RE: [PATCH 9/9] gdb, mi: Add -shadow-stack-list-frames command

["Schimpe, Christina" <christina.schimpe@intel.com>]

Hi Eli,

Thank you for the review.

> -----Original Message-----
> From: Eli Zaretskii <eliz@gnu.org>
> Sent: Tuesday, September 23, 2025 1:54 PM
> To: Schimpe, Christina <christina.schimpe@intel.com>
> Cc: gdb-patches@sourceware.org
> Subject: Re: [PATCH 9/9] gdb, mi: Add -shadow-stack-list-frames command
> 
> > From: Christina Schimpe <christina.schimpe@intel.com>
> > Date: Tue, 23 Sep 2025 11:18:42 +0000
> >
> > Add the mi command for the subcommand "backtrace shadow".
> > Similar to the mi interface for the ordinary backtrace command,
> > support low-frame and high-frame as command line parameters.
> >
> > Example print of a full shadow stack backtrace:
> > ~~~
> > (gdb)
> > -shadow-stack-list-frames
> > ^done,shadow-stack=[
> > shadow-stack-frame={level="0",addr="0x00007ffff7c3fe70",
> >   func="__libc_start_call_main",file="../sysdeps/nptl/libc_start_call_main.h",
> >   fullname="/usr/[...]/sysdeps/nptl/libc_start_call_main.h",
> >   line="58",arch="i386:x86-64"},
> > shadow-stack-frame={level="1",addr="0x00007ffff7c3ff20",
> >   func="__libc_start_main_impl",file="../csu/libc-start.c",
> >   fullname="/usr/[...]/csu/libc-start.c",
> >   line="128",arch="i386:x86-64"},
> > shadow-stack-frame={level="2",addr="0x0000000000401075",
> >   func="_start",arch="i386:x86-64"}]
> > ~~~
> >
> > Example print of a shadow stack backtrace using low- and high-frame:
> > ~~~
> > (gdb)
> > -shadow-stack-list-frames 0 1
> > ^done,shadow-stack=[
> > shadow-stack-frame={level="0",addr="0x00007ffff7c3fe70",
> >   func="__libc_start_call_main",file="../sysdeps/nptl/libc_start_call_main.h",
> >   fullname="/usr/[...]/sysdeps/nptl/libc_start_call_main.h",
> >   line="58",arch="i386:x86-64"},
> > shadow-stack-frame={level="1",addr="0x00007ffff7c3ff20",
> >   func="__libc_start_main_impl",file="../csu/libc-start.c",
> >   fullname="/usr/[...]/csu/libc-start.c",
> >   line="128",arch="i386:x86-64"}]
> > ~~~
> > ---
> >  gdb/NEWS                                      |  10 ++
> >  gdb/doc/gdb.texinfo                           |  47 ++++++
> >  gdb/mi/mi-cmd-stack.c                         | 146 ++++++++++++++++++
> >  gdb/mi/mi-cmds.c                              |   2 +
> >  gdb/mi/mi-cmds.h                              |   1 +
> >  gdb/shadow-stack.c                            |  17 +-
> >  gdb/shadow-stack.h                            |  11 ++
> >  .../gdb.mi/mi-shadow-stack-signal.exp         |  69 +++++++++
> >  gdb/testsuite/gdb.mi/mi-shadow-stack.exp      |  65 ++++++++
> >  9 files changed, 365 insertions(+), 3 deletions(-)  create mode
> > 100644 gdb/testsuite/gdb.mi/mi-shadow-stack-signal.exp
> >  create mode 100644 gdb/testsuite/gdb.mi/mi-shadow-stack.exp
> 
> Thanks.
> 
> > diff --git a/gdb/NEWS b/gdb/NEWS
> > index eb96ff2ae08..3c52f88b71d 100644
> > --- a/gdb/NEWS
> > +++ b/gdb/NEWS
> > @@ -40,6 +40,16 @@ bt shadow [option]... [count | -count]
> >    Print backtrace of all shadow stack frames, or innermost 'count' frames.
> >    The command is a subcommand of the ordinary backtrace command.
> >
> > +* New MI commands
> > +
> > +-shadow-stack-list-frames
> > +
> > +  Added new MI command '-shadow-stack-list-frames' which is
> > + equivalent to  the CLI subcommand 'backtrace shadow' but supports
> > + 'low-frame' and  'high-frame' as command line parameters.  The
> > + parameters are used to  print shadow stack frames between certain
> > + levels on the shadow stack  only.
> 
> So we will support in MI features that are not supported by the CLI?
> Is that limitation really necessary?

The same limitations applies to the mi equivalent of the ordinary backtrace command,
(-stack-list-frames ) so I thought implementing it similar would make sense.

Christina
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