From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 70883C48BE6 for ; Wed, 16 Jun 2021 18:54:39 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 367BC613BD for ; Wed, 16 Jun 2021 18:54:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 367BC613BD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:From:References:Cc:To:Subject:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=FGSZ6Gxldi7evXyB/H5k8kF/TsS6fIhF71PZh6XThME=; b=2afBOatwlpZI1YghkH+kAXOXXs Ic8MjIzPcTiELvtSXkklWDXZifzN1Nm/Qiax079f7y+1Bsv3FJe9RJF4/QthRg5xUfGPpVq/GAsRs eXVWy6aVk52l32aNi6LdlWZqEdISXpG3pJaWj6pMk+MW2fG6vbruYhm2MVTsWa073BLpEI/7dPIJi +rQR4AGuDF4EkT4boGymE0ORaQi5ivQsA9JltniH3y6uCI5qN8z+RDM1VlnBeL+8kWtuWlNM92idi cTjp/6JZySIsAyyBdCX32/KW+7lRbu/eWHvW52vUlXcgy2OLEaLl1MGtM3rWsYXUU8lvtsC0phzil VKuTXlYw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ltaeu-007SYW-Qn; Wed, 16 Jun 2021 18:53:04 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ltaep-007SWw-Pk for linux-arm-kernel@lists.infradead.org; Wed, 16 Jun 2021 18:53:02 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id E38DA613B4; Wed, 16 Jun 2021 18:52:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623869579; bh=Yqry3gXTN7L5llHGJ5LYioszkeOqgnImNugNlvlJamM=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=ZdUJ7KXNhkuKNAUX1x7Dbc4PeUFd1RBBDmKso0XmPrKjdsmddGAwUrigYr/JM82Wg QZYY1HboE2uqd3aDHbef4mKiID3gsuvm5EVze2dABZvbyZheNWkpSQusDL9vvTKeTZ llgpyzsvBgZGHBlVCUTvm9DEzi6Hvbi5dJZInB6zEXy5rjMxcXqZdGesyqHMQpTlGH 9vnvX5X6f8YAkbV0xff+6rjr3kuqkpugsrxF/ZBh7JF/BjFyZohG2TevhZq78dCe75 ZbfCX4ngCfJiMjfS5mqXkORZczgWyrHbvJC4IDDJol6JXrj9FBaLWKtCUNktRtFrtB Ewqj3p90Zv/OQ== Subject: Re: [PATCH 8/8] membarrier: Rewrite sync_core_before_usermode() and improve documentation To: Nicholas Piggin , x86@kernel.org Cc: Andrew Morton , Benjamin Herrenschmidt , Catalin Marinas , Dave Hansen , linux-arm-kernel@lists.infradead.org, LKML , linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, Mathieu Desnoyers , Michael Ellerman , Paul Mackerras , Peter Zijlstra , stable@vger.kernel.org, Will Deacon References: <07a8b963002cb955b7516e61bad19514a3acaa82.1623813516.git.luto@kernel.org> <1623818343.eko1v01gvr.astroid@bobo.none> From: Andy Lutomirski Message-ID: <1e248763-9372-6e4e-5dea-cda999000aeb@kernel.org> Date: Wed, 16 Jun 2021 11:52:58 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <1623818343.eko1v01gvr.astroid@bobo.none> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210616_115259_957667_C091F5B5 X-CRM114-Status: GOOD ( 13.26 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 6/15/21 9:45 PM, Nicholas Piggin wrote: > Excerpts from Andy Lutomirski's message of June 16, 2021 1:21 pm: >> The old sync_core_before_usermode() comments suggested that a non-icache-syncing >> return-to-usermode instruction is x86-specific and that all other >> architectures automatically notice cross-modified code on return to >> userspace. >> +/* >> + * XXX: can a powerpc person put an appropriate comment here? >> + */ >> +static inline void membarrier_sync_core_before_usermode(void) >> +{ >> +} >> + >> +#endif /* _ASM_POWERPC_SYNC_CORE_H */ > > powerpc's can just go in asm/membarrier.h $ ls arch/powerpc/include/asm/membarrier.h ls: cannot access 'arch/powerpc/include/asm/membarrier.h': No such file or directory > > /* > * The RFI family of instructions are context synchronising, and > * that is how we return to userspace, so nothing is required here. > */ Thanks! _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel