From owner-freebsd-scsi@FreeBSD.ORG Fri Mar 12 19:11:40 2010 Return-Path: Delivered-To: freebsd-scsi@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 7E656106568A; Fri, 12 Mar 2010 19:11:40 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from fg-out-1718.google.com (fg-out-1718.google.com [72.14.220.152]) by mx1.freebsd.org (Postfix) with ESMTP id AABB08FC18; Fri, 12 Mar 2010 19:11:39 +0000 (UTC) Received: by fg-out-1718.google.com with SMTP id e21so459893fga.13 for ; Fri, 12 Mar 2010 11:11:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:message-id:date:from :user-agent:mime-version:to:cc:subject:references:in-reply-to :x-enigmail-version:content-type:content-transfer-encoding; bh=3ZZdbbVAwmDEQNgzfBUI4vJnQ46YY2bwViS9tT72wvU=; b=TRKVxvTI7juKQ3fhadwGQVtYpWMp4NwL4ZhWnWrSSFkrhJ6PoCJvkvFU/rjrrOA8zs ETxvsZCVyrMkmbmN4FfGJ9G0apoRZJCpcaG5bsw5a3rSJxfmt03h7CA3eCN6XVd5/MSi zqIrZyBh0HTPbQ4Z65nFCsVjVMkRBSYcAotPs= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=J5wHwARQ9PC53C2gCJqxWyrLOe1aktsxe2dKSmQs/YF0v/uS0ISaQCH2AOkDDHRxYT qp5XMRAbOvogEswQ63NggRrt6u1KmoLkg51jmn91XsJuXUUoSNhPy+TvY/lSjx7vbVw1 WpQ1yHQNud/B8FDnFbw8DF+sB+ryqo2ZV5iUM= Received: by 10.87.66.14 with SMTP id t14mr4211950fgk.60.1268421098371; Fri, 12 Mar 2010 11:11:38 -0800 (PST) Received: from mavbook.mavhome.dp.ua (s224.GtokyoFL6.vectant.ne.jp [222.228.90.224]) by mx.google.com with ESMTPS id 14sm1230553fxm.13.2010.03.12.11.11.35 (version=SSLv3 cipher=RC4-MD5); Fri, 12 Mar 2010 11:11:37 -0800 (PST) Sender: Alexander Motin Message-ID: <4B9A91DA.7030107@FreeBSD.org> Date: Fri, 12 Mar 2010 21:11:22 +0200 From: Alexander Motin User-Agent: Thunderbird 2.0.0.23 (X11/20091212) MIME-Version: 1.0 To: Attilio Rao References: <3bbf2fe11002281655i61a5f0a0if3f381ad0c4a1ef8@mail.gmail.com> <3bbf2fe11003031357o518d6028m8157d9110a9122f3@mail.gmail.com> <4B8EF128.8050704@feral.com> <3bbf2fe11003031532u2207eb55h19c3a045215a7d84@mail.gmail.com> <4B8EF336.80107@feral.com> <3bbf2fe11003031547kd5f7314t3d83b2bde06c1c2f@mail.gmail.com> <4B8EF990.5030407@feral.com> <3bbf2fe11003031607wa3727b5ke89bc2a909d4d6a6@mail.gmail.com> <4B901419.8060800@feral.com> <3bbf2fe11003041737p30690522ya81e1b8f4bd6bbf9@mail.gmail.com> <3bbf2fe11003120601y3c403a1ct50f9fc6c1f0903bf@mail.gmail.com> In-Reply-To: <3bbf2fe11003120601y3c403a1ct50f9fc6c1f0903bf@mail.gmail.com> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: freebsd-scsi@freebsd.org, "Justin T. Gibbs" , mj@feral.com Subject: Re: How is supposed to be protected the units list? X-BeenThere: freebsd-scsi@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SCSI subsystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Mar 2010 19:11:40 -0000 Attilio Rao wrote: > 2010/3/5 Attilio Rao : >> 2010/3/4 Matthew Jacob : >>> The referred to patch at least got me out of panic case :-).. >>> >>> http://people.freebsd.org/~mjacob/scsi_da.c.patch >> Yes, honestly the main intent of this patch is to offer a stable >> ground for correct handling of periph. When looking about refcounting >> them correctly, the main problem is that there was no initial >> condition assuring safety, and the initial patch should address this, >> but I'm sure there are places where periph refcount is not handled >> correctly and this may be one. > > So, as long as it seems nobody had a strong argument against this > patch, what do you think about me committing it? > We can further refine later if we think it is the case. > > Also, I think that Matt's patch should be committed just after this > one (and possibly we should investigate a similar add-on for the ata > counterpart too?). I have already told my opinion, that second lock may be not needed. I would like to think a bit more about both patches after getting back from the conference. Thanks, -- Alexander Motin