linux_dsm_epyc7002/arch/arm64/mm/kasan_init.c

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/*
* This file contains kasan initialization code for ARM64.
*
* Copyright (c) 2015 Samsung Electronics Co., Ltd.
* Author: Andrey Ryabinin <ryabinin.a.a@gmail.com>
*
* 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.
*
*/
#define pr_fmt(fmt) "kasan: " fmt
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#include <linux/bootmem.h>
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#include <linux/kasan.h>
#include <linux/kernel.h>
#include <linux/sched/task.h>
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#include <linux/memblock.h>
#include <linux/start_kernel.h>
#include <linux/mm.h>
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arm64: kasan: avoid TLB conflicts The page table modification performed during the KASAN init risks the allocation of conflicting TLB entries, as it swaps a set of valid global entries for another without suitable TLB maintenance. The presence of conflicting TLB entries can result in the delivery of synchronous TLB conflict aborts, or may result in the use of erroneous data being returned in response to a TLB lookup. This can affect explicit data accesses from software as well as translations performed asynchronously (e.g. as part of page table walks or speculative I-cache fetches), and can therefore result in a wide variety of problems. To avoid this, use cpu_replace_ttbr1 to swap the page tables. This ensures that when the new tables are installed there are no stale entries from the old tables which may conflict. As all updates are made to the tables while they are not active, the updates themselves are safe. At the same time, add the missing barrier to ensure that the tmp_pg_dir entries updated via memcpy are visible to the page table walkers at the point the tmp_pg_dir is installed. All other page table updates made as part of KASAN initialisation have the requisite barriers due to the use of the standard page table accessors. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-25 18:45:02 +07:00
#include <asm/mmu_context.h>
#include <asm/kernel-pgtable.h>
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#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
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#include <asm/tlbflush.h>
static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE);
/*
* The p*d_populate functions call virt_to_phys implicitly so they can't be used
* directly on kernel symbols (bm_p*d). All the early functions are called too
* early to use lm_alias so __p*d_populate functions must be used to populate
* with the physical address from __pa_symbol.
*/
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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static phys_addr_t __init kasan_alloc_zeroed_page(int node)
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{
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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void *p = memblock_virt_alloc_try_nid(PAGE_SIZE, PAGE_SIZE,
__pa(MAX_DMA_ADDRESS),
MEMBLOCK_ALLOC_ACCESSIBLE, node);
return __pa(p);
}
static pte_t *__init kasan_pte_offset(pmd_t *pmdp, unsigned long addr, int node,
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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bool early)
{
if (pmd_none(READ_ONCE(*pmdp))) {
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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phys_addr_t pte_phys = early ? __pa_symbol(kasan_zero_pte)
: kasan_alloc_zeroed_page(node);
__pmd_populate(pmdp, pte_phys, PMD_TYPE_TABLE);
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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}
return early ? pte_offset_kimg(pmdp, addr)
: pte_offset_kernel(pmdp, addr);
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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}
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static pmd_t *__init kasan_pmd_offset(pud_t *pudp, unsigned long addr, int node,
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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bool early)
{
if (pud_none(READ_ONCE(*pudp))) {
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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phys_addr_t pmd_phys = early ? __pa_symbol(kasan_zero_pmd)
: kasan_alloc_zeroed_page(node);
__pud_populate(pudp, pmd_phys, PMD_TYPE_TABLE);
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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}
return early ? pmd_offset_kimg(pudp, addr) : pmd_offset(pudp, addr);
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
}
static pud_t *__init kasan_pud_offset(pgd_t *pgdp, unsigned long addr, int node,
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
bool early)
{
if (pgd_none(READ_ONCE(*pgdp))) {
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
phys_addr_t pud_phys = early ? __pa_symbol(kasan_zero_pud)
: kasan_alloc_zeroed_page(node);
__pgd_populate(pgdp, pud_phys, PMD_TYPE_TABLE);
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
}
return early ? pud_offset_kimg(pgdp, addr) : pud_offset(pgdp, addr);
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
}
static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr,
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
unsigned long end, int node, bool early)
{
unsigned long next;
pte_t *ptep = kasan_pte_offset(pmdp, addr, node, early);
2015-10-12 22:52:58 +07:00
do {
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
phys_addr_t page_phys = early ? __pa_symbol(kasan_zero_page)
: kasan_alloc_zeroed_page(node);
2015-10-12 22:52:58 +07:00
next = addr + PAGE_SIZE;
set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL));
} while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep)));
2015-10-12 22:52:58 +07:00
}
static void __init kasan_pmd_populate(pud_t *pudp, unsigned long addr,
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
unsigned long end, int node, bool early)
2015-10-12 22:52:58 +07:00
{
unsigned long next;
pmd_t *pmdp = kasan_pmd_offset(pudp, addr, node, early);
2015-10-12 22:52:58 +07:00
do {
next = pmd_addr_end(addr, end);
kasan_pte_populate(pmdp, addr, next, node, early);
} while (pmdp++, addr = next, addr != end && pmd_none(READ_ONCE(*pmdp)));
2015-10-12 22:52:58 +07:00
}
static void __init kasan_pud_populate(pgd_t *pgdp, unsigned long addr,
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
unsigned long end, int node, bool early)
2015-10-12 22:52:58 +07:00
{
unsigned long next;
pud_t *pudp = kasan_pud_offset(pgdp, addr, node, early);
2015-10-12 22:52:58 +07:00
do {
next = pud_addr_end(addr, end);
kasan_pmd_populate(pudp, addr, next, node, early);
} while (pudp++, addr = next, addr != end && pud_none(READ_ONCE(*pudp)));
2015-10-12 22:52:58 +07:00
}
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
static void __init kasan_pgd_populate(unsigned long addr, unsigned long end,
int node, bool early)
2015-10-12 22:52:58 +07:00
{
unsigned long next;
pgd_t *pgdp;
2015-10-12 22:52:58 +07:00
pgdp = pgd_offset_k(addr);
2015-10-12 22:52:58 +07:00
do {
next = pgd_addr_end(addr, end);
kasan_pud_populate(pgdp, addr, next, node, early);
} while (pgdp++, addr = next, addr != end);
2015-10-12 22:52:58 +07:00
}
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
/* The early shadow maps everything to a single page of zeroes */
asmlinkage void __init kasan_early_init(void)
2015-10-12 22:52:58 +07:00
{
BUILD_BUG_ON(KASAN_SHADOW_OFFSET !=
KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT)));
2015-10-12 22:52:58 +07:00
BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PGDIR_SIZE));
BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE));
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
kasan_pgd_populate(KASAN_SHADOW_START, KASAN_SHADOW_END, NUMA_NO_NODE,
true);
}
/* Set up full kasan mappings, ensuring that the mapped pages are zeroed */
static void __init kasan_map_populate(unsigned long start, unsigned long end,
int node)
{
kasan_pgd_populate(start & PAGE_MASK, PAGE_ALIGN(end), node, false);
2015-10-12 22:52:58 +07:00
}
arm64: mm: create new fine-grained mappings at boot At boot we may change the granularity of the tables mapping the kernel (by splitting or making sections). This may happen when we create the linear mapping (in __map_memblock), or at any point we try to apply fine-grained permissions to the kernel (e.g. fixup_executable, mark_rodata_ro, fixup_init). Changing the active page tables in this manner may result in multiple entries for the same address being allocated into TLBs, risking problems such as TLB conflict aborts or issues derived from the amalgamation of TLB entries. Generally, a break-before-make (BBM) approach is necessary to avoid conflicts, but we cannot do this for the kernel tables as it risks unmapping text or data being used to do so. Instead, we can create a new set of tables from scratch in the safety of the existing mappings, and subsequently migrate over to these using the new cpu_replace_ttbr1 helper, which avoids the two sets of tables being active simultaneously. To avoid issues when we later modify permissions of the page tables (e.g. in fixup_init), we must create the page tables at a granularity such that later modification does not result in splitting of tables. This patch applies this strategy, creating a new set of fine-grained page tables from scratch, and safely migrating to them. The existing fixmap and kasan shadow page tables are reused in the new fine-grained tables. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-25 18:45:12 +07:00
/*
* Copy the current shadow region into a new pgdir.
*/
void __init kasan_copy_shadow(pgd_t *pgdir)
{
pgd_t *pgdp, *pgdp_new, *pgdp_end;
arm64: mm: create new fine-grained mappings at boot At boot we may change the granularity of the tables mapping the kernel (by splitting or making sections). This may happen when we create the linear mapping (in __map_memblock), or at any point we try to apply fine-grained permissions to the kernel (e.g. fixup_executable, mark_rodata_ro, fixup_init). Changing the active page tables in this manner may result in multiple entries for the same address being allocated into TLBs, risking problems such as TLB conflict aborts or issues derived from the amalgamation of TLB entries. Generally, a break-before-make (BBM) approach is necessary to avoid conflicts, but we cannot do this for the kernel tables as it risks unmapping text or data being used to do so. Instead, we can create a new set of tables from scratch in the safety of the existing mappings, and subsequently migrate over to these using the new cpu_replace_ttbr1 helper, which avoids the two sets of tables being active simultaneously. To avoid issues when we later modify permissions of the page tables (e.g. in fixup_init), we must create the page tables at a granularity such that later modification does not result in splitting of tables. This patch applies this strategy, creating a new set of fine-grained page tables from scratch, and safely migrating to them. The existing fixmap and kasan shadow page tables are reused in the new fine-grained tables. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-25 18:45:12 +07:00
pgdp = pgd_offset_k(KASAN_SHADOW_START);
pgdp_end = pgd_offset_k(KASAN_SHADOW_END);
pgdp_new = pgd_offset_raw(pgdir, KASAN_SHADOW_START);
arm64: mm: create new fine-grained mappings at boot At boot we may change the granularity of the tables mapping the kernel (by splitting or making sections). This may happen when we create the linear mapping (in __map_memblock), or at any point we try to apply fine-grained permissions to the kernel (e.g. fixup_executable, mark_rodata_ro, fixup_init). Changing the active page tables in this manner may result in multiple entries for the same address being allocated into TLBs, risking problems such as TLB conflict aborts or issues derived from the amalgamation of TLB entries. Generally, a break-before-make (BBM) approach is necessary to avoid conflicts, but we cannot do this for the kernel tables as it risks unmapping text or data being used to do so. Instead, we can create a new set of tables from scratch in the safety of the existing mappings, and subsequently migrate over to these using the new cpu_replace_ttbr1 helper, which avoids the two sets of tables being active simultaneously. To avoid issues when we later modify permissions of the page tables (e.g. in fixup_init), we must create the page tables at a granularity such that later modification does not result in splitting of tables. This patch applies this strategy, creating a new set of fine-grained page tables from scratch, and safely migrating to them. The existing fixmap and kasan shadow page tables are reused in the new fine-grained tables. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-25 18:45:12 +07:00
do {
set_pgd(pgdp_new, READ_ONCE(*pgdp));
} while (pgdp++, pgdp_new++, pgdp != pgdp_end);
arm64: mm: create new fine-grained mappings at boot At boot we may change the granularity of the tables mapping the kernel (by splitting or making sections). This may happen when we create the linear mapping (in __map_memblock), or at any point we try to apply fine-grained permissions to the kernel (e.g. fixup_executable, mark_rodata_ro, fixup_init). Changing the active page tables in this manner may result in multiple entries for the same address being allocated into TLBs, risking problems such as TLB conflict aborts or issues derived from the amalgamation of TLB entries. Generally, a break-before-make (BBM) approach is necessary to avoid conflicts, but we cannot do this for the kernel tables as it risks unmapping text or data being used to do so. Instead, we can create a new set of tables from scratch in the safety of the existing mappings, and subsequently migrate over to these using the new cpu_replace_ttbr1 helper, which avoids the two sets of tables being active simultaneously. To avoid issues when we later modify permissions of the page tables (e.g. in fixup_init), we must create the page tables at a granularity such that later modification does not result in splitting of tables. This patch applies this strategy, creating a new set of fine-grained page tables from scratch, and safely migrating to them. The existing fixmap and kasan shadow page tables are reused in the new fine-grained tables. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-25 18:45:12 +07:00
}
2015-10-12 22:52:58 +07:00
static void __init clear_pgds(unsigned long start,
unsigned long end)
{
/*
* Remove references to kasan page tables from
* swapper_pg_dir. pgd_clear() can't be used
* here because it's nop on 2,3-level pagetable setups
*/
for (; start < end; start += PGDIR_SIZE)
set_pgd(pgd_offset_k(start), __pgd(0));
}
void __init kasan_init(void)
{
u64 kimg_shadow_start, kimg_shadow_end;
arm64: add support for kernel ASLR This adds support for KASLR is implemented, based on entropy provided by the bootloader in the /chosen/kaslr-seed DT property. Depending on the size of the address space (VA_BITS) and the page size, the entropy in the virtual displacement is up to 13 bits (16k/2 levels) and up to 25 bits (all 4 levels), with the sidenote that displacements that result in the kernel image straddling a 1GB/32MB/512MB alignment boundary (for 4KB/16KB/64KB granule kernels, respectively) are not allowed, and will be rounded up to an acceptable value. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is enabled, the module region is randomized independently from the core kernel. This makes it less likely that the location of core kernel data structures can be determined by an adversary, but causes all function calls from modules into the core kernel to be resolved via entries in the module PLTs. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is not enabled, the module region is randomized by choosing a page aligned 128 MB region inside the interval [_etext - 128 MB, _stext + 128 MB). This gives between 10 and 14 bits of entropy (depending on page size), independently of the kernel randomization, but still guarantees that modules are within the range of relative branch and jump instructions (with the caveat that, since the module region is shared with other uses of the vmalloc area, modules may need to be loaded further away if the module region is exhausted) Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-26 20:12:01 +07:00
u64 mod_shadow_start, mod_shadow_end;
2015-10-12 22:52:58 +07:00
struct memblock_region *reg;
int i;
2015-10-12 22:52:58 +07:00
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
kimg_shadow_start = (u64)kasan_mem_to_shadow(_text) & PAGE_MASK;
kimg_shadow_end = PAGE_ALIGN((u64)kasan_mem_to_shadow(_end));
arm64: add support for kernel ASLR This adds support for KASLR is implemented, based on entropy provided by the bootloader in the /chosen/kaslr-seed DT property. Depending on the size of the address space (VA_BITS) and the page size, the entropy in the virtual displacement is up to 13 bits (16k/2 levels) and up to 25 bits (all 4 levels), with the sidenote that displacements that result in the kernel image straddling a 1GB/32MB/512MB alignment boundary (for 4KB/16KB/64KB granule kernels, respectively) are not allowed, and will be rounded up to an acceptable value. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is enabled, the module region is randomized independently from the core kernel. This makes it less likely that the location of core kernel data structures can be determined by an adversary, but causes all function calls from modules into the core kernel to be resolved via entries in the module PLTs. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is not enabled, the module region is randomized by choosing a page aligned 128 MB region inside the interval [_etext - 128 MB, _stext + 128 MB). This gives between 10 and 14 bits of entropy (depending on page size), independently of the kernel randomization, but still guarantees that modules are within the range of relative branch and jump instructions (with the caveat that, since the module region is shared with other uses of the vmalloc area, modules may need to be loaded further away if the module region is exhausted) Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-26 20:12:01 +07:00
mod_shadow_start = (u64)kasan_mem_to_shadow((void *)MODULES_VADDR);
mod_shadow_end = (u64)kasan_mem_to_shadow((void *)MODULES_END);
2015-10-12 22:52:58 +07:00
/*
* We are going to perform proper setup of shadow memory.
* At first we should unmap early shadow (clear_pgds() call below).
2015-10-12 22:52:58 +07:00
* However, instrumented code couldn't execute without shadow memory.
* tmp_pg_dir used to keep early shadow mapped until full shadow
* setup will be finished.
*/
memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(tmp_pg_dir));
arm64: kasan: avoid TLB conflicts The page table modification performed during the KASAN init risks the allocation of conflicting TLB entries, as it swaps a set of valid global entries for another without suitable TLB maintenance. The presence of conflicting TLB entries can result in the delivery of synchronous TLB conflict aborts, or may result in the use of erroneous data being returned in response to a TLB lookup. This can affect explicit data accesses from software as well as translations performed asynchronously (e.g. as part of page table walks or speculative I-cache fetches), and can therefore result in a wide variety of problems. To avoid this, use cpu_replace_ttbr1 to swap the page tables. This ensures that when the new tables are installed there are no stale entries from the old tables which may conflict. As all updates are made to the tables while they are not active, the updates themselves are safe. At the same time, add the missing barrier to ensure that the tmp_pg_dir entries updated via memcpy are visible to the page table walkers at the point the tmp_pg_dir is installed. All other page table updates made as part of KASAN initialisation have the requisite barriers due to the use of the standard page table accessors. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-25 18:45:02 +07:00
dsb(ishst);
cpu_replace_ttbr1(lm_alias(tmp_pg_dir));
2015-10-12 22:52:58 +07:00
clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
kasan_map_populate(kimg_shadow_start, kimg_shadow_end,
arm64: kasan: avoid pfn_to_nid() before page array is initialized In arm64's kasan_init(), we use pfn_to_nid() to find the NUMA node a span of memory is in, hoping to allocate shadow from the same NUMA node. However, at this point, the page array has not been initialized, and thus this is bogus. Since commit: f165b378bbdf6c8a ("mm: uninitialized struct page poisoning sanity") ... accessing fields of the page array results in a boot time Oops(), highlighting this problem: [ 0.000000] Unable to handle kernel paging request at virtual address dfff200000000000 [ 0.000000] Mem abort info: [ 0.000000] ESR = 0x96000004 [ 0.000000] Exception class = DABT (current EL), IL = 32 bits [ 0.000000] SET = 0, FnV = 0 [ 0.000000] EA = 0, S1PTW = 0 [ 0.000000] Data abort info: [ 0.000000] ISV = 0, ISS = 0x00000004 [ 0.000000] CM = 0, WnR = 0 [ 0.000000] [dfff200000000000] address between user and kernel address ranges [ 0.000000] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.16.0-07317-gf165b378bbdf #42 [ 0.000000] Hardware name: ARM Juno development board (r1) (DT) [ 0.000000] pstate: 80000085 (Nzcv daIf -PAN -UAO) [ 0.000000] pc : __asan_load8+0x8c/0xa8 [ 0.000000] lr : __dump_page+0x3c/0x3b8 [ 0.000000] sp : ffff2000099b7ca0 [ 0.000000] x29: ffff2000099b7ca0 x28: ffff20000a1762c0 [ 0.000000] x27: ffff7e0000000000 x26: ffff2000099dd000 [ 0.000000] x25: ffff200009a3f960 x24: ffff200008f9c38c [ 0.000000] x23: ffff20000a9d3000 x22: ffff200009735430 [ 0.000000] x21: fffffffffffffffe x20: ffff7e0001e50420 [ 0.000000] x19: ffff7e0001e50400 x18: 0000000000001840 [ 0.000000] x17: ffffffffffff8270 x16: 0000000000001840 [ 0.000000] x15: 0000000000001920 x14: 0000000000000004 [ 0.000000] x13: 0000000000000000 x12: 0000000000000800 [ 0.000000] x11: 1ffff0012d0f89ff x10: ffff10012d0f89ff [ 0.000000] x9 : 0000000000000000 x8 : ffff8009687c5000 [ 0.000000] x7 : 0000000000000000 x6 : ffff10000f282000 [ 0.000000] x5 : 0000000000000040 x4 : fffffffffffffffe [ 0.000000] x3 : 0000000000000000 x2 : dfff200000000000 [ 0.000000] x1 : 0000000000000005 x0 : 0000000000000000 [ 0.000000] Process swapper (pid: 0, stack limit = 0x (ptrval)) [ 0.000000] Call trace: [ 0.000000] __asan_load8+0x8c/0xa8 [ 0.000000] __dump_page+0x3c/0x3b8 [ 0.000000] dump_page+0xc/0x18 [ 0.000000] kasan_init+0x2e8/0x5a8 [ 0.000000] setup_arch+0x294/0x71c [ 0.000000] start_kernel+0xdc/0x500 [ 0.000000] Code: aa0403e0 9400063c 17ffffee d343fc00 (38e26800) [ 0.000000] ---[ end trace 67064f0e9c0cc338 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- Let's fix this by using early_pfn_to_nid(), as other architectures do in their kasan init code. Note that early_pfn_to_nid acquires the nid from the memblock array, which we iterate over in kasan_init(), so this should be fine. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Fixes: 39d114ddc6822302 ("arm64: add KASAN support") Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-04-16 20:44:41 +07:00
early_pfn_to_nid(virt_to_pfn(lm_alias(_text))));
2015-10-12 22:52:58 +07:00
kasan_populate_zero_shadow((void *)KASAN_SHADOW_START,
arm64: add support for kernel ASLR This adds support for KASLR is implemented, based on entropy provided by the bootloader in the /chosen/kaslr-seed DT property. Depending on the size of the address space (VA_BITS) and the page size, the entropy in the virtual displacement is up to 13 bits (16k/2 levels) and up to 25 bits (all 4 levels), with the sidenote that displacements that result in the kernel image straddling a 1GB/32MB/512MB alignment boundary (for 4KB/16KB/64KB granule kernels, respectively) are not allowed, and will be rounded up to an acceptable value. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is enabled, the module region is randomized independently from the core kernel. This makes it less likely that the location of core kernel data structures can be determined by an adversary, but causes all function calls from modules into the core kernel to be resolved via entries in the module PLTs. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is not enabled, the module region is randomized by choosing a page aligned 128 MB region inside the interval [_etext - 128 MB, _stext + 128 MB). This gives between 10 and 14 bits of entropy (depending on page size), independently of the kernel randomization, but still guarantees that modules are within the range of relative branch and jump instructions (with the caveat that, since the module region is shared with other uses of the vmalloc area, modules may need to be loaded further away if the module region is exhausted) Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-26 20:12:01 +07:00
(void *)mod_shadow_start);
kasan_populate_zero_shadow((void *)kimg_shadow_end,
arm64: add support for kernel ASLR This adds support for KASLR is implemented, based on entropy provided by the bootloader in the /chosen/kaslr-seed DT property. Depending on the size of the address space (VA_BITS) and the page size, the entropy in the virtual displacement is up to 13 bits (16k/2 levels) and up to 25 bits (all 4 levels), with the sidenote that displacements that result in the kernel image straddling a 1GB/32MB/512MB alignment boundary (for 4KB/16KB/64KB granule kernels, respectively) are not allowed, and will be rounded up to an acceptable value. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is enabled, the module region is randomized independently from the core kernel. This makes it less likely that the location of core kernel data structures can be determined by an adversary, but causes all function calls from modules into the core kernel to be resolved via entries in the module PLTs. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is not enabled, the module region is randomized by choosing a page aligned 128 MB region inside the interval [_etext - 128 MB, _stext + 128 MB). This gives between 10 and 14 bits of entropy (depending on page size), independently of the kernel randomization, but still guarantees that modules are within the range of relative branch and jump instructions (with the caveat that, since the module region is shared with other uses of the vmalloc area, modules may need to be loaded further away if the module region is exhausted) Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-26 20:12:01 +07:00
kasan_mem_to_shadow((void *)PAGE_OFFSET));
if (kimg_shadow_start > mod_shadow_end)
kasan_populate_zero_shadow((void *)mod_shadow_end,
(void *)kimg_shadow_start);
2015-10-12 22:52:58 +07:00
for_each_memblock(memory, reg) {
void *start = (void *)__phys_to_virt(reg->base);
void *end = (void *)__phys_to_virt(reg->base + reg->size);
if (start >= end)
break;
arm64/mm/kasan: don't use vmemmap_populate() to initialize shadow The kasan shadow is currently mapped using vmemmap_populate() since that provides a semi-convenient way to map pages into init_top_pgt. However, since that no longer zeroes the mapped pages, it is not suitable for kasan, which requires zeroed shadow memory. Add kasan_populate_shadow() interface and use it instead of vmemmap_populate(). Besides, this allows us to take advantage of gigantic pages and use them to populate the shadow, which should save us some memory wasted on page tables and reduce TLB pressure. Link: http://lkml.kernel.org/r/20171103185147.2688-3-pasha.tatashin@oracle.com Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Alexander Potapenko <glider@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-16 08:36:40 +07:00
kasan_map_populate((unsigned long)kasan_mem_to_shadow(start),
(unsigned long)kasan_mem_to_shadow(end),
arm64: kasan: avoid pfn_to_nid() before page array is initialized In arm64's kasan_init(), we use pfn_to_nid() to find the NUMA node a span of memory is in, hoping to allocate shadow from the same NUMA node. However, at this point, the page array has not been initialized, and thus this is bogus. Since commit: f165b378bbdf6c8a ("mm: uninitialized struct page poisoning sanity") ... accessing fields of the page array results in a boot time Oops(), highlighting this problem: [ 0.000000] Unable to handle kernel paging request at virtual address dfff200000000000 [ 0.000000] Mem abort info: [ 0.000000] ESR = 0x96000004 [ 0.000000] Exception class = DABT (current EL), IL = 32 bits [ 0.000000] SET = 0, FnV = 0 [ 0.000000] EA = 0, S1PTW = 0 [ 0.000000] Data abort info: [ 0.000000] ISV = 0, ISS = 0x00000004 [ 0.000000] CM = 0, WnR = 0 [ 0.000000] [dfff200000000000] address between user and kernel address ranges [ 0.000000] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.16.0-07317-gf165b378bbdf #42 [ 0.000000] Hardware name: ARM Juno development board (r1) (DT) [ 0.000000] pstate: 80000085 (Nzcv daIf -PAN -UAO) [ 0.000000] pc : __asan_load8+0x8c/0xa8 [ 0.000000] lr : __dump_page+0x3c/0x3b8 [ 0.000000] sp : ffff2000099b7ca0 [ 0.000000] x29: ffff2000099b7ca0 x28: ffff20000a1762c0 [ 0.000000] x27: ffff7e0000000000 x26: ffff2000099dd000 [ 0.000000] x25: ffff200009a3f960 x24: ffff200008f9c38c [ 0.000000] x23: ffff20000a9d3000 x22: ffff200009735430 [ 0.000000] x21: fffffffffffffffe x20: ffff7e0001e50420 [ 0.000000] x19: ffff7e0001e50400 x18: 0000000000001840 [ 0.000000] x17: ffffffffffff8270 x16: 0000000000001840 [ 0.000000] x15: 0000000000001920 x14: 0000000000000004 [ 0.000000] x13: 0000000000000000 x12: 0000000000000800 [ 0.000000] x11: 1ffff0012d0f89ff x10: ffff10012d0f89ff [ 0.000000] x9 : 0000000000000000 x8 : ffff8009687c5000 [ 0.000000] x7 : 0000000000000000 x6 : ffff10000f282000 [ 0.000000] x5 : 0000000000000040 x4 : fffffffffffffffe [ 0.000000] x3 : 0000000000000000 x2 : dfff200000000000 [ 0.000000] x1 : 0000000000000005 x0 : 0000000000000000 [ 0.000000] Process swapper (pid: 0, stack limit = 0x (ptrval)) [ 0.000000] Call trace: [ 0.000000] __asan_load8+0x8c/0xa8 [ 0.000000] __dump_page+0x3c/0x3b8 [ 0.000000] dump_page+0xc/0x18 [ 0.000000] kasan_init+0x2e8/0x5a8 [ 0.000000] setup_arch+0x294/0x71c [ 0.000000] start_kernel+0xdc/0x500 [ 0.000000] Code: aa0403e0 9400063c 17ffffee d343fc00 (38e26800) [ 0.000000] ---[ end trace 67064f0e9c0cc338 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- Let's fix this by using early_pfn_to_nid(), as other architectures do in their kasan init code. Note that early_pfn_to_nid acquires the nid from the memblock array, which we iterate over in kasan_init(), so this should be fine. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Fixes: 39d114ddc6822302 ("arm64: add KASAN support") Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-04-16 20:44:41 +07:00
early_pfn_to_nid(virt_to_pfn(start)));
2015-10-12 22:52:58 +07:00
}
/*
* KAsan may reuse the contents of kasan_zero_pte directly, so we
* should make sure that it maps the zero page read-only.
*/
for (i = 0; i < PTRS_PER_PTE; i++)
set_pte(&kasan_zero_pte[i],
pfn_pte(sym_to_pfn(kasan_zero_page), PAGE_KERNEL_RO));
2015-10-12 22:52:58 +07:00
memset(kasan_zero_page, 0, PAGE_SIZE);
cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
2015-10-12 22:52:58 +07:00
/* At this point kasan is fully initialized. Enable error messages */
init_task.kasan_depth = 0;
pr_info("KernelAddressSanitizer initialized\n");
}