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From: John Baldwin <jhb@freebsd.org>
To: freebsd-hackers@freebsd.org
Subject: Re: core dump vs kern.ipc.shm_use_phys
Date: Tue, 11 Feb 2014 13:21:02 -0500
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Cc: Andriy Gapon <avg@freebsd.org>, freebsd-arch@freebsd.org
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On Wednesday, January 22, 2014 6:32:01 am Andriy Gapon wrote:
> 
> I seems that if kern.ipc.shm_use_phys is enabled then shared memory regions are
> not included into a coredump.  Seems that each_writable_segment() in
> sys/kern/imgact_elf.c skips OBJT_PHYS objects.

Hmm, that may be a feature.  I often map large shared memory segments with
MAP_NOCORE on purpose.  Is it to tell if a given OBJT_PHYS object is a SYSV
SHM object?  (I assume it isn't.)

-- 
John Baldwin