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 C7DB0C433F5 for ; Tue, 22 Feb 2022 03:12:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231777AbiBVDNR (ORCPT ); Mon, 21 Feb 2022 22:13:17 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:54306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233492AbiBVDNR (ORCPT ); Mon, 21 Feb 2022 22:13:17 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9A0415FA8 for ; Mon, 21 Feb 2022 19:12:52 -0800 (PST) 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 3E9C261521 for ; Tue, 22 Feb 2022 03:12:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F042C340E9; Tue, 22 Feb 2022 03:12:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1645499571; bh=kgCvLVSNKHqYW2DtyMqMirLoSoKFEG+BiTSGvnHwAvE=; h=Date:To:From:Subject:From; b=AWsff6XDedKXeUIO2DsUdtWDTjd3mKx2y7UZTh6/OtD8zwhgRbc0ypkF9AWj9IX3u 5oiE3aC0yyhqFfyQnuLf+s/mWkHAJvsWHhejlANhSqMZ7pjCHoaJTFHRktm0EsEJM2 SxZD8b/JFryq9y48sjk6tl7McW0SszcIqZgmAoSk= Date: Mon, 21 Feb 2022 19:12:50 -0800 To: mm-commits@vger.kernel.org, ysato@users.sourceforge.jp, will@kernel.org, vgupta@kernel.org, tsbogend@alpha.franken.de, tglx@linutronix.de, svens@linux.ibm.com, shorne@gmail.com, rth@twiddle.net, paul.walmsley@sifive.com, paulus@samba.org, palmer@dabbelt.com, nickhu@andestech.com, mpe@ellerman.id.au, monstr@monstr.eu, mingo@redhat.com, linux@armlinux.org.uk, khalid.aziz@oracle.com, jonas@southpole.se, jdike@addtoit.com, James.Bottomley@HansenPartnership.com, hch@lst.de, hca@linux.ibm.com, guoren@kernel.org, gor@linux.ibm.com, geert@linux-m68k.org, dinguyen@kernel.org, davem@davemloft.net, dalias@libc.org, chris@zankel.net, catalin.marinas@arm.com, bcain@codeaurora.org, arnd@arndb.de, anshuman.khandual@arm.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-debug_vm_pgtable-drop-protection_map-usage.patch added to -mm tree Message-Id: <20220222031251.7F042C340E9@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/debug_vm_pgtable: drop protection_map[] usage has been added to the -mm tree. Its filename is mm-debug_vm_pgtable-drop-protection_map-usage.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-debug_vm_pgtable-drop-protection_map-usage.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-debug_vm_pgtable-drop-protection_map-usage.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Anshuman Khandual Subject: mm/debug_vm_pgtable: drop protection_map[] usage Patch series "mm/mmap: Drop protection_map[] and platform's __SXXX/__PXXX requirements", v2. protection_map[] is an array based construct that translates given vm_flags combination. This array contains page protection map, which is populated by the platform via [__S000 .. __S111] and [__P000 .. __P111] exported macros. Primary usage for protection_map[] is for vm_get_page_prot(), which is used to determine page protection value for a given vm_flags. vm_get_page_prot() implementation, could again call platform overrides arch_vm_get_page_prot() and arch_filter_pgprot(). Some platforms override protection_map[] that was originally built with __SXXX/__PXXX with different runtime values. Currently there are multiple layers of abstraction i.e __SXXX/__PXXX macros , protection_map[], arch_vm_get_page_prot() and arch_filter_pgprot() built between the platform and generic MM, finally defining vm_get_page_prot(). Hence this series proposes to drop all these abstraction levels and instead just move the responsibility of defining vm_get_page_prot() to the platform itself making it clean and simple. This first introduces ARCH_HAS_VM_GET_PAGE_PROT which enables the platforms to define custom vm_get_page_prot(). This starts converting platforms that either change protection_map[] or define the overrides arch_filter_pgprot() or arch_vm_get_page_prot() which enables for those constructs to be dropped off completely. This series then converts remaining platforms which enables for __SXXX/__PXXX constructs to be dropped off completely. Finally it drops the generic vm_get_page_prot() and then ARCH_HAS_VM_GET_PAGE_PROT as every platform now defines their own vm_get_page_prot(). The series has been inspired from an earlier discuss with Christoph Hellwig https://lore.kernel.org/all/1632712920-8171-1-git-send-email-anshuman.khandual@arm.com/ This series has been cross built for multiple platforms. This patch (of 30): Although protection_map[] contains the platform defined page protection map for a given vm_flags combination, vm_get_page_prot() is the right interface to use. This will also reduce dependency on protection_map[] which is going to be dropped off completely later on. Link: https://lkml.kernel.org/r/1645425519-9034-1-git-send-email-anshuman.khandual@arm.com Link: https://lkml.kernel.org/r/1645425519-9034-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Cc: Arnd Bergmann Cc: Brian Cain Cc: Catalin Marinas Cc: Christoph Hellwig Cc: Chris Zankel Cc: David S. Miller Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Heiko Carstens Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Jeff Dike Cc: Jonas Bonn Cc: Khalid Aziz Cc: Michael Ellerman Cc: Michal Simek Cc: Nick Hu Cc: Palmer Dabbelt Cc: Paul Mackerras Cc: Paul Walmsley Cc: Richard Henderson Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Sven Schnelle Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Signed-off-by: Andrew Morton --- mm/debug_vm_pgtable.c | 31 +++++++++++++++++++------------ 1 file changed, 19 insertions(+), 12 deletions(-) --- a/mm/debug_vm_pgtable.c~mm-debug_vm_pgtable-drop-protection_map-usage +++ a/mm/debug_vm_pgtable.c @@ -93,7 +93,7 @@ struct pgtable_debug_args { static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx) { - pgprot_t prot = protection_map[idx]; + pgprot_t prot = vm_get_page_prot(idx); pte_t pte = pfn_pte(args->fixed_pte_pfn, prot); unsigned long val = idx, *ptr = &val; @@ -101,7 +101,7 @@ static void __init pte_basic_tests(struc /* * This test needs to be executed after the given page table entry - * is created with pfn_pte() to make sure that protection_map[idx] + * is created with pfn_pte() to make sure that vm_get_page_prot(idx) * does not have the dirty bit enabled from the beginning. This is * important for platforms like arm64 where (!PTE_RDONLY) indicate * dirty bit being set. @@ -190,7 +190,7 @@ static void __init pte_savedwrite_tests( #ifdef CONFIG_TRANSPARENT_HUGEPAGE static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx) { - pgprot_t prot = protection_map[idx]; + pgprot_t prot = vm_get_page_prot(idx); unsigned long val = idx, *ptr = &val; pmd_t pmd; @@ -202,7 +202,7 @@ static void __init pmd_basic_tests(struc /* * This test needs to be executed after the given page table entry - * is created with pfn_pmd() to make sure that protection_map[idx] + * is created with pfn_pmd() to make sure that vm_get_page_prot(idx) * does not have the dirty bit enabled from the beginning. This is * important for platforms like arm64 where (!PTE_RDONLY) indicate * dirty bit being set. @@ -325,7 +325,7 @@ static void __init pmd_savedwrite_tests( #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) { - pgprot_t prot = protection_map[idx]; + pgprot_t prot = vm_get_page_prot(idx); unsigned long val = idx, *ptr = &val; pud_t pud; @@ -337,7 +337,7 @@ static void __init pud_basic_tests(struc /* * This test needs to be executed after the given page table entry - * is created with pfn_pud() to make sure that protection_map[idx] + * is created with pfn_pud() to make sure that vm_get_page_prot(idx) * does not have the dirty bit enabled from the beginning. This is * important for platforms like arm64 where (!PTE_RDONLY) indicate * dirty bit being set. @@ -1106,14 +1106,14 @@ static int __init init_args(struct pgtab /* * Initialize the debugging data. * - * protection_map[0] (or even protection_map[8]) will help create - * page table entries with PROT_NONE permission as required for - * pxx_protnone_tests(). + * vm_get_page_prot(VM_NONE) or vm_get_page_prot(VM_SHARED|VM_NONE) + * will help create page table entries with PROT_NONE permission as + * required for pxx_protnone_tests(). */ memset(args, 0, sizeof(*args)); args->vaddr = get_random_vaddr(); args->page_prot = vm_get_page_prot(VMFLAGS); - args->page_prot_none = protection_map[0]; + args->page_prot_none = vm_get_page_prot(VM_NONE); args->is_contiguous_page = false; args->pud_pfn = ULONG_MAX; args->pmd_pfn = ULONG_MAX; @@ -1248,12 +1248,19 @@ static int __init debug_vm_pgtable(void) return ret; /* - * Iterate over the protection_map[] to make sure that all + * Iterate over each possible vm_flags to make sure that all * the basic page table transformation validations just hold * true irrespective of the starting protection value for a * given page table entry. + * + * Protection based vm_flags combinatins are always linear + * and increasing i.e starting from VM_NONE and going upto + * (VM_SHARED | READ | WRITE | EXEC). */ - for (idx = 0; idx < ARRAY_SIZE(protection_map); idx++) { +#define VM_FLAGS_START (VM_NONE) +#define VM_FLAGS_END (VM_SHARED | VM_EXEC | VM_WRITE | VM_READ) + + for (idx = VM_FLAGS_START; idx <= VM_FLAGS_END; idx++) { pte_basic_tests(&args, idx); pmd_basic_tests(&args, idx); pud_basic_tests(&args, idx); _ Patches currently in -mm which might be from anshuman.khandual@arm.com are mm-generalize-arch_has_filter_pgprot.patch mm-merge-pte_mkhuge-call-into-arch_make_huge_pte.patch mm-debug_vm_pgtable-drop-protection_map-usage.patch mm-mmap-clarify-protection_map-indices.patch mm-mmap-add-new-config-arch_has_vm_get_page_prot.patch powerpc-mm-enable-arch_has_vm_get_page_prot.patch arm64-mm-enable-arch_has_vm_get_page_prot.patch sparc-mm-enable-arch_has_vm_get_page_prot.patch mips-mm-enable-arch_has_vm_get_page_prot.patch m68k-mm-enable-arch_has_vm_get_page_prot.patch arm-mm-enable-arch_has_vm_get_page_prot.patch mm-mmap-drop-protection_map.patch mm-mmap-drop-arch_filter_pgprot.patch mm-mmap-drop-arch_vm_get_page_pgprot.patch s390-mm-enable-arch_has_vm_get_page_prot.patch riscv-mm-enable-arch_has_vm_get_page_prot.patch alpha-mm-enable-arch_has_vm_get_page_prot.patch sh-mm-enable-arch_has_vm_get_page_prot.patch arc-mm-enable-arch_has_vm_get_page_prot.patch csky-mm-enable-arch_has_vm_get_page_prot.patch extensa-mm-enable-arch_has_vm_get_page_prot.patch parisc-mm-enable-arch_has_vm_get_page_prot.patch openrisc-mm-enable-arch_has_vm_get_page_prot.patch um-mm-enable-arch_has_vm_get_page_prot.patch microblaze-mm-enable-arch_has_vm_get_page_prot.patch nios2-mm-enable-arch_has_vm_get_page_prot.patch hexagon-mm-enable-arch_has_vm_get_page_prot.patch nds32-mm-enable-arch_has_vm_get_page_prot.patch ia64-mm-enable-arch_has_vm_get_page_prot.patch mm-mmap-drop-generic-vm_get_page_prot.patch mm-mmap-drop-arch_has_vm_get_page_prot.patch mm-hugetlb-generalize-arch_want_general_hugetlb.patch mm-migration-add-trace-events-for-thp-migrations.patch mm-migration-add-trace-events-for-base-page-and-hugetlb-migrations.patch