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From: "John S. Dyson" <toor@dyson.iquest.net>
Message-Id: <199610212156.QAA01345@dyson.iquest.net>
Subject: Re: kern/1848: breakpoints in shared libraries don't fire
To: bde@zeta.org.au (Bruce Evans)
Date: Mon, 21 Oct 1996 16:56:02 -0500 (EST)
Cc: jdp@polstra.com, msmith@atrad.adelaide.edu.au, freebsd-current@freebsd.org
In-Reply-To: <199610212135.HAA29513@godzilla.zeta.org.au> from "Bruce Evans" at Oct 22, 96 07:35:39 am
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> 
> >The text segment starts out read-only.  GDB does (or at least did)
> >change the protections to read/write as needed when it has to insert a
> >breakpoint.  As John-Mark Gurney pointed out in a different posting,
> >this all used to work just fine.  If it's broken now in -current, then
> >it's probably a problem with gdb.
> >
> >I just checked it on a current from just a few days ago, and it works
> >fine for me.  I was able to set a breakpoint on gethostbyname() in libc,
> 
> It's broken somewhere in vm now.  procfs_domem() returns 0 without
> writing anything, as if for EOF.  (procfs_rwmem() gets to the
> (writing && object->backing_object) case.  Then m == 0 and vm_fault()
> returns 0, but the faulted-in page is not used.)
> 
I'll fix!!!

John