address correctly if the bit address is beyond BITS_PER_LONG.
      
      This bug creeped in as the emulator originally relied on cr2 to contain the
      memory address; however we now decode it from the mod r/m bits, and must
      adjust the offset to account for large bit indices.
      
      The patch is rather large because it switches src and dst decoding around, so
      that the bit index is available when decoding the memory address.
      
      This fixes workloads like the FC5 installer.
      Signed-off-by: NAvi Kivity <avi@qumranet.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      038e51de
  8. 06 1月, 2007 1 次提交
  9. 14 12月, 2006 1 次提交
  10. 11 12月, 2006 1 次提交
    • A
      [PATCH] kvm: userspace interface · 6aa8b732
      Avi Kivity 提交于
      web site: http://kvm.sourceforge.net
      
      mailing list: kvm-devel@lists.sourceforge.net
        (http://lists.sourceforge.net/lists/listinfo/kvm-devel)
      
      The following patchset adds a driver for Intel's hardware virtualization
      extensions to the x86 architecture.  The driver adds a character device
      (/dev/kvm) that exposes the virtualization capabilities to userspace.  Using
      this driver, a process can run a virtual machine (a "guest") in a fully
      virtualized PC containing its own virtual hard disks, network adapters, and
      display.
      
      Using this driver, one can start multiple virtual machines on a host.
      
      Each virtual machine is a process on the host; a virtual cpu is a thread in
      that process.  kill(1), nice(1), top(1) work as expected.  In effect, the
      driver adds a third execution mode to the existing two: we now have kernel
      mode, user mode, and guest mode.  Guest mode has its own address space mapping
      guest physical memory (which is accessible to user mode by mmap()ing
      /dev/kvm).  Guest mode has no access to any I/O devices; any such access is
      intercepted and directed to user mode for emulation.
      
      The driver supports i386 and x86_64 hosts and guests.  All combinations are
      allowed except x86_64 guest on i386 host.  For i386 guests and hosts, both pae
      and non-pae paging modes are supported.
      
      SMP hosts and UP guests are supported.  At the moment only Intel
      hardware is supported, but AMD virtualization support is being worked on.
      
      Performance currently is non-stellar due to the naive implementation of the
      mmu virtualization, which throws away most of the shadow page table entries
      every context switch.  We plan to address this in two ways:
      
      - cache shadow page tables across tlb flushes
      - wait until AMD and Intel release processors with nested page tables
      
      Currently a virtual desktop is responsive but consumes a lot of CPU.  Under
      Windows I tried playing pinball and watching a few flash movies; with a recent
      CPU one can hardly feel the virtualization.  Linux/X is slower, probably due
      to X being in a separate process.
      
      In addition to the driver, you need a slightly modified qemu to provide I/O
      device emulation and the BIOS.
      
      Caveats (akpm: might no longer be true):
      
      - The Windows install currently bluescreens due to a problem with the
        virtual APIC.  We are working on a fix.  A temporary workaround is to
        use an existing image or install through qemu
      - Windows 64-bit does not work.  That's also true for qemu, so it's
        probably a problem with the device model.
      
      [bero@arklinux.org: build fix]
      [simon.kagstrom@bth.se: build fix, other fixes]
      [uril@qumranet.com: KVM: Expose interrupt bitmap]
      [akpm@osdl.org: i386 build fix]
      [mingo@elte.hu: i386 fixes]
      [rdreier@cisco.com: add log levels to all printks]
      [randy.dunlap@oracle.com: Fix sparse NULL and C99 struct init warnings]
      [anthony@codemonkey.ws: KVM: AMD SVM: 32-bit host support]
      Signed-off-by: NYaniv Kamay <yaniv@qumranet.com>
      Signed-off-by: NAvi Kivity <avi@qumranet.com>
      Cc: Simon Kagstrom <simon.kagstrom@bth.se>
      Cc: Bernhard Rosenkraenzer <bero@arklinux.org>
      Signed-off-by: NUri Lublin <uril@qumranet.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Roland Dreier <rolandd@cisco.com>
      Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
      Signed-off-by: NAnthony Liguori <anthony@codemonkey.ws>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      6aa8b732