[PATCH v2 0/3] vDSO reference parser updates and Go workaround

[Andy Lutomirski <luto@amacapital.net>]

Patches 1 and 2 update the vDSO reference parser.

Despite the late submission, this might be 3.16 material: it's just
documentation.  If I'd been more on top of this, I would have done it
for 3.15.  It's also probably worthwhile given that there is at least
one rather buggy vDSO parser in the wild.

Patch 3 makes "Hello world" as built by Go stop segfaulting.  It's
a performance regression for Go programs: it causes them to stop
finding any symbols in the vDSO, but that's a lot better than
segfaulting.

Changes from v1:
 - Improve portability of the vdso parser.
 - Add an explicit ELFCLASS check in the vdso parser (why not?).
 - Fix x32 build.
 - Add a comment describing what the hack works around, why, and where the
   Go bug was introduced.

Andy Lutomirski (3):
  doc,vdso: Make vDSO examples more portable
  x86,vdso: Add PUT_LE to store little-endian values
  x86,vdso: Hack to keep 64-bit Go programs working

 Documentation/vDSO/parse_vdso.c               | 67 ++++++++++++++++-----------
 Documentation/vDSO/vdso_standalone_test_x86.c | 45 ++++++++++++------
 Documentation/vDSO/vdso_test.c                | 52 +++++++++++++++++++++
 arch/x86/vdso/Makefile                        | 18 +++----
 arch/x86/vdso/vdso-fakesections.c             | 32 +++++++++++++
 arch/x86/vdso/vdso2c.c                        | 19 ++++++--
 arch/x86/vdso/vdso2c.h                        | 23 +++++++--
 7 files changed, 199 insertions(+), 57 deletions(-)
 create mode 100644 Documentation/vDSO/vdso_test.c
 create mode 100644 arch/x86/vdso/vdso-fakesections.c

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1.9.3