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 9497B174EEB; Thu, 1 Aug 2024 10:07:55 +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=1722506875; cv=none; b=ZmExBWe5zAR+cOGlD15LpPLHtdtwyCr2eziKpeXPsQXpO3LFwGDoJrAGKevmrCpspPjalQ1jx9h9/HFkiRDBMQ+5e28ncU3CdJP/2NfU66WPw7n6L4slDCggakecQmsgvz1klbeut+mIoNWePWB2lOcOl6jntmwcs4IrEBiHgW0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722506875; c=relaxed/simple; bh=1omcIl0ySlr8+5216FhuGPRNQkd7nfMr+PkPp6A7HmE=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=IIKOpcMyG9xy3Fj9vvkPaF3lDgbgN9Qjk1MNP7rz35ILJcWhVPtcOv9B+vjmJzt2+I+dwCQcQWXYCOYA6CIih2vioIrx+eO+V+/KQ4kaQQHwmZwDSOwSKsLqvN9weqigqU17pn1+9Nu00xrU7EmnhvTaZPI5zaEpA50GaX//ito= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dXl6XfVw; 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="dXl6XfVw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5F19EC32786; Thu, 1 Aug 2024 10:07:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722506875; bh=1omcIl0ySlr8+5216FhuGPRNQkd7nfMr+PkPp6A7HmE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=dXl6XfVwOB9GlSLpifm4SQnLN1SxN9WD5f/MTtx+7gzr1ecINtOADxIOmr8sjVBL0 DVMXHY/qfYmEhNan55mGOmG6D7THyLOPd70VPVKIpK/4MAQ5E5HS45NyBgeC5R48+X z9v7rywzNiMJ0Y3pLiLCJmKABr+FNbRPJFAyTyruso3jShF040qqp9MpwrWDsAtHKt fWTz+yRtpK8TbmWmQV9Ovzo1U3O3+yf5d0a9Gg2dNbSlY68eZRNVapCcFH1FcVxKAs Ludh8f3lr4RMdR6f7qJHOWB6bVOFl8ZRUulSkXqf7CV6Gn2MFS6IIw7ZvAl4rbJ8vr zHK3gmvw2IfAQ== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.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 1sZSiv-00HLX2-08; Thu, 01 Aug 2024 11:07:53 +0100 Date: Thu, 01 Aug 2024 11:07:52 +0100 Message-ID: <86plqs1rpj.wl-maz@kernel.org> From: Marc Zyngier To: Sean Christopherson , Steven Price Cc: Paolo Bonzini , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, David Matlack , David Stevens Subject: Re: [PATCH v12 01/84] KVM: arm64: Release pfn, i.e. put page, if copying MTE tags hits ZONE_DEVICE In-Reply-To: <20240726235234.228822-2-seanjc@google.com> References: <20240726235234.228822-1-seanjc@google.com> <20240726235234.228822-2-seanjc@google.com> 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/29.3 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: linux-mips@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: 185.219.108.64 X-SA-Exim-Rcpt-To: seanjc@google.com, steven.price@arm.com, pbonzini@redhat.com, oliver.upton@linux.dev, zhaotianrui@loongson.cn, maobibo@loongson.cn, chenhuacai@kernel.org, mpe@ellerman.id.au, anup@brainfault.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, borntraeger@linux.ibm.com, frankja@linux.ibm.com, imbrenda@linux.ibm.com, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, dmatlack@google.com, stevensd@chromium.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false + Steven Price for this patch (and the following one), as this really is his turf. On Sat, 27 Jul 2024 00:51:10 +0100, Sean Christopherson wrote: > > Put the page reference acquired by gfn_to_pfn_prot() if > kvm_vm_ioctl_mte_copy_tags() runs into ZONE_DEVICE memory. KVM's less- > than-stellar heuristics for dealing with pfn-mapped memory means that KVM > can get a page reference to ZONE_DEVICE memory. > > Fixes: f0376edb1ddc ("KVM: arm64: Add ioctl to fetch/store tags in a guest") > Signed-off-by: Sean Christopherson > --- > arch/arm64/kvm/guest.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c > index 11098eb7eb44..e1f0ff08836a 100644 > --- a/arch/arm64/kvm/guest.c > +++ b/arch/arm64/kvm/guest.c > @@ -1059,6 +1059,7 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, > page = pfn_to_online_page(pfn); > if (!page) { > /* Reject ZONE_DEVICE memory */ > + kvm_release_pfn_clean(pfn); > ret = -EFAULT; > goto out; > } > -- > 2.46.0.rc1.232.g9752f9e123-goog > > -- Without deviation from the norm, progress is not possible.