More mmap/Linux questions

More mmap/Linux questions

[j_clifton]

A previous thread on mmap stated that the problem is in Linux.

I have a cluster of Linux boxes connected via PCI reflective memory. They are
programmed in ADA and have 85 data structures mmaped into the reflective memory.
If I print or x any any structure which has been mmapped all I get are zeros. My
understanding is this is because of ptrace in the linux kernel.

The previous thread indicated this restriction was because some hardware devices
don't like arbitrary accesses. This restriction seems like swatting flies with a
sledgehammer. Can't MTTR or something be used to protect touchy hardware rather
than prohibiting all access to addresses above CPU memory?

Can someone familiar with the Linux Kernel (2.2 or higher) explain this in more
detail. Can I patch the kernel to get rid of this behaviour?

Re: More mmap/Linux questions

[Mark Kettenis]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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   Date: Thu, 31 Aug 2000 12:52:02 -0400
   From: <j_clifton@aerosimulation.com>

   Can someone familiar with the Linux Kernel (2.2 or higher) explain this in more
   detail. Can I patch the kernel to get rid of this behaviour?

You'll probably have more success asking your question on the
linux-kernel mailing list (linux-kernel@kernel.org).

Mark
From olivier.isnard@ipsn.fr Fri Sep 01 02:32:00 2000
From: ISNARD Olivier 132311 <olivier.isnard@ipsn.fr>
To: "'gdb@sources.redhat.com'" <gdb@sources.redhat.com>
Subject: Q: using gdb and lahey compiler
Date: Fri, 01 Sep 2000 02:32:00 -0000
Message-id: <FEC064C12976D31197DA00A0C9E93C90760ED3@ALGER>
X-SW-Source: 2000-09/msg00000.html
Content-length: 445

Hi all !

For some reason I have to use the Lahey fortran 90 compiler and I wonder if
it is possible to debug
such a generated program with gdb. I'm also using cygwin (NT pc).




____________

Dr. Olivier Isnard
IPSN
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