From owner-svn-src-head@freebsd.org Fri Oct 28 21:47:32 2016 Return-Path: Delivered-To: svn-src-head@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 D4EF1C25490; Fri, 28 Oct 2016 21:47:32 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from mail.baldwin.cx (bigwig.baldwin.cx [96.47.65.170]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id A73F51D37; Fri, 28 Oct 2016 21:47:32 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from ralph.baldwin.cx (c-73-231-226-104.hsd1.ca.comcast.net [73.231.226.104]) by mail.baldwin.cx (Postfix) with ESMTPSA id 54A1C10AF88; Fri, 28 Oct 2016 17:47:25 -0400 (EDT) From: John Baldwin To: Konstantin Belousov Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r307971 - head/sys/mips/include Date: Fri, 28 Oct 2016 14:46:48 -0700 Message-ID: <1929988.EGVZnnWLNP@ralph.baldwin.cx> User-Agent: KMail/4.14.10 (FreeBSD/11.0-PRERELEASE; KDE/4.14.10; amd64; ; ) In-Reply-To: <20161028175450.GE54029@kib.kiev.ua> References: <201610261737.u9QHb8Ps036831@repo.freebsd.org> <4639059.6gemL8B1hY@ralph.baldwin.cx> <20161028175450.GE54029@kib.kiev.ua> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.4.3 (mail.baldwin.cx); Fri, 28 Oct 2016 17:47:25 -0400 (EDT) X-Virus-Scanned: clamav-milter 0.99.2 at mail.baldwin.cx X-Virus-Status: Clean X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 28 Oct 2016 21:47:32 -0000 On Friday, October 28, 2016 08:54:50 PM Konstantin Belousov wrote: > On Fri, Oct 28, 2016 at 09:59:26AM -0700, John Baldwin wrote: > > Well, we could perhaps patch those to use SA_SIGINFO instead, but if it's > > a non-trivial amount of effort I'm not going to bother. I'm surprised that > > some of those would use sigcontext. Both mono and go post-date SA_SIGINFO > > being standardized and supported on FreeBSD AFAIK. Supporting sigcontext > > just means extra BSD-specific code in those applications compared to using > > SA_SIGINFO. :-/ > > For libunwind, I can see a rationale for struct sigcontext use. It seems > that on Linux, rt_sigreturn(2) syscall takes struct sigcontext *, and not > struct ucontext *, as the argument. This is not unreasonable, because > the additional ucontext fields make no sense for sigreturn, for us they > are copied into kernel AS but are also unused. > > So my FreeBSD port followed the existing Linux code. And I started wondering > should we change our sigreturn(2) to take sigcontext * instead of ucontext *. Hmm, that's an interesting thought (and it seems 'struct sigcontext' isn't BSD-only). We would definitely want to ensure that the initial bit of ucontext_t matches a sigcontext if we were to go that route. -- John Baldwin