[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: New dumping problem...

From: Jan D.
Subject: Re: New dumping problem...
Date: Tue, 29 Mar 2005 21:41:59 +0200
User-agent: Mozilla Thunderbird 1.0 (X11/20041206)

David Kastrup wrote:

On the newest Fedora Core tests, the setarch i386 workaround is no
longer sufficient for dumping.

It turns out that one way to fix this is to use

 echo 0 >/proc/sys/kernel/randomize_va_space

(which only root can do).

Uh oh.

Hmm, there is not much documentation of this, but what I can find is that this is a general feature in the Linux kernel from 2.6.11 or 2.6.12-rc1, so other GNU/Linux distributions may also have it. Apparently it also breaks dosemu.

The error message is

Dumping under names emacs and emacs-22.0.50
Warning: Your system has a gap between BSS and the
heap (6716260 byte).  This usually means that exec-shield
or something similar is in effect.  The dump may
fail because of this. See the section about exec-shield in etc/PROBLEMS for more information.
make[1]: *** [bootstrap-emacs] Segmentation fault
make[1]: Leaving directory `/usr/local/tmp/emacs-build/src'
make: *** [bootstrap-build] Error 2

It seems like we are playing catchup with the operating system's
security games.

Indeed. The final solution must be to either fix unexec (ELF I presume) or move away from unexec to something else. I think the only thing we can do for now is to note this in etc/PROBLEMS. It is too bad that root access is required on those systems to build Emacs.

   Jan D.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]