From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754677AbbKQTRx (ORCPT ); Tue, 17 Nov 2015 14:17:53 -0500 Received: from mout.kundenserver.de ([217.72.192.73]:62372 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751822AbbKQTRv (ORCPT ); Tue, 17 Nov 2015 14:17:51 -0500 X-Greylist: delayed 8014 seconds by postgrey-1.27 at vger.kernel.org; Tue, 17 Nov 2015 14:17:51 EST From: Arnd Bergmann To: Will Deacon Cc: Catalin Marinas , kernel-build-reports@lists.linaro.org, olof@lixom.net, David Miller , eric.dumazet@gmail.com, netdev@vger.kernel.org, linux-next@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: next build: 235 warnings 3 failures (next/next-20151117) Date: Tue, 17 Nov 2015 20:17:17 +0100 Message-ID: <3723928.99NZh1TC6E@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: <20151117171236.GJ30101@arm.com> References: <564a9961.878b420a.331b8.fffffd62@mx.google.com> <6370082.rfihnaNWhf@wuerfel> <20151117171236.GJ30101@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:WGH/5fUmxzVz6Frz/0nclzlyRfQvyf/idlwKw77FqaljSteeO3y 1anfNdjO+j2cPkJq226PMKr9rcOF3fJI11Lf7E3aqiuT7SFhCducclExIL2eKGcaq2zait2 tapTw3M2rdBEEs5vcS2jL8CTYHDGZ77YP9L6N9DW/w8hcgqlJz1ZRWFpc+MRXJGS1cU3E+8 TucgxdZvgr9XYKTgzXHRA== X-UI-Out-Filterresults: notjunk:1;V01:K0:54T9SlMB4xM=:xRwNh+m40G9LrgFkjHcNOh d+QW8Qp75TVRdEYt8TowTMU9ss/NN94fBG6aP6YBOJTmz6/v+9IzZO+czASzT+qz6bprnoF7P lDV7B5i2eX/H3mf6N0CiYUmG+7xXY5y/IjJZIZ9s+BWkyVew9KI5S5YPjTjEa+v3xEx4o5DUg TjOMCn3o/LkTQROSTj8qyEVhMHsASKCuvYwCVb/k8ClINJWWs3rJC5cNxDfmQL8uzg6gST91g /u2w7XF/oAgg7VtQ5uVs2MYK/IyOmF1+urbHSZCjcJRWfDVQ4/kSq81Ec3sB27NOkCVqW0mof S2cR9pxXWmf8eTy/RFP74lhN+jWj/WLMGzbCU9HNxHgUC7p3MPBdS1Q5Fphz9Rt+gPUipAoyU NCy1lCAyyIQLI1sx3qmYV2njMwf1uPUTB5dliOyegnRHw1ZGoE7QBfyEoNVmKO/EhdRQ/U9m2 dtz7C1ufnF2/6i2+dyqmJJqmwobf49ExRuy5AbrTs7yr8lshRKg+QtJXjSOw8ICYtFPoIDXgo eIobFYSy8Dn8X1NG7gwHgDVPmyUSvXVlkg1TRSCUnGubk3a3ZOrbEQ6pE3UDjf2pC2dVFrCH0 wB/vkG7mlg1RztGVm8+kYRF5dLsYZxBOpOEQYKQuNiw/ntfJBaMh0ULLg34c+0j75mKgi24xX Xp5IKXqMN/bgtZi76MQ5m6mrdBrziju0AqE49fvhe+KaiwmGqcydSX4AFVhj+Bn7UkAqtphFf J9Ihoks5KlODyYgs Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday 17 November 2015 17:12:37 Will Deacon wrote: > On Tue, Nov 17, 2015 at 06:03:40PM +0100, Arnd Bergmann wrote: > > On Tuesday 17 November 2015 16:44:53 Will Deacon wrote: > > > > 8<---- > > > > Subject: ARM64: make smp_load_acquire() work with const arguments > > > > > > > > smp_load_acquire() uses typeof() to declare a local variable for temporarily > > > > storing the output of the memory access. This fails when the argument is > > > > constant, because the assembler complains about using a constant register > > > > as output: > > > > > > > > arch/arm64/include/asm/barrier.h:71:3: error: read-only variable '___p1' > > > > used as 'asm' output > > > > > > Do you know the usage in the kernel causing this warning? > > > > A newly introduced function in include/net/sock.h: > > > > static inline int sk_state_load(const struct sock *sk) > > { > > return smp_load_acquire(&sk->sk_state); > > } > > Hmm, maybe we could play a similar trick to READ_ONCE by declaring an > anonymous union and writing through the non-const member? Yes, I think that would work, if you think we need to care about the case where we read into a structure. Can you come up with a patch for that? Arnd