Re: Preparing for 0.155

[Mark Wielaard <mjw at redhat dot com>]

On Tue, Aug 21, 2012 at 01:44:34PM -0700, Roland McGrath wrote:
> I don't want to rush on any API/ABI additions.  Also note I will be out
> and incommunicado from this Friday through September 5th.  So if you
> want a release soon (which I think is a fine thing), we should just tie
> up the pure fixes and backend additions this week and let more additions
> wait for the next release.

That is fine. Anything we won't get in this week will get in the next
release in 2 months.
 
> > libelf: elf*_xlatetomd now works for cross-endian elf note data.
> 
> Upcase ELF.

Changed.
 
> >         elf_getshdr now works consistently on non-mmaped ELF files after
> >         calling elf_cntl(ELF_C_FDREAD).
> 
> This is just a bug fix and I don't think it needs to be described this way.

Suggestions for a better description welcome. Originally I had:
"elf_getshdr now doesn't sometimes assert on non-mmaped ELF files after
calling elf_cntl(ELF_C_FDREAD)."
 
> >        Support for DWZ multifile forms DW_FORM_GNU_ref_alt/strp_alt.
> 
> This is a problematic addition that opens new security issues in the
> tools.  Since DWZ is not yet in wide use, if we want to make a release
> soon perhaps we should disable some of this support.  It's also an
> extreme API layering violation.  Doing this in a responsible way needs
> much more thought, so I think the only right thing to do for an imminent
> release is to disable the libdw support entirely.

It will be fine. The alt files are only parsed when the user has control
over the to open file contents in the first place. But I will ask the GDB
hackers if they saw any issues. The alt_ref support isn't some last minute
feature that didn't see any design or testing. I did consult with Jakub
to make sure I understood all details of the spec and the dwz
implementation. I coordinated with Tom to make sure GDB and elfutils
interpreted them the same way. Tom was also nice enough to review the
initial patch. The initial patch was posted publicly 2 months ago. We
discussed in in person at the Cauldron. Based on that I posted a version
that didn't have any api changes one month ago so everything is just
implementation details we can still change. It was tested in fedora
rawhide during the rebuild that created dwz files for all debuginfo
packages. And I made sure that stap works smoothly with it. Only after
all that it was committed begin of this month. It might be we missed
some issues, but that will just be bugs we will eventually find and fix
for a next release.

Cheers,

Mark