x86, mpx updates for 4.1 (take 2)

Hi x86 maintainers,

It appeared that my attempt to send this earlier this week failed to reach at least some of the intended recipients. I updated a few of the patch descriptions and am resending.

There are 4 basic things going on here:
1. Make FPU/xsave code preempt safe and work properly
2. Add trace points to make kernel and app debugging easier
3. Add a boot-time disable for mpx
4. Support 32-bit binaries to run on 64-bit kernels

I've hesitated sending this in the past few weeks as the FPU code had a lot of churn and affected our ability to test on current kernels. It seems to have settled down and appears more stable now.

These are available against 4.0-rc4 in git as well:

git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx.git mpx-v17

Dave Hansen (17):
x86, fpu: wrap get_xsave_addr() to make it safer x86, mpx: use new tsk_get_xsave_addr() x86, mpx: trace #BR exceptions
x86, mpx: trace entry to bounds exception paths x86, mpx: trace when MPX is zapping pages x86, mpx: trace attempts to find bounds tables x86, mpx: trace allocation of new bounds tables x86, mpx: boot-time disable
x86: make is_64bit_mm() widely available
x86: make __VIRTUAL_MASK safe to use on 32 bit x86, mpx: we do not allocate the bounds directory x86, mpx: remove redundant MPX_BNDCFG_ADDR_MASK x86, mpx: Add temporary variable to reduce masking x86, mpx: new directory entry to addr helper x86, mpx: do 32-bit-only cmpxchg for 32-bit apps x86, mpx: support 32-bit binaries on 64-bit kernel x86, mpx: allow mixed binaries again

 Documentation/kernel-parameters.txt |   4 +
 arch/x86/include/asm/mmu_context.h  |  13 ++
 arch/x86/include/asm/mpx.h          |  74 +++++-----
 arch/x86/include/asm/page_types.h   |   8 ++
 arch/x86/include/asm/trace/mpx.h    | 133 ++++++++++++++++++
 arch/x86/include/asm/xsave.h        |   1 +
 arch/x86/kernel/cpu/common.c        |  16 +++
 arch/x86/kernel/traps.c             |  12 +-
 arch/x86/kernel/uprobes.c           |  10 +-
 arch/x86/kernel/xsave.c             |  32 +++++
 arch/x86/mm/mpx.c                   | 270 +++++++++++++++++++++++++++++-------
 11 files changed, 469 insertions(+), 104 deletions(-)
 create mode 100644 arch/x86/include/asm/trace/mpx.h

1.9.1