From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: Re: Issue with /proc/sys/net/ipv4/tcp_mem Date: Mon, 12 Oct 2015 11:37:02 -0500 Message-ID: <87io6coxg1.fsf@x220.int.ebiederm.org> References: <561B7F98.1040809@huawei.com> Mime-Version: 1.0 Content-Type: text/plain Cc: To: wangyufen Return-path: Received: from out03.mta.xmission.com ([166.70.13.233]:40167 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750890AbbJLQol (ORCPT ); Mon, 12 Oct 2015 12:44:41 -0400 In-Reply-To: <561B7F98.1040809@huawei.com> (wangyufen@huawei.com's message of "Mon, 12 Oct 2015 17:38:32 +0800") Sender: netdev-owner@vger.kernel.org List-ID: wangyufen writes: > Hi, > > I tried on linux-4.1: > linux:~# cat /proc/sys/net/ipv4/tcp_mem > 8388608 12582912 16777216 > linux:~# echo 1234 >/proc/sys/net/ipv4/tcp_mem > -bash: echo: write error: Invalid argument > linux:~# cat /proc/sys/net/ipv4/tcp_mem > 1234 12582912 16777216 > > the echo operation got error, but value already written to tcp_mem. > > I checked, patch f594d63199688ad568fb caused the issue. If your problem is that you can not write a single value and instead have to write all three values I don't know what to tell you. I don't see how that could have ever worked. Certainly the commit you pointed at did not change that behavior. Eric