From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH v7 4/4] KVM: arm64/mmu: count KVM s2 mmu usage in secondary pagetable stats Date: Wed, 24 Aug 2022 15:24:57 +0100 Message-ID: <87zgftra6e.wl-maz@kernel.org> References: <20220823004639.2387269-1-yosryahmed@google.com> <20220823004639.2387269-5-yosryahmed@google.com> <319904e0-3722-8ab1-cf74-491b9c32e23b@arm.com> Mime-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1661351108; bh=GlyJJ9dV5dcNN4e8F/+zW4aKoVpKrRpQG5FduS6xj60=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=RlOFCFyOYvgDsmtvh7bI4fnzpALdN2M/t7Sdx3OBkKjuNIOEGaxCSeasH5M/MQcVu 39MlyXzAx5P4sTw6vHcANvoZt5XNpo4DlF7c3sYHlUc18EhnOJ+Nx/MvsFzgmvBHY4 mnjdD22AawdV/zG7YInQPGZCdQ59QpasRPsWlEDIns2MvGoYCbBB1Zlc8Zx17VlJKx WlpiSr2SvuWNUu+CiU1aCrccEOnvIj7LHy6SiOm7h2HB/+9dhcnJIKX7ihFSu2bagl 8lmZ+3PVbzSvTHGsjmudsOHkifF0MknUFCc1OryZ69NDWLBrFdNJWFGyy08RVV1UqF GXox+Ellgocog== In-Reply-To: <319904e0-3722-8ab1-cf74-491b9c32e23b@arm.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Ryan Roberts Cc: Wanpeng Li , kvm@vger.kernel.org, Roman Gushchin , Michal Hocko , Shaoqin , linux-mm@kvack.org, Zefan Li , kvmarm@lists.cs.columbia.edu, Joerg Roedel , Shakeel Butt , cgroups@vger.kernel.org, nd@arm.com, Huang@google.com, linux-arm-kernel@lists.infradead.org, Jim Mattson , Yosry Ahmed , Andrew Morton , linux-kernel@vger.kernel.org, Johannes Weiner , Tejun Heo , Paolo Bonzini , Vitaly Kuznetsov On Wed, 24 Aug 2022 14:43:43 +0100, Ryan Roberts wrote: > > > Count the pages used by KVM in arm64 for stage2 mmu in memory stats > > under secondary pagetable stats (e.g. "SecPageTables" in /proc/meminfo) > > to give better visibility into the memory consumption of KVM mmu in a > > similar way to how normal user page tables are accounted. > > > > Signed-off-by: Yosry Ahmed > > Reviewed-by: Oliver Upton > > Reviewed-by: Marc Zyngier > > --- > > I see that you are not including the memory reserved for the host > stage2 table when using protected KVM. Is this something worth adding? > (See arch/arm64/kvm/pkvm.c:kvm_hyp_reserve()). > > This reservation is done pretty early on in bootmem_init() so not sure > if this could cause some init ordering issues that might be tricky to > solve though. I also don't see what this buys us. This memory can't be reclaimed, and is not part of KVM's job for the purpose of running guests, which is what this series is about. If anything, it should be accounted separately. M. -- Without deviation from the norm, progress is not possible. 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 mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9EF65C00140 for ; Wed, 24 Aug 2022 14:25:18 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id D740A4CFB7; Wed, 24 Aug 2022 10:25:17 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id zp+6CChK5-kY; Wed, 24 Aug 2022 10:25:13 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 9DDCA4D049; Wed, 24 Aug 2022 10:25:13 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id E162D4CFAB for ; 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b=RlOFCFyOYvgDsmtvh7bI4fnzpALdN2M/t7Sdx3OBkKjuNIOEGaxCSeasH5M/MQcVu 39MlyXzAx5P4sTw6vHcANvoZt5XNpo4DlF7c3sYHlUc18EhnOJ+Nx/MvsFzgmvBHY4 mnjdD22AawdV/zG7YInQPGZCdQ59QpasRPsWlEDIns2MvGoYCbBB1Zlc8Zx17VlJKx WlpiSr2SvuWNUu+CiU1aCrccEOnvIj7LHy6SiOm7h2HB/+9dhcnJIKX7ihFSu2bagl 8lmZ+3PVbzSvTHGsjmudsOHkifF0MknUFCc1OryZ69NDWLBrFdNJWFGyy08RVV1UqF GXox+Ellgocog== Received: from [12.191.126.171] (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 1oQrJa-005SYH-2A; Wed, 24 Aug 2022 15:25:06 +0100 Date: Wed, 24 Aug 2022 15:24:57 +0100 Message-ID: <87zgftra6e.wl-maz@kernel.org> From: Marc Zyngier To: Ryan Roberts Subject: Re: [PATCH v7 4/4] KVM: arm64/mmu: count KVM s2 mmu usage in secondary pagetable stats In-Reply-To: <319904e0-3722-8ab1-cf74-491b9c32e23b@arm.com> References: <20220823004639.2387269-1-yosryahmed@google.com> <20220823004639.2387269-5-yosryahmed@google.com> <319904e0-3722-8ab1-cf74-491b9c32e23b@arm.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/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") X-SA-Exim-Connect-IP: 12.191.126.171 X-SA-Exim-Rcpt-To: ryan.roberts@arm.com, yosryahmed@google.com, tj@kernel.org, hannes@cmpxchg.org, lizefan.x@bytedance.com, james.morse@arm.com, alexandru.elisei@arm.com, suzuki.poulose@arm.com, pbonzini@redhat.com, seanjc@google.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org, akpm@linux-foundation.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, oupton@google.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Huang@google.com, shaoqin.huang@intel.com, linux-mm@kvack.org, cgroups@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, nd@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Cc: Wanpeng Li , kvm@vger.kernel.org, Roman Gushchin , Michal Hocko , Shaoqin , linux-mm@kvack.org, Zefan Li , kvmarm@lists.cs.columbia.edu, Joerg Roedel , Shakeel Butt , cgroups@vger.kernel.org, nd@arm.com, Huang@google.com, linux-arm-kernel@lists.infradead.org, Jim Mattson , Yosry Ahmed , Andrew Morton , linux-kernel@vger.kernel.org, Johannes Weiner , Tejun Heo , Paolo Bonzini , Vitaly Kuznetsov X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On Wed, 24 Aug 2022 14:43:43 +0100, Ryan Roberts wrote: > > > Count the pages used by KVM in arm64 for stage2 mmu in memory stats > > under secondary pagetable stats (e.g. "SecPageTables" in /proc/meminfo) > > to give better visibility into the memory consumption of KVM mmu in a > > similar way to how normal user page tables are accounted. > > > > Signed-off-by: Yosry Ahmed > > Reviewed-by: Oliver Upton > > Reviewed-by: Marc Zyngier > > --- > > I see that you are not including the memory reserved for the host > stage2 table when using protected KVM. Is this something worth adding? > (See arch/arm64/kvm/pkvm.c:kvm_hyp_reserve()). > > This reservation is done pretty early on in bootmem_init() so not sure > if this could cause some init ordering issues that might be tricky to > solve though. I also don't see what this buys us. This memory can't be reclaimed, and is not part of KVM's job for the purpose of running guests, which is what this series is about. If anything, it should be accounted separately. M. -- Without deviation from the norm, progress is not possible. _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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 AE3D9C00140 for ; Wed, 24 Aug 2022 14:26:17 +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:MIME-Version:References:In-Reply-To: Subject:Cc:To:From:Message-ID:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; 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Wed, 24 Aug 2022 14:25:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B45EEC433C1; Wed, 24 Aug 2022 14:25:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1661351108; bh=GlyJJ9dV5dcNN4e8F/+zW4aKoVpKrRpQG5FduS6xj60=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=RlOFCFyOYvgDsmtvh7bI4fnzpALdN2M/t7Sdx3OBkKjuNIOEGaxCSeasH5M/MQcVu 39MlyXzAx5P4sTw6vHcANvoZt5XNpo4DlF7c3sYHlUc18EhnOJ+Nx/MvsFzgmvBHY4 mnjdD22AawdV/zG7YInQPGZCdQ59QpasRPsWlEDIns2MvGoYCbBB1Zlc8Zx17VlJKx WlpiSr2SvuWNUu+CiU1aCrccEOnvIj7LHy6SiOm7h2HB/+9dhcnJIKX7ihFSu2bagl 8lmZ+3PVbzSvTHGsjmudsOHkifF0MknUFCc1OryZ69NDWLBrFdNJWFGyy08RVV1UqF GXox+Ellgocog== Received: from [12.191.126.171] (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 1oQrJa-005SYH-2A; Wed, 24 Aug 2022 15:25:06 +0100 Date: Wed, 24 Aug 2022 15:24:57 +0100 Message-ID: <87zgftra6e.wl-maz@kernel.org> From: Marc Zyngier To: Ryan Roberts Cc: Yosry Ahmed , Tejun Heo , Johannes Weiner , Zefan Li , James Morse , Alexandru Elisei , Suzuki K Poulose , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Andrew Morton , Michal Hocko , Roman Gushchin , Shakeel Butt , Oliver Upton , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Huang@google.com, Shaoqin , linux-mm@kvack.org, cgroups@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, nd@arm.com Subject: Re: [PATCH v7 4/4] KVM: arm64/mmu: count KVM s2 mmu usage in secondary pagetable stats In-Reply-To: <319904e0-3722-8ab1-cf74-491b9c32e23b@arm.com> References: <20220823004639.2387269-1-yosryahmed@google.com> <20220823004639.2387269-5-yosryahmed@google.com> <319904e0-3722-8ab1-cf74-491b9c32e23b@arm.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/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") X-SA-Exim-Connect-IP: 12.191.126.171 X-SA-Exim-Rcpt-To: ryan.roberts@arm.com, yosryahmed@google.com, tj@kernel.org, hannes@cmpxchg.org, lizefan.x@bytedance.com, james.morse@arm.com, alexandru.elisei@arm.com, suzuki.poulose@arm.com, pbonzini@redhat.com, seanjc@google.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org, akpm@linux-foundation.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, oupton@google.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Huang@google.com, shaoqin.huang@intel.com, linux-mm@kvack.org, cgroups@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, nd@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220824_072511_879978_F2048797 X-CRM114-Status: GOOD ( 20.86 ) 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 Wed, 24 Aug 2022 14:43:43 +0100, Ryan Roberts wrote: > > > Count the pages used by KVM in arm64 for stage2 mmu in memory stats > > under secondary pagetable stats (e.g. "SecPageTables" in /proc/meminfo) > > to give better visibility into the memory consumption of KVM mmu in a > > similar way to how normal user page tables are accounted. > > > > Signed-off-by: Yosry Ahmed > > Reviewed-by: Oliver Upton > > Reviewed-by: Marc Zyngier > > --- > > I see that you are not including the memory reserved for the host > stage2 table when using protected KVM. Is this something worth adding? > (See arch/arm64/kvm/pkvm.c:kvm_hyp_reserve()). > > This reservation is done pretty early on in bootmem_init() so not sure > if this could cause some init ordering issues that might be tricky to > solve though. I also don't see what this buys us. This memory can't be reclaimed, and is not part of KVM's job for the purpose of running guests, which is what this series is about. If anything, it should be accounted separately. M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4530AC32793 for ; Wed, 24 Aug 2022 14:25:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239142AbiHXOZT (ORCPT ); Wed, 24 Aug 2022 10:25:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42926 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239157AbiHXOZM (ORCPT ); Wed, 24 Aug 2022 10:25:12 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4050BF6C; Wed, 24 Aug 2022 07:25:09 -0700 (PDT) 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 6268D6181B; Wed, 24 Aug 2022 14:25:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B45EEC433C1; Wed, 24 Aug 2022 14:25:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1661351108; bh=GlyJJ9dV5dcNN4e8F/+zW4aKoVpKrRpQG5FduS6xj60=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=RlOFCFyOYvgDsmtvh7bI4fnzpALdN2M/t7Sdx3OBkKjuNIOEGaxCSeasH5M/MQcVu 39MlyXzAx5P4sTw6vHcANvoZt5XNpo4DlF7c3sYHlUc18EhnOJ+Nx/MvsFzgmvBHY4 mnjdD22AawdV/zG7YInQPGZCdQ59QpasRPsWlEDIns2MvGoYCbBB1Zlc8Zx17VlJKx WlpiSr2SvuWNUu+CiU1aCrccEOnvIj7LHy6SiOm7h2HB/+9dhcnJIKX7ihFSu2bagl 8lmZ+3PVbzSvTHGsjmudsOHkifF0MknUFCc1OryZ69NDWLBrFdNJWFGyy08RVV1UqF GXox+Ellgocog== Received: from [12.191.126.171] (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 1oQrJa-005SYH-2A; Wed, 24 Aug 2022 15:25:06 +0100 Date: Wed, 24 Aug 2022 15:24:57 +0100 Message-ID: <87zgftra6e.wl-maz@kernel.org> From: Marc Zyngier To: Ryan Roberts Cc: Yosry Ahmed , Tejun Heo , Johannes Weiner , Zefan Li , James Morse , Alexandru Elisei , Suzuki K Poulose , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Andrew Morton , Michal Hocko , Roman Gushchin , Shakeel Butt , Oliver Upton , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Huang@google.com, Shaoqin , linux-mm@kvack.org, cgroups@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, nd@arm.com Subject: Re: [PATCH v7 4/4] KVM: arm64/mmu: count KVM s2 mmu usage in secondary pagetable stats In-Reply-To: <319904e0-3722-8ab1-cf74-491b9c32e23b@arm.com> References: <20220823004639.2387269-1-yosryahmed@google.com> <20220823004639.2387269-5-yosryahmed@google.com> <319904e0-3722-8ab1-cf74-491b9c32e23b@arm.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/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 12.191.126.171 X-SA-Exim-Rcpt-To: ryan.roberts@arm.com, yosryahmed@google.com, tj@kernel.org, hannes@cmpxchg.org, lizefan.x@bytedance.com, james.morse@arm.com, alexandru.elisei@arm.com, suzuki.poulose@arm.com, pbonzini@redhat.com, seanjc@google.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org, akpm@linux-foundation.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, oupton@google.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Huang@google.com, shaoqin.huang@intel.com, linux-mm@kvack.org, cgroups@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, nd@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, 24 Aug 2022 14:43:43 +0100, Ryan Roberts wrote: > > > Count the pages used by KVM in arm64 for stage2 mmu in memory stats > > under secondary pagetable stats (e.g. "SecPageTables" in /proc/meminfo) > > to give better visibility into the memory consumption of KVM mmu in a > > similar way to how normal user page tables are accounted. > > > > Signed-off-by: Yosry Ahmed > > Reviewed-by: Oliver Upton > > Reviewed-by: Marc Zyngier > > --- > > I see that you are not including the memory reserved for the host > stage2 table when using protected KVM. Is this something worth adding? > (See arch/arm64/kvm/pkvm.c:kvm_hyp_reserve()). > > This reservation is done pretty early on in bootmem_init() so not sure > if this could cause some init ordering issues that might be tricky to > solve though. I also don't see what this buys us. This memory can't be reclaimed, and is not part of KVM's job for the purpose of running guests, which is what this series is about. If anything, it should be accounted separately. M. -- Without deviation from the norm, progress is not possible.