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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5BFB3C433EF for ; Tue, 3 May 2022 01:13:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 881706B0071; Mon, 2 May 2022 21:13:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 83A716B0073; Mon, 2 May 2022 21:13:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6CEE26B0074; Mon, 2 May 2022 21:13:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id 5DD6D6B0071 for ; Mon, 2 May 2022 21:13:26 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 2D5BA2199C for ; Tue, 3 May 2022 01:13:26 +0000 (UTC) X-FDA: 79422658812.26.251A1B2 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf16.hostedemail.com (Postfix) with ESMTP id 8250C180088 for ; Tue, 3 May 2022 01:13:19 +0000 (UTC) Received: from kwepemi500004.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Kshly6yS3zhYnw; Tue, 3 May 2022 09:13:02 +0800 (CST) Received: from kwepemm600017.china.huawei.com (7.193.23.234) by kwepemi500004.china.huawei.com (7.221.188.17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 3 May 2022 09:13:22 +0800 Received: from [10.174.179.234] (10.174.179.234) by kwepemm600017.china.huawei.com (7.193.23.234) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 3 May 2022 09:13:21 +0800 Message-ID: <80f6c347-db5d-8836-bc79-60c7b2a6eed8@huawei.com> Date: Tue, 3 May 2022 09:13:20 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH -next v6 5/6] arm64/mm: Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK To: Anshuman Khandual , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , , "H. Peter Anvin" , Pasha Tatashin , Andrew Morton , Catalin Marinas , Will Deacon , Paul Walmsley , Palmer Dabbelt , Albert Ou CC: , , , , Kefeng Wang , Guohanjun References: <20220426081036.1374452-1-tongtiangen@huawei.com> <20220426081036.1374452-6-tongtiangen@huawei.com> From: Tong Tiangen In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.179.234] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemm600017.china.huawei.com (7.193.23.234) X-CFilter-Loop: Reflected X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 8250C180088 X-Stat-Signature: gag9wfoqps6jjot7z3u5zj3rd7agw4au Authentication-Results: imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of tongtiangen@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=tongtiangen@huawei.com X-Rspam-User: X-HE-Tag: 1651540399-873167 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 在 2022/4/29 14:18, Anshuman Khandual 写道: > > > On 4/26/22 13:40, Tong Tiangen wrote: >> From: Kefeng Wang >> >> As commit d283d422c6c4 ("x86: mm: add x86_64 support for page table check") >> , enable ARCH_SUPPORTS_PAGE_TABLE_CHECK on arm64. >> >> Add additional page table check stubs for page table helpers, these stubs >> can be used to check the existing page table entries. >> >> Signed-off-by: Kefeng Wang >> Signed-off-by: Tong Tiangen >> Reviewed-by: Pasha Tatashin >> --- >> arch/arm64/Kconfig | 1 + >> arch/arm64/include/asm/pgtable.h | 59 +++++++++++++++++++++++++++++--- >> 2 files changed, 55 insertions(+), 5 deletions(-) >> >> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig >> index 18a18a0e855d..c1509525ab8e 100644 >> --- a/arch/arm64/Kconfig >> +++ b/arch/arm64/Kconfig >> @@ -92,6 +92,7 @@ config ARM64 >> select ARCH_SUPPORTS_ATOMIC_RMW >> select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 >> select ARCH_SUPPORTS_NUMA_BALANCING >> + select ARCH_SUPPORTS_PAGE_TABLE_CHECK >> select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT >> select ARCH_WANT_DEFAULT_BPF_JIT >> select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT >> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h >> index ad9b221963d4..fe17788a6885 100644 >> --- a/arch/arm64/include/asm/pgtable.h >> +++ b/arch/arm64/include/asm/pgtable.h >> @@ -33,6 +33,7 @@ >> #include >> #include >> #include >> +#include >> >> #ifdef CONFIG_TRANSPARENT_HUGEPAGE >> #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE >> @@ -96,6 +97,7 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) >> #define pte_young(pte) (!!(pte_val(pte) & PTE_AF)) >> #define pte_special(pte) (!!(pte_val(pte) & PTE_SPECIAL)) >> #define pte_write(pte) (!!(pte_val(pte) & PTE_WRITE)) >> +#define pte_user(pte) (!!(pte_val(pte) & PTE_USER)) >> #define pte_user_exec(pte) (!(pte_val(pte) & PTE_UXN)) >> #define pte_cont(pte) (!!(pte_val(pte) & PTE_CONT)) >> #define pte_devmap(pte) (!!(pte_val(pte) & PTE_DEVMAP)) >> @@ -312,7 +314,7 @@ static inline void __check_racy_pte_update(struct mm_struct *mm, pte_t *ptep, >> __func__, pte_val(old_pte), pte_val(pte)); >> } >> >> -static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, >> +static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, >> pte_t *ptep, pte_t pte) > > A small nit. Subsequent line containing the arguments "pte_t *ptep ..." > needs to be aligned properly, after '__' got added into set_pte_at(). OK, missing that, .will fix it next version. > >> { >> if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte)) >> @@ -343,6 +345,13 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, >> set_pte(ptep, pte); >> } >> >> +static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, >> + pte_t *ptep, pte_t pte) >> +{ >> + page_table_check_pte_set(mm, addr, ptep, pte); >> + return __set_pte_at(mm, addr, ptep, pte); >> +} >> + >> /* >> * Huge pte definitions. >> */ >> @@ -454,6 +463,8 @@ static inline int pmd_trans_huge(pmd_t pmd) >> #define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd)) >> #define pmd_young(pmd) pte_young(pmd_pte(pmd)) >> #define pmd_valid(pmd) pte_valid(pmd_pte(pmd)) >> +#define pmd_user(pmd) pte_user(pmd_pte(pmd)) >> +#define pmd_user_exec(pmd) pte_user_exec(pmd_pte(pmd)) >> #define pmd_cont(pmd) pte_cont(pmd_pte(pmd)) >> #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd))) >> #define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd))) >> @@ -501,8 +512,19 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd) >> #define pud_pfn(pud) ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT) >> #define pfn_pud(pfn,prot) __pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) >> >> -#define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd)) >> -#define set_pud_at(mm, addr, pudp, pud) set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud)) >> +static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, >> + pmd_t *pmdp, pmd_t pmd) >> +{ >> + page_table_check_pmd_set(mm, addr, pmdp, pmd); >> + return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd)); >> +} >> + >> +static inline void set_pud_at(struct mm_struct *mm, unsigned long addr, >> + pud_t *pudp, pud_t pud) >> +{ >> + page_table_check_pud_set(mm, addr, pudp, pud); >> + return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud)); >> +} >> >> #define __p4d_to_phys(p4d) __pte_to_phys(p4d_pte(p4d)) >> #define __phys_to_p4d_val(phys) __phys_to_pte_val(phys) >> @@ -643,6 +665,24 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd) >> #define pud_present(pud) pte_present(pud_pte(pud)) >> #define pud_leaf(pud) pud_sect(pud) >> #define pud_valid(pud) pte_valid(pud_pte(pud)) >> +#define pud_user(pud) pte_user(pud_pte(pud)) >> + >> +#ifdef CONFIG_PAGE_TABLE_CHECK >> +static inline bool pte_user_accessible_page(pte_t pte) >> +{ >> + return pte_present(pte) && (pte_user(pte) || pte_user_exec(pte)); >> +} >> + >> +static inline bool pmd_user_accessible_page(pmd_t pmd) >> +{ >> + return pmd_present(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd)); >> +} >> + >> +static inline bool pud_user_accessible_page(pud_t pud) >> +{ >> + return pud_present(pud) && pud_user(pud); >> +} >> +#endif >> >> static inline void set_pud(pud_t *pudp, pud_t pud) >> { >> @@ -876,7 +916,11 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, >> static inline pte_t ptep_get_and_clear(struct mm_struct *mm, >> unsigned long address, pte_t *ptep) >> { >> - return __pte(xchg_relaxed(&pte_val(*ptep), 0)); >> + pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0)); >> + >> + page_table_check_pte_clear(mm, address, pte); >> + >> + return pte; >> } >> >> #ifdef CONFIG_TRANSPARENT_HUGEPAGE >> @@ -884,7 +928,11 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, >> static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, >> unsigned long address, pmd_t *pmdp) >> { >> - return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp)); >> + pmd_t pmd = pte_pmd(__pte(xchg_relaxed(&pte_val(*(pte_t *)pmdp), 0))); > > Why there is any change here ? Why not just the following instead, like what you did > in ptep_get_and_clear() above. The page table entry return value here just needs to > be preserved for subsequent page table check helpers. > > pmd_t pmd = pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp)); > Hi Anshuman: The purpose of what I do here is to avoid doing page_table_check_pte_clear() in ptep_get_and_clear(). there is no functional change here. Thanks, Tong. >> + >> + page_table_check_pmd_clear(mm, address, pmd); >> + >> + return pmd; >> } >> #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ >> >> @@ -918,6 +966,7 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm, >> static inline pmd_t pmdp_establish(struct vm_area_struct *vma, >> unsigned long address, pmd_t *pmdp, pmd_t pmd) >> { >> + page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd); >> return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd))); >> } >> #endif > .