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 X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,PDS_BTC_ID,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E08EDC43603 for ; Fri, 6 Dec 2019 13:53:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD46E20706 for ; Fri, 6 Dec 2019 13:53:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726317AbfLFNxo (ORCPT ); Fri, 6 Dec 2019 08:53:44 -0500 Received: from foss.arm.com ([217.140.110.172]:44332 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726171AbfLFNxo (ORCPT ); Fri, 6 Dec 2019 08:53:44 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id F0A49DA7; Fri, 6 Dec 2019 05:53:42 -0800 (PST) Received: from e112269-lin.cambridge.arm.com (e112269-lin.cambridge.arm.com [10.1.194.43]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6DCDF3F718; Fri, 6 Dec 2019 05:53:40 -0800 (PST) From: Steven Price To: Andrew Morton , linux-mm@kvack.org Cc: Steven Price , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Dave Hansen , Ingo Molnar , James Morse , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Peter Zijlstra , Thomas Gleixner , Will Deacon , x86@kernel.org, "H. Peter Anvin" , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mark Rutland , "Liang, Kan" Subject: [PATCH v16 00/25] Generic page walk and ptdump Date: Fri, 6 Dec 2019 13:52:51 +0000 Message-Id: <20191206135316.47703-1-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since this series is still in linux-next and causing problems I'm sending this out before -rc1. This version adds two new patches over the previous series (v15): 13: mm: pagewalk: Don't lock PTEs for walk_page_range_novma() 14: mm: pagewalk: fix termination condition in walk_pte_range() Patch 13 solves the conflict with ace88f1018b8 ("mm: pagewalk: Take the pagetable lock in walk_pte_range()") by not taking the lock for the _novma() version of the function. Patch 14 fixes an existing issue with walk_pte_range() whereby if the end address isn't aligned to PAGE_SIZE the loop will be infinite. This starts to trigger on some x86 32 bit configurations with the generic ptdump support because there is a page in the last PMD which means that the end address is ~0UL. I've posted these patches separately as I think they do stand alone (and shouldn't cause bisection problems) - but 13/14 could potentially be squashed into 12. Patch 12 ("mm: pagewalk: Allow walking without vma") has also been updated from v15 to include the p*d_present() check that was posted[1] after v15 and Andrew squashed into the commit. Patch 21 ("mm: Add generic ptdump") also has the fix from Qian Cai squashed in to fix the order of "static const". [1] https://lore.kernel.org/lkml/16da6118-ac4d-a165-6202-0731a776ac72@arm.com/ Previous description for the series: Many architectures current have a debugfs file for dumping the kernel page tables. Currently each architecture has to implement custom functions for this because the details of walking the page tables used by the kernel are different between architectures. This series extends the capabilities of walk_page_range() so that it can deal with the page tables of the kernel (which have no VMAs and can contain larger huge pages than exist for user space). A generic PTDUMP implementation is the implemented making use of the new functionality of walk_page_range() and finally arm64 and x86 are switch to using it, removing the custom table walkers. To enable a generic page table walker to walk the unusual mappings of the kernel we need to implement a set of functions which let us know when the walker has reached the leaf entry. After a suggestion from Will Deacon I've chosen the name p?d_leaf() as this (hopefully) describes the purpose (and is a new name so has no historic baggage). Some architectures have p?d_large macros but this is easily confused with "large pages". This series ends with a generic PTDUMP implemention for arm64 and x86. Mostly this is a clean up and there should be very little functional change. The exceptions are: * arm64 PTDUMP debugfs now displays pages which aren't present (patch 22). * arm64 has the ability to efficiently process KASAN pages (which previously only x86 implemented). This means that the combination of KASAN and DEBUG_WX is now useable. Also available as a git tree: git://linux-arm.org/linux-sp.git walk_page_range/v16 Changes since v15: https://lore.kernel.org/lkml/20191101140942.51554-1-steven.price@arm.com/ * Rebased onto Linus' tree, which includes the conflicting commit: ace88f1018b8 ("mm: pagewalk: Take the pagetable lock in walk_pte_range()") * New patch fixing conflict with above patch * Squashed in fix for ordering of "static const" * Squashed in fix checking p*d_present() * New patch fixing termination condition for walk_pte_range() Changes since v14: https://lore.kernel.org/lkml/20191028135910.33253-1-steven.price@arm.com/ * Switch walk_page_range() into two functions, the existing walk_page_range() now still requires VMAs (and treats areas without a VMA as a 'hole'). The new walk_page_range_novma() ignores VMAs and will report the actual page table layout. This fixes the previous breakage of /proc//pagemap * New patch at the end of the series which reduces the 'level' numbers by 1 to simplify the code slightly * Added tags Changes since v13: https://lore.kernel.org/lkml/20191024093716.49420-1-steven.price@arm.com/ * Fixed typo in arc definition of pmd_leaf() spotted by the kbuild test robot * Added tags Changes since v12: https://lore.kernel.org/lkml/20191018101248.33727-1-steven.price@arm.com/ * Correct code format in riscv pud_leaf()/pmd_leaf() * v12 may not have reached everyone because of mail server problems (which are now hopefully resolved!) Changes since v11: https://lore.kernel.org/lkml/20191007153822.16518-1-steven.price@arm.com/ * Use "-1" as dummy depth parameter in patch 14. Changes since v10: https://lore.kernel.org/lkml/20190731154603.41797-1-steven.price@arm.com/ * Rebased to v5.4-rc1 - mainly various updates to deal with the splitting out of ops from struct mm_walk. * Deal with PGD_LEVEL_MULT not always being constant on x86. Changes since v9: https://lore.kernel.org/lkml/20190722154210.42799-1-steven.price@arm.com/ * Moved generic macros to first page in the series and explained the macro naming in the commit message. * mips: Moved macros to pgtable.h as they are now valid for both 32 and 64 bit * x86: Dropped patch which changed the debugfs output for x86, instead we have... * new patch adding 'depth' parameter to pte_hole. This is used to provide the necessary information to output lines for 'holes' in the debugfs files * new patch changing arm64 debugfs output to include holes to match x86 * generic ptdump KASAN handling has been simplified and now works with CONFIG_DEBUG_VIRTUAL. Changes since v8: https://lore.kernel.org/lkml/20190403141627.11664-1-steven.price@arm.com/ * Rename from p?d_large() to p?d_leaf() * Dropped patches migrating arm64/x86 custom walkers to walk_page_range() in favour of adding a generic PTDUMP implementation and migrating arm64/x86 to that instead. * Rebased to v5.3-rc1 Steven Price (25): mm: Add generic p?d_leaf() macros arc: mm: Add p?d_leaf() definitions arm: mm: Add p?d_leaf() definitions arm64: mm: Add p?d_leaf() definitions mips: mm: Add p?d_leaf() definitions powerpc: mm: Add p?d_leaf() definitions riscv: mm: Add p?d_leaf() definitions s390: mm: Add p?d_leaf() definitions sparc: mm: Add p?d_leaf() definitions x86: mm: Add p?d_leaf() definitions mm: pagewalk: Add p4d_entry() and pgd_entry() mm: pagewalk: Allow walking without vma mm: pagewalk: Don't lock PTEs for walk_page_range_novma() mm: pagewalk: fix termination condition in walk_pte_range() mm: pagewalk: Add test_p?d callbacks mm: pagewalk: Add 'depth' parameter to pte_hole x86: mm: Point to struct seq_file from struct pg_state x86: mm+efi: Convert ptdump_walk_pgd_level() to take a mm_struct x86: mm: Convert ptdump_walk_pgd_level_debugfs() to take an mm_struct x86: mm: Convert ptdump_walk_pgd_level_core() to take an mm_struct mm: Add generic ptdump x86: mm: Convert dump_pagetables to use walk_page_range arm64: mm: Convert mm/dump.c to use walk_page_range() arm64: mm: Display non-present entries in ptdump mm: ptdump: Reduce level numbers by 1 in note_page() arch/arc/include/asm/pgtable.h | 1 + arch/arm/include/asm/pgtable-2level.h | 1 + arch/arm/include/asm/pgtable-3level.h | 1 + arch/arm64/Kconfig | 1 + arch/arm64/Kconfig.debug | 19 +- arch/arm64/include/asm/pgtable.h | 2 + arch/arm64/include/asm/ptdump.h | 8 +- arch/arm64/mm/Makefile | 4 +- arch/arm64/mm/dump.c | 148 +++----- arch/arm64/mm/mmu.c | 4 +- arch/arm64/mm/ptdump_debugfs.c | 2 +- arch/mips/include/asm/pgtable.h | 5 + arch/powerpc/include/asm/book3s/64/pgtable.h | 30 +- arch/riscv/include/asm/pgtable-64.h | 7 + arch/riscv/include/asm/pgtable.h | 7 + arch/s390/include/asm/pgtable.h | 2 + arch/sparc/include/asm/pgtable_64.h | 2 + arch/x86/Kconfig | 1 + arch/x86/Kconfig.debug | 20 +- arch/x86/include/asm/pgtable.h | 10 +- arch/x86/mm/Makefile | 4 +- arch/x86/mm/debug_pagetables.c | 8 +- arch/x86/mm/dump_pagetables.c | 343 +++++-------------- arch/x86/platform/efi/efi_32.c | 2 +- arch/x86/platform/efi/efi_64.c | 4 +- drivers/firmware/efi/arm-runtime.c | 2 +- fs/proc/task_mmu.c | 4 +- include/asm-generic/pgtable.h | 20 ++ include/linux/pagewalk.h | 42 ++- include/linux/ptdump.h | 22 ++ mm/Kconfig.debug | 21 ++ mm/Makefile | 1 + mm/hmm.c | 8 +- mm/migrate.c | 5 +- mm/mincore.c | 1 + mm/pagewalk.c | 145 ++++++-- mm/ptdump.c | 151 ++++++++ 37 files changed, 600 insertions(+), 458 deletions(-) create mode 100644 include/linux/ptdump.h create mode 100644 mm/ptdump.c -- 2.20.1