From owner-freebsd-net@freebsd.org Wed Jan 18 22:01:35 2017 Return-Path: Delivered-To: freebsd-net@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 38072CB6027 for ; Wed, 18 Jan 2017 22:01:35 +0000 (UTC) (envelope-from 01000159b390c409-5adcb488-67e8-4038-b9b0-5d4f33460205-000000@amazonses.com) Received: from a8-13.smtp-out.amazonses.com (a8-13.smtp-out.amazonses.com [54.240.8.13]) (using TLSv1 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id F1FE11441 for ; Wed, 18 Jan 2017 22:01:33 +0000 (UTC) (envelope-from 01000159b390c409-5adcb488-67e8-4038-b9b0-5d4f33460205-000000@amazonses.com) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=vnqrkfnvu6csdl6mwgk5t6ix3nnepx57; d=tarsnap.com; t=1484776326; h=Subject:To:References:Cc:From:Message-ID:Date:MIME-Version:In-Reply-To:Content-Type:Content-Transfer-Encoding; bh=vtJqVKg3jNMpvgvPT/3oZ82ggVQtkN5NgWFVkj2GAQA=; b=P8if18ktKI7XHRXiw+yX5FGQfxw/uclVsYvdRobDBg0tJKr3giYL7kZjohGPfKl1 PTOirY9X2fsUs6xdch+XAws9x2CaWaJnGLPMWER5HKF7vb5HzVfy95rg6W3K5upasv7 oOBwf3oNDnfk2Kty0GjkY8VX6BGk6yJ9eJ0AUKPQ= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=6gbrjpgwjskckoa6a5zn6fwqkn67xbtw; d=amazonses.com; t=1484776326; h=Subject:To:References:Cc:From:Message-ID:Date:MIME-Version:In-Reply-To:Content-Type:Content-Transfer-Encoding:Feedback-ID; bh=vtJqVKg3jNMpvgvPT/3oZ82ggVQtkN5NgWFVkj2GAQA=; b=NK1bYmEmJoXp+CUWi5AkUg/HSC/N78xqfNLWxV+9tsfaSEOv1rVo0G+bnJuqmZq/ mUSUto2c5j7Vuydy3IUYHGgzzVWnaspbJLqxcjaFcAapEN8oK/RgpoIkHl+ArDGY8sS E2iULdPyq8zoEsSpAK341FiKStnnn8iZ1DTIpWIE= Subject: Re: sosend returning ERESTART To: Konstantin Belousov References: <01000159aac969e6-b2fc3913-d04e-42d4-befd-402ed0d830bf-000000@email.amazonses.com> <20170117100634.GS2349@kib.kiev.ua> <01000159afddb7ce-064a5d17-4b81-4b2c-a9b4-3ddd2ad2e377-000000@email.amazonses.com> <20170118103650.GE2349@kib.kiev.ua> Cc: freebsd-net@freebsd.org From: Colin Percival Message-ID: <01000159b390c409-5adcb488-67e8-4038-b9b0-5d4f33460205-000000@email.amazonses.com> Date: Wed, 18 Jan 2017 21:52:06 +0000 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <20170118103650.GE2349@kib.kiev.ua> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-SES-Outgoing: 2017.01.18-54.240.8.13 Feedback-ID: 1.us-east-1.Lv9FVjaNvvR5llaqfLoOVbo2VxOELl7cjN0AOyXnPlk=:AmazonSES X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 Jan 2017 22:01:35 -0000 On 01/18/17 02:36, Konstantin Belousov wrote: > On Wed, Jan 18, 2017 at 04:37:40AM +0000, Colin Percival wrote: >> Thanks, looks like that was exactly it -- if the TCP send buffer was full >> we would call sbwait, and if a signal arrived it would return ERESTART. >> It looks like setting the SB_NOINTR flag will prevent this; I'm testing a >> patch right now. > > Note that passing SB_NOINTR unconditionally or even only for mounts > with nointr (default) option is wrong. You make the socket operation > uninterruptible, process terminate-ability becomes depended on the > external factor, the behaviour of the remote system. I'm not sure what you're getting at here. The fact that "NFS mounted without the intr flag" + "unresponsive NFS server" = "unkillable processes" has been a (mis)feature of NFS for decades. -- Colin Percival Security Officer Emeritus, FreeBSD | The power to serve Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid