From owner-freebsd-arm@freebsd.org  Tue Feb  7 18:47:06 2017
Return-Path: <owner-freebsd-arm@freebsd.org>
Delivered-To: freebsd-arm@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id D9409CD41D9
 for <freebsd-arm@mailman.ysv.freebsd.org>;
 Tue,  7 Feb 2017 18:47:06 +0000 (UTC)
 (envelope-from freebsd.contact@marino.st)
Received: from shepard.synsport.com (mail.synsport.com [208.69.230.148])
 (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id B4C6D1627
 for <freebsd-arm@freebsd.org>; Tue,  7 Feb 2017 18:47:06 +0000 (UTC)
 (envelope-from freebsd.contact@marino.st)
Received: from [127.0.0.1] (ip72-204-83-236.fv.ks.cox.net [72.204.83.236])
 (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits))
 (No client certificate requested)
 by shepard.synsport.com (Postfix) with ESMTP id 1EC1143CC8;
 Tue,  7 Feb 2017 12:45:22 -0600 (CST)
To: freebsd-arm@freebsd.org
Reply-To: marino@freebsd.org
From: John Marino <freebsd.contact@marino.st>
Subject: ARM64: PC/IP not saved in signal frame
Cc: Andreas Tobler <andreastt@gmail.com>
Message-ID: <530c18cd-d50d-4709-a0ca-22324a0cb592@marino.st>
Date: Tue, 7 Feb 2017 12:47:01 -0600
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101
 Thunderbird/45.1.1
MIME-Version: 1.0
X-Antivirus: avast! (VPS 170206-3, 02/06/2017), Outbound message
X-Antivirus-Status: Clean
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
X-Content-Filtered-By: Mailman/MimeDel 2.1.23
X-BeenThere: freebsd-arm@freebsd.org
X-Mailman-Version: 2.1.23
Precedence: list
List-Id: "Porting FreeBSD to ARM processors." <freebsd-arm.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-arm>,
 <mailto:freebsd-arm-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-arm/>
List-Post: <mailto:freebsd-arm@freebsd.org>
List-Help: <mailto:freebsd-arm-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-arm>,
 <mailto:freebsd-arm-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 07 Feb 2017 18:47:06 -0000

Hi guys,
I've been struggling to provide unwind support on the aarch64-*-freebsd* 
target of FreeBSD.  The only working example on this arch is 
aarch64-linux (attached).  I think I'm 99% done with the freebsd version 
(attached) but the last value that needs to be pass to the 
_Unwind_FrameState is the program counter offset.

I know the PC is not register-based on aarch64.  Linux still saves the 
value in the signal context, but AFAICT FreeBSD does not.

Can somebody
A) confirm that the program counter is missing from the saved signal context
B) confirm that it needs to be added for proper signal frame unwinding?

Alternatively, maybe somebody can figure out a solution given the 
current freebsd structures, but I'm losing hope on that one. (line 99)

Regards,
John