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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 9F507C28B2B for ; Wed, 17 Aug 2022 14:29:34 +0000 (UTC) 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:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=VS1jap52yOGSjRgWKN3upwKwgMd/G+FnoqQz6w5FOgE=; b=cZbJl0KjJ5Vmv1 HJjlBye4RQXRjTOEVLwrVYHDLES/qf77eTsvfmUoQM/y1nY78L/0u2kVXT1W6g5aLvzm1JmTlSN/y nZpoqtdyCERCoJZexJg5wMmg+8w1UQpZJT4i5wDQQ/UA+9yg6UCJNeihE4yIYOBc84GlU3R1/zanf sWFk3PTCZuTv58RZFrawsGtlVnecV42FCGjxb8vEJkFLUlccSdnB9hoUT5Glhb4/GzZZxSnr0Iq1V eE8avBGWQzX23lA7WpbD864yHv5hvNm5XKrDRqJrk6ERdnNYVfd/niZMoBwfQNZVy9XuEbJ/PsB40 7/WkGy4fjlDO0Y68lWGA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oOK1z-002poY-J0; Wed, 17 Aug 2022 14:28:27 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oOK1w-002pmd-6A for linux-arm-kernel@lists.infradead.org; Wed, 17 Aug 2022 14:28:25 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BED296142A for ; Wed, 17 Aug 2022 14:28:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 78461C433C1; Wed, 17 Aug 2022 14:28:22 +0000 (UTC) Date: Wed, 17 Aug 2022 15:28:19 +0100 From: Catalin Marinas To: Mark Brown Cc: Will Deacon , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 4/4] arm64/sme: Don't flush SVE register state when handling SME traps Message-ID: References: <20220815132834.229769-1-broonie@kernel.org> <20220815132834.229769-5-broonie@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220815132834.229769-5-broonie@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220817_072824_331275_0962C5A1 X-CRM114-Status: GOOD ( 14.34 ) 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 Mon, Aug 15, 2022 at 02:28:34PM +0100, Mark Brown wrote: > Currently as part of handling a SME access trap we flush the SVE register > state. This is not needed and would corrupt register state if the task has > access to the SVE registers already. For non-streaming mode accesses the > required flushing will be done in the SVE access trap. For streaming > mode SVE register accesses the architecture guarantees that the register > state will be flushed when streaming mode is entered or exited so there is > no need for us to do so. Simply remove the register initialisation. > > Fixes: 8bd7f91c03d88 ("arm64/sme: Implement traps and syscall handling for SME") > Signed-off-by: Mark Brown Reviewed-by: Catalin Marinas _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel