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 BF286C61DA4 for ; Sat, 11 Feb 2023 18:18:32 +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=4PwB+Lr3IfOb6EtzLAdRuQSm6MeQR1gEoaM8XbsE49M=; b=lPqroZRrdgPG0y kkxuQ/j04btV+fCKDuPoPBXvSORNS3aQFr7tV4UPSs7QK5SFqCP0/AyeC903U8LZWJosL+ziNNWBG vWIZ4QXeYZzuhzyZPERJhsEND4kFoDxjpTGgfj0YuAUgxA5frBdegnHU5cI+0h5xjcutSc6E56unr /dO2igz6lBX9F2gLx6G5ESA67qG8Lhl2Y6Zyj4y+sNVkxbcD2W5+fSFFocS+bUVQpVHQ3VH1GES+9 +op00kvMKJUXX0B8YHECwqozL0uQD6WbjhKoV4tHp31iKVoi1cAEA57F0WCFaY0u8dnVDy2ELpMHn h/lEkdZZbwCQ0Yz6dtiQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pQuRC-00A3wV-9d; Sat, 11 Feb 2023 18:17:26 +0000 Received: from out-221.mta1.migadu.com ([2001:41d0:203:375::dd]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pQuR3-00A3vm-VA for linux-arm-kernel@lists.infradead.org; Sat, 11 Feb 2023 18:17:24 +0000 Date: Sat, 11 Feb 2023 18:17:09 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1676139434; 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=N/Pf/v0NdU3twhv11oRMVuPWRZtmDGxVoirpuiLBTZ8=; b=Dch6PBorZoikpEn6EhKqUV76zHIfzbrZpfj4oEbDafVGoF9818U1pDyhk3QL3RVxXZmNOt BYunCGOM287GPH8ZdVbTEdFPtNY69aonM1bchy7O1c0UNnQvaohuQGQ0FyQ/p6TQ64qXaJ vNlyzKHB2Z2MJaKGXPboNTFLdAn+4Xs= 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, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Alexandru Elisei , Andre Przywara , Catalin Marinas , Christoffer Dall , Ganapatrao Kulkarni , Russell King , James Morse , Suzuki K Poulose , Zenghui Yu Subject: Re: [PATCH 12/18] KVM: arm64: nv: Handle PSCI call via smc from the guest Message-ID: References: <20230209175820.1939006-1-maz@kernel.org> <20230209175820.1939006-13-maz@kernel.org> <87pmaglcgw.wl-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <87pmaglcgw.wl-maz@kernel.org> X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230211_101723_167033_07DEC473 X-CRM114-Status: GOOD ( 12.01 ) 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 Sat, Feb 11, 2023 at 10:31:59AM +0000, Marc Zyngier wrote: > On Sat, 11 Feb 2023 10:07:41 +0000, Oliver Upton wrote: [...] > > This also has the subtle effect of allowing smc instructions from a > > non-nested guest to hit our hypercall surface too. > > I think we'll have to eventually allow that (see the TRNG spec which > we blatantly deviate from by requiring an HVC), but we don't have to > cross that bridge just yet. Perhaps I'll continue to bury my head in the sand and act like you didn't say that :) I seem to recall that the SMCCC suggests either the SMC or HVC instruction could be used if both EL2 and EL3 are implemented. So we've messed that up too. My only worry is if we open up the use of SMCs and userspace does something silly in ACPI/DT and unconditionally picks SMCs over HVCs. The VM won't get far on pre-NV hardware w/o EL3... We could always just hide the presence of EL3 for non-NV guests :) -- Thanks, Oliver _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel