From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f52.google.com (mail-wm0-f52.google.com [74.125.82.52]) by kanga.kvack.org (Postfix) with ESMTP id 121116B0005 for ; Sat, 5 Mar 2016 03:10:05 -0500 (EST) Received: by mail-wm0-f52.google.com with SMTP id p65so47090875wmp.1 for ; Sat, 05 Mar 2016 00:10:05 -0800 (PST) Received: from mx5-phx2.redhat.com (mx5-phx2.redhat.com. [209.132.183.37]) by mx.google.com with ESMTPS id le8si7907881wjb.80.2016.03.05.00.10.02 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 05 Mar 2016 00:10:03 -0800 (PST) Date: Sat, 5 Mar 2016 03:09:50 -0500 (EST) From: Jan Stancek Message-ID: <983257005.5372143.1457165390827.JavaMail.zimbra@redhat.com> In-Reply-To: <20160304133807.72ede1000b9bf0b846d2fb87@linux-foundation.org> References: <20160304133807.72ede1000b9bf0b846d2fb87@linux-foundation.org> Subject: Re: [PATCH] mm/hugetlb: use EOPNOTSUPP in hugetlb sysctl handlers MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, n-horiguchi@ah.jp.nec.com, mike kravetz , hillf zj , kirill shutemov , dave hansen , paul gortmaker ----- Original Message ----- > From: "Andrew Morton" > To: "Jan Stancek" > Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, n-horiguchi@ah.jp.nec.com, "mike kravetz" > , "hillf zj" , "kirill shutemov" > , "dave hansen" , "paul gortmaker" > > Sent: Friday, 4 March, 2016 10:38:07 PM > Subject: Re: [PATCH] mm/hugetlb: use EOPNOTSUPP in hugetlb sysctl handlers > > On Thu, 3 Mar 2016 11:02:51 +0100 Jan Stancek wrote: > > > Replace ENOTSUPP with EOPNOTSUPP. If hugepages are not supported, > > this value is propagated to userspace. EOPNOTSUPP is part of uapi > > and is widely supported by libc libraries. > > hm, what is the actual user-visible effect of this change? Does it fix > some misbehaviour? > It gives nicer message to user, rather than: # cat /proc/sys/vm/nr_hugepages cat: /proc/sys/vm/nr_hugepages: Unknown error 524 And also LTP's proc01 test was failing because this ret code (524) was unexpected: proc01 1 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_hugepages: errno=???(524): Unknown error 524 proc01 2 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_hugepages_mempolicy: errno=???(524): Unknown error 524 proc01 3 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_overcommit_hugepages: errno=???(524): Unknown error 524 Regards, Jan -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org