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 D1541EE499C for ; Wed, 11 Sep 2024 18:02:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=0ihUxWnJ1ESYco5Pe6kpjdBw8nJlk/3qj/ALs1xfzIA=; b=s0euQlJ39/SyIoxJdzxKwzmAhI D49AOdplecz9jwCjWaI/7C+n8RUJG0+pxEkfF2GLyyEKfCaQhZaBk/kPW+briTFNlAhH02w13sh0L usn3psG3w6CL8HdKoYPs0VrW8DWKAP4sAEOOOpLeiBvkJseYP5W6sukeGPHX5t5PXg6e2ZIljs7er ezQzE0zpdXq6jZdSdHm9HV9xgamyRweor1iimIF6/SDiyLC7OZU6x1Zav1IIFj5zOetS70wusy+tP QbGmlZ8ylmwFfainOaqGcD3tSVpbKOUM/2e5aaeznJSJBzcucCOWPzT8drH7Wr+pmxTx8XsrxY0yQ FeyMdmDw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1soRfc-0000000AaCa-3z07; Wed, 11 Sep 2024 18:02:25 +0000 Received: from out-182.mta1.migadu.com ([2001:41d0:203:375::b6]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1soRdY-0000000AZt2-2yVB for linux-arm-kernel@lists.infradead.org; Wed, 11 Sep 2024 18:00:18 +0000 Date: Wed, 11 Sep 2024 11:00:05 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1726077613; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=0ihUxWnJ1ESYco5Pe6kpjdBw8nJlk/3qj/ALs1xfzIA=; b=NA9D5xLd9af5GmohRLDHBX/ZD3NVd7AlhaZTqjyjEg8mJGwFv4ZsCJ+1CM3qgzlceWrf8L J/uEx+oZ9wy0Jw0FKSrCVgAm3JchXgWwSLiMX7x95t1U4ZnyMOQJHg74heIYduK+3WOMOX L1a5umMbadBCOtFfkKgP0GbmVHsFMRo= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Oliver Upton To: Marc Zyngier Cc: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, James Morse , Suzuki K Poulose , Zenghui Yu Subject: Re: [PATCH 0/3] KVM: arm64: Get rid of REG_HIDDEN_USER Message-ID: References: <20240904082419.1982402-1-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240904082419.1982402-1-maz@kernel.org> X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240911_110017_037435_FB759C46 X-CRM114-Status: GOOD ( 12.44 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Sep 04, 2024 at 09:24:16AM +0100, Marc Zyngier wrote: > REG_HIDDEN_USER was introduced as a way to deal with the ARMv8.3 flavour of > FEAT_NV, where most EL12 sysreg accesses would trap and yet be mapped to a > EL1 register (KVM doing in SW what FEAT_NV2 does in HW). This handling > imposed that the EL12 register shouldn't be visible to userspace, hence the > special REG_HIDDEN_USER visibility. > > Since 4d4f52052ba8 ("KVM: arm64: nv: Drop EL12 register traps that are > redirected to VNCR") and the admission that KVM would never be supporting > the original FEAT_NV, REG_HIDDEN_USER only had a few users, all of which > could either be replaced by a more ad-hoc mechanism, or removed altogether. > > This series goes ahead and cleans it up for good, removing a tiny bit of > unnecessary complexity. Yeah, let's toss it. Reviewed-by: Oliver Upton -- Thanks, Oliver