From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexei Starovoitov Subject: Re: [PATCH 1/2] bpf: do not use KMALLOC_SHIFT_MAX Date: Fri, 16 Dec 2016 15:23:42 -0800 Message-ID: <20161216232340.GA99159@ast-mbp.thefacebook.com> References: <20161215164722.21586-1-mhocko@kernel.org> <20161215164722.21586-2-mhocko@kernel.org> <20161216180209.GA77597@ast-mbp.thefacebook.com> <20161216220235.GD7645@dhcp22.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-mm@kvack.org, Cristopher Lameter , Andrew Morton , Alexei Starovoitov , netdev@vger.kernel.org, Daniel Borkmann To: Michal Hocko Return-path: Received: from mail-pg0-f67.google.com ([74.125.83.67]:33428 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758550AbcLPXXq (ORCPT ); Fri, 16 Dec 2016 18:23:46 -0500 Received: by mail-pg0-f67.google.com with SMTP id 3so11070205pgd.0 for ; Fri, 16 Dec 2016 15:23:46 -0800 (PST) Content-Disposition: inline In-Reply-To: <20161216220235.GD7645@dhcp22.suse.cz> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Dec 16, 2016 at 11:02:35PM +0100, Michal Hocko wrote: > On Fri 16-12-16 10:02:10, Alexei Starovoitov wrote: > > On Thu, Dec 15, 2016 at 05:47:21PM +0100, Michal Hocko wrote: > > > From: Michal Hocko > > > > > > 01b3f52157ff ("bpf: fix allocation warnings in bpf maps and integer > > > overflow") has added checks for the maximum allocateable size. It > > > (ab)used KMALLOC_SHIFT_MAX for that purpose. While this is not incorrect > > > it is not very clean because we already have KMALLOC_MAX_SIZE for this > > > very reason so let's change both checks to use KMALLOC_MAX_SIZE instead. > > > > > > Cc: Alexei Starovoitov > > > Signed-off-by: Michal Hocko > > > > Nack until the patches 1 and 2 are reversed. > > I do not insist on ordering. The thing is that it shouldn't matter all > that much. Or are you worried about bisectability? This patch 1 strongly depends on patch 2 ! Therefore order matters. The patch 1 by itself is broken. The commit log is saying '(ab)used KMALLOC_SHIFT_MAX for that purpose .. use KMALLOC_MAX_SIZE instead' that is also incorrect. We cannot do that until KMALLOC_MAX_SIZE is fixed. So please change the order and fix the commit log to say that KMALLOC_MAX_SIZE is actually valid limit now. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id 6509A6B0038 for ; Fri, 16 Dec 2016 18:23:47 -0500 (EST) Received: by mail-pf0-f197.google.com with SMTP id 144so143971845pfv.5 for ; Fri, 16 Dec 2016 15:23:47 -0800 (PST) Received: from mail-pg0-x242.google.com (mail-pg0-x242.google.com. [2607:f8b0:400e:c05::242]) by mx.google.com with ESMTPS id 19si9792411pfr.164.2016.12.16.15.23.46 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 16 Dec 2016 15:23:46 -0800 (PST) Received: by mail-pg0-x242.google.com with SMTP id p66so11056942pga.2 for ; Fri, 16 Dec 2016 15:23:46 -0800 (PST) Date: Fri, 16 Dec 2016 15:23:42 -0800 From: Alexei Starovoitov Subject: Re: [PATCH 1/2] bpf: do not use KMALLOC_SHIFT_MAX Message-ID: <20161216232340.GA99159@ast-mbp.thefacebook.com> References: <20161215164722.21586-1-mhocko@kernel.org> <20161215164722.21586-2-mhocko@kernel.org> <20161216180209.GA77597@ast-mbp.thefacebook.com> <20161216220235.GD7645@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161216220235.GD7645@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: linux-mm@kvack.org, Cristopher Lameter , Andrew Morton , Alexei Starovoitov , netdev@vger.kernel.org, Daniel Borkmann On Fri, Dec 16, 2016 at 11:02:35PM +0100, Michal Hocko wrote: > On Fri 16-12-16 10:02:10, Alexei Starovoitov wrote: > > On Thu, Dec 15, 2016 at 05:47:21PM +0100, Michal Hocko wrote: > > > From: Michal Hocko > > > > > > 01b3f52157ff ("bpf: fix allocation warnings in bpf maps and integer > > > overflow") has added checks for the maximum allocateable size. It > > > (ab)used KMALLOC_SHIFT_MAX for that purpose. While this is not incorrect > > > it is not very clean because we already have KMALLOC_MAX_SIZE for this > > > very reason so let's change both checks to use KMALLOC_MAX_SIZE instead. > > > > > > Cc: Alexei Starovoitov > > > Signed-off-by: Michal Hocko > > > > Nack until the patches 1 and 2 are reversed. > > I do not insist on ordering. The thing is that it shouldn't matter all > that much. Or are you worried about bisectability? This patch 1 strongly depends on patch 2 ! Therefore order matters. The patch 1 by itself is broken. The commit log is saying '(ab)used KMALLOC_SHIFT_MAX for that purpose .. use KMALLOC_MAX_SIZE instead' that is also incorrect. We cannot do that until KMALLOC_MAX_SIZE is fixed. So please change the order and fix the commit log to say that KMALLOC_MAX_SIZE is actually valid limit now. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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