From owner-freebsd-scsi@FreeBSD.ORG Thu Nov 8 10:25:15 2007 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 C70DF16A419 for ; Thu, 8 Nov 2007 10:25:15 +0000 (UTC) (envelope-from ivoras@gmail.com) Received: from rv-out-0910.google.com (rv-out-0910.google.com [209.85.198.188]) by mx1.freebsd.org (Postfix) with ESMTP id 8FAEC13C4C6 for ; Thu, 8 Nov 2007 10:25:15 +0000 (UTC) (envelope-from ivoras@gmail.com) Received: by rv-out-0910.google.com with SMTP id l15so92289rvb for ; Thu, 08 Nov 2007 02:25:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; bh=pswP2aIyCyKE5wANC8Oo8EvsQAwEWoGr53pGekKo4LE=; b=BrMfu/5ofWcYppJtwaUieHGCu3SrAdBA+NqvtdoO1Q9Kr0MRIVHd6E7LLlbQRjs9QsyIrOoC9VD+l2jVrOHAR379wC106IzwhNhvliZzFyBdwDi/4XLh/2e1STTTAlcT9D5Rtlz64k8Q3oBAf2+2yFyT72KLdghxJ2V6xQHmTGQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=UC/LskU1zfnJABri+HiIu3E2Q+UIRmgG0/9QCLRpYOrDpHRnA/5qV9qtWzzznKg04+K1jM7EQepbsvnVHau1tlUd4kGIjIQU97mFf1gxrTYj2uF9Uz9tOb73UhrkhQSjMD1DYsgJFdeDoUsfRUXB+UExj2zlWvZBB+Jyvyw+qFQ= Received: by 10.140.249.20 with SMTP id w20mr149091rvh.1194515783342; Thu, 08 Nov 2007 01:56:23 -0800 (PST) Received: by 10.141.211.5 with HTTP; Thu, 8 Nov 2007 01:56:23 -0800 (PST) Message-ID: <9bbcef730711080156n6a914be6m6ae478ceef7c14a9@mail.gmail.com> Date: Thu, 8 Nov 2007 10:56:23 +0100 From: "Ivan Voras" Sender: ivoras@gmail.com To: "Scott Long" In-Reply-To: <4732C7DC.60902@samsco.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <47300ADE.5070506@mansionfamily.plus.com> <4730C8EC.7050002@mansionfamily.plus.com> <4732C7DC.60902@samsco.org> X-Google-Sender-Auth: a2ad32b9d877a929 Cc: freebsd-scsi@freebsd.org Subject: Re: iSCSI in 7.0 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: Thu, 08 Nov 2007 10:25:15 -0000 On 08/11/2007, Scott Long wrote: > Unfortunately, the GEOM block layer is > not free of this deadlock, so this whole discussion is mostly academic > (the GEOM problem is small and very hard to trigger since it uses the > zone allocator, but problems have been observed in real-world > situations, which is a shame). Maybe not the GEOM layer itself but various GEOM classes. For example, most non-trivial classes spawn handler threads that do malloc(M_WAITOK).