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[34.125.103.223]) by smtp.gmail.com with ESMTPSA id n6-20020a170902e54600b00173cfaed233sm659052plf.62.2022.09.07.14.47.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Sep 2022 14:47:14 -0700 (PDT) Date: Wed, 7 Sep 2022 14:47:08 -0700 From: David Matlack To: Oliver Upton Subject: Re: [PATCH 08/14] KVM: arm64: Protect page table traversal with RCU Message-ID: References: <20220830194132.962932-1-oliver.upton@linux.dev> <20220830194132.962932-9-oliver.upton@linux.dev> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220830194132.962932-9-oliver.upton@linux.dev> X-Mailman-Approved-At: Thu, 08 Sep 2022 04:34:28 -0400 Cc: kvm@vger.kernel.org, Marc Zyngier , linux-kernel@vger.kernel.org, Catalin Marinas , Ben Gardon , Paolo Bonzini , Will Deacon , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org 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 Tue, Aug 30, 2022 at 07:41:26PM +0000, Oliver Upton wrote: > The use of RCU is necessary to change the paging structures in parallel. > Acquire and release an RCU read lock when traversing the page tables. > > Signed-off-by: Oliver Upton > --- > arch/arm64/include/asm/kvm_pgtable.h | 19 ++++++++++++++++++- > arch/arm64/kvm/hyp/pgtable.c | 7 ++++++- > 2 files changed, 24 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h > index 78fbb7be1af6..7d2de0a98ccb 100644 > --- a/arch/arm64/include/asm/kvm_pgtable.h > +++ b/arch/arm64/include/asm/kvm_pgtable.h > @@ -578,9 +578,26 @@ enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte); > */ > enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte); > > +#if defined(__KVM_NVHE_HYPERVISOR___) > + Future readers will wonder why NVHE stubs out RCU support and how that is even correct. Some comments here would be useful explain it. > +static inline void kvm_pgtable_walk_begin(void) {} > +static inline void kvm_pgtable_walk_end(void) {} > + > +#define kvm_dereference_ptep rcu_dereference_raw How does NVHE have access rcu_dereference_raw()? > + > +#else /* !defined(__KVM_NVHE_HYPERVISOR__) */ > + > +#define kvm_pgtable_walk_begin rcu_read_lock > +#define kvm_pgtable_walk_end rcu_read_unlock > +#define kvm_dereference_ptep rcu_dereference > + > +#endif /* defined(__KVM_NVHE_HYPERVISOR__) */ > + > static inline kvm_pte_t kvm_pte_read(kvm_pte_t *ptep) > { > - return READ_ONCE(*ptep); > + kvm_pte_t __rcu *p = (kvm_pte_t __rcu *)ptep; > + > + return READ_ONCE(*kvm_dereference_ptep(p)); What about all the other places where page table memory is accessed? If RCU is going to be used to protect page table memory, then all accesses have to go under an RCU critical section. This means that page table memory should only be accessed through __rcu annotated pointers and dereferenced with rcu_dereference(). > } > > #endif /* __ARM64_KVM_PGTABLE_H__ */ > diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c > index f911509e6512..215a14c434ed 100644 > --- a/arch/arm64/kvm/hyp/pgtable.c > +++ b/arch/arm64/kvm/hyp/pgtable.c > @@ -284,8 +284,13 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, > .end = PAGE_ALIGN(walk_data.addr + size), > .walker = walker, > }; > + int r; > > - return _kvm_pgtable_walk(&walk_data); > + kvm_pgtable_walk_begin(); > + r = _kvm_pgtable_walk(&walk_data); > + kvm_pgtable_walk_end(); > + > + return r; > } > > struct leaf_walk_data { > -- > 2.37.2.672.g94769d06f0-goog > _______________________________________________ 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 172D8C38145 for ; Wed, 7 Sep 2022 21:49:20 +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=H6XaA8+mBqVopsPTNoKC2l5KM8GboSF+o5G5baNGKXo=; b=pFXNI7UPfApkG+ YkX3eqxueYGtxRqfo+I7zj1BEixjAxW1ssDMsKxSJCKCgHDFHWC+7yP9JV8vZfJf7o25S7gx9XH5h FgNuCuGbSxyseVl49UgazTAhoFVbrFdjrTJZKR3Bduqg6tucmD67ILeaFKo6Kv06v4AD2oFF3HcZ8 sgf7VTfHn94iP+2XmGUvVyekyqZcj2kX++HeHaFej584L1Jdt4ytVK+U9r0ai0NIZ4VmEKO5lqKNr IV1PWZBuJyytsl2QZpDKhOBhCFenHpgm5yUfEYhQefMDeJDSqnRXh6f8EncoDFKXraGbTFryxO2cu ZVrR746DgCjTvyOEvQrw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oW2tG-00ACOg-0o; Wed, 07 Sep 2022 21:47:22 +0000 Received: from mail-pl1-x633.google.com ([2607:f8b0:4864:20::633]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oW2tB-00ACL1-Tl for linux-arm-kernel@lists.infradead.org; Wed, 07 Sep 2022 21:47:19 +0000 Received: by mail-pl1-x633.google.com with SMTP id u22so15852163plq.12 for ; Wed, 07 Sep 2022 14:47:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date; bh=a0onBmXPphYT3RuqfDE1tfHpBM48udC3uDDfIPbNeqQ=; b=qz8qKS17YDB74dB3eVq/ImHb/1panXWt9MKNv77sjzlXj8cL3XwLCX/xz8ZQn9FJSc pkuvn/eM3SPKQUCBDgtCZu6rnvnlsgeB696oCeiPN8LzQIFq4odPuYBB/o7hizZaRcRP tH7JasNxHZyEVsUyfz0V/dL1r9OPMoCaBwGTkGjH1jd/RD5/uG56v/Pc1g6Dr4EGnH6r hr+0E5wBEw/x3ik8lSEvklHAQ6eORvUgxri4N5u/Sr7xvTrdNUpSsXg71MROLD6JhtYd nyD3JCmVLfqxQWXd75Tk6Z+u4KPOxj45s6/oI+dRFkvHvvGKtM9qmtSw3qCoO59EWNNk GKXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date; bh=a0onBmXPphYT3RuqfDE1tfHpBM48udC3uDDfIPbNeqQ=; b=5z5vrJfbCuDvacgKVv2h5jRHNS329ZndiiY8TPJV/IrqhJYyTYVbS/D/OWE/qqVlvl DTt9zTPesRPDSSF25VSr9w3u4axhZ9unTR1MblyTARWqhPu/7Y0BOd8XNIq1LTQRK4Dg lP4s7lLpsx1Q0/JHg8+FKfS1v2RmyutSVv/GiEZMXEM+l2upITrohvo07Andhpo+6586 9o5aiOw2rtobVJ0NMGGhUnHVlJr1RK4m1F2e6PBCF0FVSps14VPUz69uLASGcpc618NH qaT1sl14UJdQivTJT1QTpRg1EJ+9jjhVDXtl4QKnIqrG1k/95u4UA4gSkTu5vSKsWK4F fyIQ== X-Gm-Message-State: ACgBeo0INsfzMeqeUYV/0ZTj9tRIYpjpgbnwfahsecDxK57YOUiqRBsZ tr47fIg8eBFsqJA3mmiITsvfGw== X-Google-Smtp-Source: AA6agR7u55ulppnpFE92xnBEjpQea4OXXBFThe+B3Pt6YcvMkX+Mwtq2DlhDFlWJGj73EGApy3OVsw== X-Received: by 2002:a17:902:6b4c:b0:171:38ab:e762 with SMTP id g12-20020a1709026b4c00b0017138abe762mr5635735plt.42.1662587235722; Wed, 07 Sep 2022 14:47:15 -0700 (PDT) Received: from google.com (223.103.125.34.bc.googleusercontent.com. [34.125.103.223]) by smtp.gmail.com with ESMTPSA id n6-20020a170902e54600b00173cfaed233sm659052plf.62.2022.09.07.14.47.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Sep 2022 14:47:14 -0700 (PDT) Date: Wed, 7 Sep 2022 14:47:08 -0700 From: David Matlack To: Oliver Upton Cc: Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , Catalin Marinas , Will Deacon , Quentin Perret , Ricardo Koller , Reiji Watanabe , Ben Gardon , Paolo Bonzini , Gavin Shan , Peter Xu , Sean Christopherson , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 08/14] KVM: arm64: Protect page table traversal with RCU Message-ID: References: <20220830194132.962932-1-oliver.upton@linux.dev> <20220830194132.962932-9-oliver.upton@linux.dev> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220830194132.962932-9-oliver.upton@linux.dev> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220907_144718_016585_0AB1BB46 X-CRM114-Status: GOOD ( 23.56 ) 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 Tue, Aug 30, 2022 at 07:41:26PM +0000, Oliver Upton wrote: > The use of RCU is necessary to change the paging structures in parallel. > Acquire and release an RCU read lock when traversing the page tables. > > Signed-off-by: Oliver Upton > --- > arch/arm64/include/asm/kvm_pgtable.h | 19 ++++++++++++++++++- > arch/arm64/kvm/hyp/pgtable.c | 7 ++++++- > 2 files changed, 24 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h > index 78fbb7be1af6..7d2de0a98ccb 100644 > --- a/arch/arm64/include/asm/kvm_pgtable.h > +++ b/arch/arm64/include/asm/kvm_pgtable.h > @@ -578,9 +578,26 @@ enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte); > */ > enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte); > > +#if defined(__KVM_NVHE_HYPERVISOR___) > + Future readers will wonder why NVHE stubs out RCU support and how that is even correct. Some comments here would be useful explain it. > +static inline void kvm_pgtable_walk_begin(void) {} > +static inline void kvm_pgtable_walk_end(void) {} > + > +#define kvm_dereference_ptep rcu_dereference_raw How does NVHE have access rcu_dereference_raw()? > + > +#else /* !defined(__KVM_NVHE_HYPERVISOR__) */ > + > +#define kvm_pgtable_walk_begin rcu_read_lock > +#define kvm_pgtable_walk_end rcu_read_unlock > +#define kvm_dereference_ptep rcu_dereference > + > +#endif /* defined(__KVM_NVHE_HYPERVISOR__) */ > + > static inline kvm_pte_t kvm_pte_read(kvm_pte_t *ptep) > { > - return READ_ONCE(*ptep); > + kvm_pte_t __rcu *p = (kvm_pte_t __rcu *)ptep; > + > + return READ_ONCE(*kvm_dereference_ptep(p)); What about all the other places where page table memory is accessed? If RCU is going to be used to protect page table memory, then all accesses have to go under an RCU critical section. This means that page table memory should only be accessed through __rcu annotated pointers and dereferenced with rcu_dereference(). > } > > #endif /* __ARM64_KVM_PGTABLE_H__ */ > diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c > index f911509e6512..215a14c434ed 100644 > --- a/arch/arm64/kvm/hyp/pgtable.c > +++ b/arch/arm64/kvm/hyp/pgtable.c > @@ -284,8 +284,13 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, > .end = PAGE_ALIGN(walk_data.addr + size), > .walker = walker, > }; > + int r; > > - return _kvm_pgtable_walk(&walk_data); > + kvm_pgtable_walk_begin(); > + r = _kvm_pgtable_walk(&walk_data); > + kvm_pgtable_walk_end(); > + > + return r; > } > > struct leaf_walk_data { > -- > 2.37.2.672.g94769d06f0-goog > _______________________________________________ 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 E5C50C38145 for ; Wed, 7 Sep 2022 21:47:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230320AbiIGVrT (ORCPT ); Wed, 7 Sep 2022 17:47:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36364 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230313AbiIGVrR (ORCPT ); Wed, 7 Sep 2022 17:47:17 -0400 Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 68516BADA9 for ; Wed, 7 Sep 2022 14:47:16 -0700 (PDT) Received: by mail-pj1-x1033.google.com with SMTP id pj10so5395483pjb.2 for ; Wed, 07 Sep 2022 14:47:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date; bh=a0onBmXPphYT3RuqfDE1tfHpBM48udC3uDDfIPbNeqQ=; b=qz8qKS17YDB74dB3eVq/ImHb/1panXWt9MKNv77sjzlXj8cL3XwLCX/xz8ZQn9FJSc pkuvn/eM3SPKQUCBDgtCZu6rnvnlsgeB696oCeiPN8LzQIFq4odPuYBB/o7hizZaRcRP tH7JasNxHZyEVsUyfz0V/dL1r9OPMoCaBwGTkGjH1jd/RD5/uG56v/Pc1g6Dr4EGnH6r hr+0E5wBEw/x3ik8lSEvklHAQ6eORvUgxri4N5u/Sr7xvTrdNUpSsXg71MROLD6JhtYd nyD3JCmVLfqxQWXd75Tk6Z+u4KPOxj45s6/oI+dRFkvHvvGKtM9qmtSw3qCoO59EWNNk GKXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date; bh=a0onBmXPphYT3RuqfDE1tfHpBM48udC3uDDfIPbNeqQ=; b=Xhjx8etBWvkvVxv/yP9qZMe44zD+PuR7lv/5dU/c/oer0mbq8CwxT0Df/Zu+SxHrb/ 9DO264FQr2pypU0CC6q7jExhOM3U00mCllNQK4iMUH1EXmma/iFN+krOrQkJZ5I2Dp3w moc8BbAc+lEt/SCPGtxz2l+nUf0amdF9CKLyMZR4oQs3P1cebAOGWDhzNexX/MprFnwM gNusb8/qNDktTDTOWp1OSzTjNQSgHWndE6PRQAAS8vt6Auj+wbPfW1Zxb/eZuqY3+PD8 gE+7kCuWc6ZGACHk3ydMFv4qAsiN65EtUbrj3V7KVyIKX/d9brgmc5YNlFXxOKxNxA1u PdNA== X-Gm-Message-State: ACgBeo1fCgr2SWsM95VbEzGKnKXXJkcyrb1LPTfDgeDi/I2tNV89eKo9 DFLK3j67pF2HOdAyY5TMIyrlSw== X-Google-Smtp-Source: AA6agR7u55ulppnpFE92xnBEjpQea4OXXBFThe+B3Pt6YcvMkX+Mwtq2DlhDFlWJGj73EGApy3OVsw== X-Received: by 2002:a17:902:6b4c:b0:171:38ab:e762 with SMTP id g12-20020a1709026b4c00b0017138abe762mr5635735plt.42.1662587235722; Wed, 07 Sep 2022 14:47:15 -0700 (PDT) Received: from google.com (223.103.125.34.bc.googleusercontent.com. [34.125.103.223]) by smtp.gmail.com with ESMTPSA id n6-20020a170902e54600b00173cfaed233sm659052plf.62.2022.09.07.14.47.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Sep 2022 14:47:14 -0700 (PDT) Date: Wed, 7 Sep 2022 14:47:08 -0700 From: David Matlack To: Oliver Upton Cc: Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , Catalin Marinas , Will Deacon , Quentin Perret , Ricardo Koller , Reiji Watanabe , Ben Gardon , Paolo Bonzini , Gavin Shan , Peter Xu , Sean Christopherson , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 08/14] KVM: arm64: Protect page table traversal with RCU Message-ID: References: <20220830194132.962932-1-oliver.upton@linux.dev> <20220830194132.962932-9-oliver.upton@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220830194132.962932-9-oliver.upton@linux.dev> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Aug 30, 2022 at 07:41:26PM +0000, Oliver Upton wrote: > The use of RCU is necessary to change the paging structures in parallel. > Acquire and release an RCU read lock when traversing the page tables. > > Signed-off-by: Oliver Upton > --- > arch/arm64/include/asm/kvm_pgtable.h | 19 ++++++++++++++++++- > arch/arm64/kvm/hyp/pgtable.c | 7 ++++++- > 2 files changed, 24 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h > index 78fbb7be1af6..7d2de0a98ccb 100644 > --- a/arch/arm64/include/asm/kvm_pgtable.h > +++ b/arch/arm64/include/asm/kvm_pgtable.h > @@ -578,9 +578,26 @@ enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte); > */ > enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte); > > +#if defined(__KVM_NVHE_HYPERVISOR___) > + Future readers will wonder why NVHE stubs out RCU support and how that is even correct. Some comments here would be useful explain it. > +static inline void kvm_pgtable_walk_begin(void) {} > +static inline void kvm_pgtable_walk_end(void) {} > + > +#define kvm_dereference_ptep rcu_dereference_raw How does NVHE have access rcu_dereference_raw()? > + > +#else /* !defined(__KVM_NVHE_HYPERVISOR__) */ > + > +#define kvm_pgtable_walk_begin rcu_read_lock > +#define kvm_pgtable_walk_end rcu_read_unlock > +#define kvm_dereference_ptep rcu_dereference > + > +#endif /* defined(__KVM_NVHE_HYPERVISOR__) */ > + > static inline kvm_pte_t kvm_pte_read(kvm_pte_t *ptep) > { > - return READ_ONCE(*ptep); > + kvm_pte_t __rcu *p = (kvm_pte_t __rcu *)ptep; > + > + return READ_ONCE(*kvm_dereference_ptep(p)); What about all the other places where page table memory is accessed? If RCU is going to be used to protect page table memory, then all accesses have to go under an RCU critical section. This means that page table memory should only be accessed through __rcu annotated pointers and dereferenced with rcu_dereference(). > } > > #endif /* __ARM64_KVM_PGTABLE_H__ */ > diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c > index f911509e6512..215a14c434ed 100644 > --- a/arch/arm64/kvm/hyp/pgtable.c > +++ b/arch/arm64/kvm/hyp/pgtable.c > @@ -284,8 +284,13 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, > .end = PAGE_ALIGN(walk_data.addr + size), > .walker = walker, > }; > + int r; > > - return _kvm_pgtable_walk(&walk_data); > + kvm_pgtable_walk_begin(); > + r = _kvm_pgtable_walk(&walk_data); > + kvm_pgtable_walk_end(); > + > + return r; > } > > struct leaf_walk_data { > -- > 2.37.2.672.g94769d06f0-goog >