summaryrefslogtreecommitdiffstats
path: root/arch/arm64/mm/copypage.c
Commit message (Collapse)AuthorAgeFilesLines
* arm64: mte: reset the page tag in page->flagsVincenzo Frascino2020-12-221-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hardware tag-based KASAN for compatibility with the other modes stores the tag associated to a page in page->flags. Due to this the kernel faults on access when it allocates a page with an initial tag and the user changes the tags. Reset the tag associated by the kernel to a page in all the meaningful places to prevent kernel faults on access. Note: An alternative to this approach could be to modify page_to_virt(). This though could end up being racy, in fact if a CPU checks the PG_mte_tagged bit and decides that the page is not tagged but another CPU maps the same with PROT_MTE and becomes tagged the subsequent kernel access would fail. Link: https://lkml.kernel.org/r/9073d4e973747a6f78d5bdd7ebe17f290d087096.1606161801.git.andreyknvl@google.com Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Marco Elver <elver@google.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* arm64: Avoid unnecessary clear_user_page() indirectionCatalin Marinas2020-09-041-6/+0
| | | | | | | | Since clear_user_page() calls clear_page() directly, avoid the unnecessary indirection. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
* arm64: mte: Tags-aware copy_{user_,}highpage() implementationsVincenzo Frascino2020-09-041-4/+21
| | | | | | | | | | | | | | | | When the Memory Tagging Extension is enabled, the tags need to be preserved across page copy (e.g. for copy-on-write, page migration). Introduce MTE-aware copy_{user_,}highpage() functions to copy tags to the destination if the source page has the PG_mte_tagged flag set. copy_user_page() does not need to handle tag copying since, with this patch, it is only called by the DAX code where there is no source page structure (and no source tags). Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Co-developed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234Thomas Gleixner2019-06-191-12/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* arm64: Defer dcache flush in __cpu_copy_user_pageAshok Kumar2015-12-171-1/+2
| | | | | | | | | Defer dcache flushing to __sync_icache_dcache by calling flush_dcache_page which clears PG_dcache_clean flag. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ashok Kumar <ashoks@broadcom.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
* arm64: export __cpu_{clear,copy}_user_page functionsMark Salter2014-07-081-0/+2
| | | | | | | | | The __cpu_clear_user_page() and __cpu_copy_user_page() functions are not currently exported. This prevents modules from using clear_user_page() and copy_user_page(). Signed-off-by: Mark Salter <msalter@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* arm64: MMU fault handling and page table managementCatalin Marinas2012-09-171-0/+34
This patch adds support for the handling of the MMU faults (exception entry code introduced by a previous patch) and page table management. The user translation table is pointed to by TTBR0 and the kernel one (swapper_pg_dir) by TTBR1. There is no translation information shared or address space overlapping between user and kernel page tables. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>