From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 47BA76A35A; Wed, 17 Apr 2024 07:51:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713340308; cv=none; b=hi9doASCU19cdraqFZvCVxC3ssePMxjSkwlsiWrrgUGkVGkIX6dtMzNWMKvBUcYo4Nc3+0hLzD5d1hKf/E1xNoZ1Rw8fOoLUs6h5YrQtJUBAxhAwX5ltOO7Ta5DzrgKx8glyXh0D9L8OfGuHee1D8TJuyLZYV7bi2fsZh/rMND8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713340308; c=relaxed/simple; bh=oDubD3s6K3Vp9t5I92UODI1kpQy++uUyuHq9AfWOrbE=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=VsihQmB7Ai8lGvkCymp9i42Q8ZEhaDjIt/jT+Ktvmd5HXT7NKm3KRKvTZaxRzUcgSy/DCqIwNgPTiHFDm9nTuIVAv66q1y+KiA1WM0PehboKUFxJINACWF5PYGXW+vymlSkIzjlQLcfS2fKjO4co8BA5wVkteP+HoDwRjCftKWk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GhZ6B9tn; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="GhZ6B9tn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCBDFC072AA; Wed, 17 Apr 2024 07:51:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713340307; bh=oDubD3s6K3Vp9t5I92UODI1kpQy++uUyuHq9AfWOrbE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=GhZ6B9tnE/ndzP+0tBZLh/KgM/KeNvAE5JbPs68UpOYwThywd0OzzhF3lAz4I9BbG Vsw6XMGkHp0Mvztg9iYRDAmh2PaoTVSzmiJEGPcmX/XzJYN+C9mt4KOKzt0WadXI6m gN/8TOxljxdP3HIJ55EKe9HaSeKUGBOO4eXGlxdyjLO9LgFwJ9nAke+E3xP/e/CViJ HHzFolrswKs8FvWzGkyHHdwFVhSozdDsBGzauMeiq6O1Itlt8MoCy37Z87wo1aMD6i qYqisOX7t/27oMAClsrpQzIe0fsZT6C8nqou5eR4h9GxZSJXUuZy2XaRBTnUW+Kn2N keMujT677CHoQ== Received: from ip-185-104-136-29.ptr.icomera.net ([185.104.136.29] helo=wait-a-minute.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1rx053-005HMD-CD; Wed, 17 Apr 2024 08:51:45 +0100 Date: Wed, 17 Apr 2024 08:51:42 +0100 Message-ID: <874jc0s9yp.wl-maz@kernel.org> From: Marc Zyngier To: Oliver Upton Cc: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, James Morse , Suzuki K Poulose , Zenghui Yu , Joey Gouly , Will Deacon , Catalin Marinas Subject: Re: [PATCH v3 04/15] KVM: arm64: nv: Drop VCPU_HYP_CONTEXT flag In-Reply-To: References: <20240321155356.3236459-1-maz@kernel.org> <20240321155356.3236459-5-maz@kernel.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/28.2 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.104.136.29 X-SA-Exim-Rcpt-To: oliver.upton@linux.dev, kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, joey.gouly@arm.com, will@kernel.org, catalin.marinas@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Tue, 16 Apr 2024 21:06:26 +0100, Oliver Upton wrote: > > On Thu, Mar 21, 2024 at 03:53:45PM +0000, Marc Zyngier wrote: > > diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c > > index 1581df6aec87..58415783fd53 100644 > > --- a/arch/arm64/kvm/hyp/vhe/switch.c > > +++ b/arch/arm64/kvm/hyp/vhe/switch.c > > @@ -197,7 +197,7 @@ static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code) > > * If we were in HYP context on entry, adjust the PSTATE view > > * so that the usual helpers work correctly. > > */ > > - if (unlikely(vcpu_get_flag(vcpu, VCPU_HYP_CONTEXT))) { > > + if (unlikely(read_sysreg(hcr_el2) & HCR_NV)) { > > Can this be additionally predicated on vcpu_has_nv() so we condition on > the NV cpucap and avoid the sysreg read on non-nesting hardware? Yup, good call. I'll add that. Thanks, M. -- Without deviation from the norm, progress is not possible.