From patchwork Thu Apr 30 09:24:42 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Slaby X-Patchwork-Id: 47787 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-wg0-f72.google.com (mail-wg0-f72.google.com [74.125.82.72]) by ip-10-151-82-157.ec2.internal (Postfix) with ESMTPS id 28B0F20553 for ; Thu, 30 Apr 2015 09:26:23 +0000 (UTC) Received: by wgiv13 with SMTP id v13sf13174864wgi.3 for ; Thu, 30 Apr 2015 02:26:22 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:delivered-to:from:to:cc:subject :date:message-id:in-reply-to:references:sender:precedence:list-id :x-original-sender:x-original-authentication-results:mailing-list :list-post:list-help:list-archive:list-unsubscribe; bh=UI/LNVq2E6HPE4Aqfu6+Haxmukzy3xXxrbZttE3/Gew=; b=F0AlIyFIquleexa6q7kSpO3cHsnnwATm/CrShltzetkfEaCfJAtUIUzWHKkB9honbN pyzx32Yr48cyfgtz61OxWPVx2WselcAzNFKfSjAMOeBUV78ml1C2KZL3P0ragskhGlVE XqENNP644fRc8IgOaowdpFa0zkhxtE2x/m1MENf2iKCMGxh/FaKJIZ6VFHsChu91RK8X husRXZELinPw+re90N70xod0bk1MAYU1RoSztkBTt2ncYo2lC0TtW8V+06oq3k76zNoS SFuSPVh6LVvtPkVAz1ikHrRA3a3s0yojRaTB4mLop6MfaaMuH5NRwDScos+c9BPSdVEd kQDg== X-Gm-Message-State: ALoCoQmo171hvE7Tac0Di0FozkBIXBMgaIVCnr60DZHd3svcXUf4TP83ZLcZLBIFkdcg7N8Gdg8Y X-Received: by 10.180.85.129 with SMTP id h1mr1210098wiz.6.1430385982499; Thu, 30 Apr 2015 02:26:22 -0700 (PDT) MIME-Version: 1.0 X-BeenThere: patchwork-forward@linaro.org Received: by 10.152.37.40 with SMTP id v8ls316662laj.88.gmail; Thu, 30 Apr 2015 02:26:22 -0700 (PDT) X-Received: by 10.112.142.232 with SMTP id rz8mr2905800lbb.74.1430385982284; Thu, 30 Apr 2015 02:26:22 -0700 (PDT) Received: from mail-lb0-f178.google.com (mail-lb0-f178.google.com. [209.85.217.178]) by mx.google.com with ESMTPS id q6si1331833lby.85.2015.04.30.02.26.22 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 30 Apr 2015 02:26:22 -0700 (PDT) Received-SPF: pass (google.com: domain of patch+caf_=patchwork-forward=linaro.org@linaro.org designates 209.85.217.178 as permitted sender) client-ip=209.85.217.178; Received: by lbbzk7 with SMTP id zk7so39929916lbb.0 for ; Thu, 30 Apr 2015 02:26:22 -0700 (PDT) X-Received: by 10.113.10.134 with SMTP id ea6mr2938249lbd.29.1430385982202; Thu, 30 Apr 2015 02:26:22 -0700 (PDT) X-Forwarded-To: patchwork-forward@linaro.org X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org Delivered-To: patch@linaro.org Received: by 10.112.67.65 with SMTP id l1csp2995692lbt; Thu, 30 Apr 2015 02:26:21 -0700 (PDT) X-Received: by 10.70.56.98 with SMTP id z2mr6442772pdp.120.1430385952009; Thu, 30 Apr 2015 02:25:52 -0700 (PDT) Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id nf2si2640288pbc.149.2015.04.30.02.25.51; Thu, 30 Apr 2015 02:25:52 -0700 (PDT) Received-SPF: none (google.com: stable-owner@vger.kernel.org does not designate permitted sender hosts) client-ip=209.132.180.67; Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750947AbbD3JZl (ORCPT + 2 others); Thu, 30 Apr 2015 05:25:41 -0400 Received: from ip4-83-240-67-251.cust.nbox.cz ([83.240.67.251]:52966 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751114AbbD3JZO (ORCPT ); Thu, 30 Apr 2015 05:25:14 -0400 Received: from ku by ip4-83-240-18-248.cust.nbox.cz with local (Exim 4.85) (envelope-from ) id 1YnkiW-0005O5-7E; Thu, 30 Apr 2015 11:25:12 +0200 From: Jiri Slaby To: stable@vger.kernel.org Cc: Christoffer Dall , Shannon Zhao , Jiri Slaby Subject: [patch added to the 3.12 stable tree] arm/arm64: KVM: Fix and refactor unmap_range Date: Thu, 30 Apr 2015 11:24:42 +0200 Message-Id: <1430385911-20480-34-git-send-email-jslaby@suse.cz> X-Mailer: git-send-email 2.3.5 In-Reply-To: <1430385911-20480-1-git-send-email-jslaby@suse.cz> References: <1430385911-20480-1-git-send-email-jslaby@suse.cz> Sender: stable-owner@vger.kernel.org Precedence: list List-ID: X-Mailing-List: stable@vger.kernel.org X-Removed-Original-Auth: Dkim didn't pass. X-Original-Sender: patch@linaro.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of patch+caf_=patchwork-forward=linaro.org@linaro.org designates 209.85.217.178 as permitted sender) smtp.mail=patch+caf_=patchwork-forward=linaro.org@linaro.org Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org X-Google-Group-Id: 836684582541 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , From: Christoffer Dall This patch has been added to the 3.12 stable tree. If you have any objections, please let us know. =============== commit 4f853a714bf16338ff5261128e6c7ae2569e9505 upstream. unmap_range() was utterly broken, to quote Marc, and broke in all sorts of situations. It was also quite complicated to follow and didn't follow the usual scheme of having a separate iterating function for each level of page tables. Address this by refactoring the code and introduce a pgd_clear() function. Reviewed-by: Jungseok Lee Reviewed-by: Mario Smarduch Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall Signed-off-by: Shannon Zhao Signed-off-by: Jiri Slaby --- arch/arm/include/asm/kvm_mmu.h | 11 ++++ arch/arm/kvm/mmu.c | 106 +++++++++++++++++++++++---------------- arch/arm64/include/asm/kvm_mmu.h | 14 ++++++ 3 files changed, 89 insertions(+), 42 deletions(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 1de3a9b7bab6..a2c3c313ea77 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -116,6 +116,17 @@ static inline void kvm_set_s2pte_writable(pte_t *pte) (__boundary - 1 < (end) - 1)? __boundary: (end); \ }) +static inline bool kvm_page_empty(void *ptr) +{ + struct page *ptr_page = virt_to_page(ptr); + return page_count(ptr_page) == 1; +} + + +#define kvm_pte_table_empty(ptep) kvm_page_empty(ptep) +#define kvm_pmd_table_empty(pmdp) kvm_page_empty(pmdp) +#define kvm_pud_table_empty(pudp) (0) + struct kvm; #define kvm_flush_dcache_to_poc(a,l) __cpuc_flush_dcache_area((a), (l)) diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 61c5a92f6d9d..8e364f793c2c 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -87,10 +87,13 @@ static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc) return p; } -static bool page_empty(void *ptr) +static void clear_pgd_entry(struct kvm *kvm, pgd_t *pgd, phys_addr_t addr) { - struct page *ptr_page = virt_to_page(ptr); - return page_count(ptr_page) == 1; + pud_t *pud_table __maybe_unused = pud_offset(pgd, 0); + pgd_clear(pgd); + kvm_tlb_flush_vmid_ipa(kvm, addr); + pud_free(NULL, pud_table); + put_page(virt_to_page(pgd)); } static void clear_pud_entry(struct kvm *kvm, pud_t *pud, phys_addr_t addr) @@ -111,55 +114,74 @@ static void clear_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr) put_page(virt_to_page(pmd)); } -static void clear_pte_entry(struct kvm *kvm, pte_t *pte, phys_addr_t addr) +static void unmap_ptes(struct kvm *kvm, pmd_t *pmd, + phys_addr_t addr, phys_addr_t end) { - if (pte_present(*pte)) { - kvm_set_pte(pte, __pte(0)); - put_page(virt_to_page(pte)); - kvm_tlb_flush_vmid_ipa(kvm, addr); - } + phys_addr_t start_addr = addr; + pte_t *pte, *start_pte; + + start_pte = pte = pte_offset_kernel(pmd, addr); + do { + if (!pte_none(*pte)) { + kvm_set_pte(pte, __pte(0)); + put_page(virt_to_page(pte)); + kvm_tlb_flush_vmid_ipa(kvm, addr); + } + } while (pte++, addr += PAGE_SIZE, addr != end); + + if (kvm_pte_table_empty(start_pte)) + clear_pmd_entry(kvm, pmd, start_addr); } -static void unmap_range(struct kvm *kvm, pgd_t *pgdp, - unsigned long long start, u64 size) +static void unmap_pmds(struct kvm *kvm, pud_t *pud, + phys_addr_t addr, phys_addr_t end) { - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - unsigned long long addr = start, end = start + size; - u64 next; + phys_addr_t next, start_addr = addr; + pmd_t *pmd, *start_pmd; - while (addr < end) { - pgd = pgdp + pgd_index(addr); - pud = pud_offset(pgd, addr); - if (pud_none(*pud)) { - addr = kvm_pud_addr_end(addr, end); - continue; + start_pmd = pmd = pmd_offset(pud, addr); + do { + next = kvm_pmd_addr_end(addr, end); + if (!pmd_none(*pmd)) { + unmap_ptes(kvm, pmd, addr, next); } + } while (pmd++, addr = next, addr != end); - pmd = pmd_offset(pud, addr); - if (pmd_none(*pmd)) { - addr = kvm_pmd_addr_end(addr, end); - continue; - } + if (kvm_pmd_table_empty(start_pmd)) + clear_pud_entry(kvm, pud, start_addr); +} - pte = pte_offset_kernel(pmd, addr); - clear_pte_entry(kvm, pte, addr); - next = addr + PAGE_SIZE; - - /* If we emptied the pte, walk back up the ladder */ - if (page_empty(pte)) { - clear_pmd_entry(kvm, pmd, addr); - next = kvm_pmd_addr_end(addr, end); - if (page_empty(pmd) && !page_empty(pud)) { - clear_pud_entry(kvm, pud, addr); - next = kvm_pud_addr_end(addr, end); - } +static void unmap_puds(struct kvm *kvm, pgd_t *pgd, + phys_addr_t addr, phys_addr_t end) +{ + phys_addr_t next, start_addr = addr; + pud_t *pud, *start_pud; + + start_pud = pud = pud_offset(pgd, addr); + do { + next = kvm_pud_addr_end(addr, end); + if (!pud_none(*pud)) { + unmap_pmds(kvm, pud, addr, next); } + } while (pud++, addr = next, addr != end); - addr = next; - } + if (kvm_pud_table_empty(start_pud)) + clear_pgd_entry(kvm, pgd, start_addr); +} + + +static void unmap_range(struct kvm *kvm, pgd_t *pgdp, + phys_addr_t start, u64 size) +{ + pgd_t *pgd; + phys_addr_t addr = start, end = start + size; + phys_addr_t next; + + pgd = pgdp + pgd_index(addr); + do { + next = kvm_pgd_addr_end(addr, end); + unmap_puds(kvm, pgd, addr, next); + } while (pgd++, addr = next, addr != end); } static void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd, diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 3b038b39ba9b..db6b8f69e3f5 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -119,6 +119,20 @@ static inline void kvm_set_s2pte_writable(pte_t *pte) #define kvm_pud_addr_end(addr, end) pud_addr_end(addr, end) #define kvm_pmd_addr_end(addr, end) pmd_addr_end(addr, end) +static inline bool kvm_page_empty(void *ptr) +{ + struct page *ptr_page = virt_to_page(ptr); + return page_count(ptr_page) == 1; +} + +#define kvm_pte_table_empty(ptep) kvm_page_empty(ptep) +#ifndef CONFIG_ARM64_64K_PAGES +#define kvm_pmd_table_empty(pmdp) kvm_page_empty(pmdp) +#else +#define kvm_pmd_table_empty(pmdp) (0) +#endif +#define kvm_pud_table_empty(pudp) (0) + struct kvm; #define kvm_flush_dcache_to_poc(a,l) __flush_dcache_area((a), (l))