[SCM] systemtap: system-wide probe/trace tool branch, master, updated. release-1.3-263-g33d60a8

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- Log -----------------------------------------------------------------
commit 33d60a821c49313350cf6e575697600004567f6f
Author: Josh Stone <jistone@redhat.com>
Date:   Wed Nov 3 10:34:39 2010 -0700

    uprobes: Fix post_ssout handling of "rep ret" on x86
    
    That odd sequence is apparently used to coerce better behavior from the
    branch predictor on AMD K8.  GCC does this, so we need to be prepared to
    deal with it.
    
    In uprobe_post_ssout, most instructions just need a relative %ip fixup
    after single-stepping out-of-line.  A few are special though, either
    because their new %ip is not relative, or because their return address
    on the stack needs that relative SSOL adjustment, or even both.  This
    oddball "rep ret" is such a case, but we were missing the proper fixup
    due to the unexpected prefix.
    
    This patch moves that ip-fixup decoding to the validation phase in
    setup_uprobe_post_ssout, saving the flags UPFIX_RETURN and UPFIX_ABS_IP
    as needed.  In this same step, we reject probing these instructions if
    they have a prefix, as we haven't determined the correct behavior for
    them.  For "rep ret" we make an explicit exception, since we know that
    behaves just like a bare "ret".

-----------------------------------------------------------------------

Summary of changes:
 runtime/uprobes/uprobes_i386.c   |  111 ++++++++++++++++++++-----------
 runtime/uprobes/uprobes_i386.h   |    7 ++-
 runtime/uprobes/uprobes_x86.c    |  133 ++++++++++++++++++++++----------------
 runtime/uprobes/uprobes_x86.h    |    7 ++-
 runtime/uprobes/uprobes_x86_64.c |  125 ++++++++++++++++++++++--------------
 runtime/uprobes/uprobes_x86_64.h |    2 +
 runtime/uprobes2/uprobes_x86.c   |  133 ++++++++++++++++++++++----------------
 runtime/uprobes2/uprobes_x86.h   |    7 ++-
 8 files changed, 324 insertions(+), 201 deletions(-)


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