mirror of
https://github.com/torvalds/linux
synced 2024-10-06 19:34:19 +00:00
2321ba3e37
Patch series "mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with swap PTEs". This is the follow-up on [1]: [PATCH v2 0/8] mm: COW fixes part 3: reliable GUP R/W FOLL_GET of anonymous pages After we implemented __HAVE_ARCH_PTE_SWP_EXCLUSIVE on most prominent enterprise architectures, implement __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all remaining architectures that support swap PTEs. This makes sure that exclusive anonymous pages will stay exclusive, even after they were swapped out -- for example, making GUP R/W FOLL_GET of anonymous pages reliable. Details can be found in [1]. This primarily fixes remaining known O_DIRECT memory corruptions that can happen on concurrent swapout, whereby we can lose DMA reads to a page (modifying the user page by writing to it). To verify, there are two test cases (requiring swap space, obviously): (1) The O_DIRECT+swapout test case [2] from Andrea. This test case tries triggering a race condition. (2) My vmsplice() test case [3] that tries to detect if the exclusive marker was lost during swapout, not relying on a race condition. For example, on 32bit x86 (with and without PAE), my test case fails without these patches: $ ./test_swp_exclusive FAIL: page was replaced during COW But succeeds with these patches: $ ./test_swp_exclusive PASS: page was not replaced during COW Why implement __HAVE_ARCH_PTE_SWP_EXCLUSIVE for all architectures, even the ones where swap support might be in a questionable state? This is the first step towards removing "readable_exclusive" migration entries, and instead using pte_swp_exclusive() also with (readable) migration entries instead (as suggested by Peter). The only missing piece for that is supporting pmd_swp_exclusive() on relevant architectures with THP migration support. As all relevant architectures now implement __HAVE_ARCH_PTE_SWP_EXCLUSIVE,, we can drop __HAVE_ARCH_PTE_SWP_EXCLUSIVE in the last patch. I tried cross-compiling all relevant setups and tested on x86 and sparc64 so far. CCing arch maintainers only on this cover letter and on the respective patch(es). [1] https://lkml.kernel.org/r/20220329164329.208407-1-david@redhat.com [2] https://gitlab.com/aarcange/kernel-testcases-for-v5.11/-/blob/main/page_count_do_wp_page-swap.c [3] https://gitlab.com/davidhildenbrand/scratchspace/-/blob/main/test_swp_exclusive.c This patch (of 26): We want to implement __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures. Let's extend our sanity checks, especially testing that our PTE bit does not affect: * is_swap_pte() -> pte_present() and pte_none() * the swap entry + type * pte_swp_soft_dirty() Especially, the pfn_pte() is dodgy when the swap PTE layout differs heavily from ordinary PTEs. Let's properly construct a swap PTE from swap type+offset. [david@redhat.com: fix build] Link: https://lkml.kernel.org/r/6aaad548-cf48-77fa-9d6c-db83d724b2eb@redhat.com Link: https://lkml.kernel.org/r/20230113171026.582290-1-david@redhat.com Link: https://lkml.kernel.org/r/20230113171026.582290-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: <aou@eecs.berkeley.edu> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Brian Cain <bcain@quicinc.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Chris Zankel <chris@zankel.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Helge Deller <deller@gmx.de> Cc: H. Peter Anvin (Intel) <hpa@zytor.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Nadav Amit <namit@vmware.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xuerui Wang <kernel@xen0n.name> Cc: Yang Shi <shy828301@gmail.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
1409 lines
40 KiB
C
1409 lines
40 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* This kernel test validates architecture page table helpers and
|
|
* accessors and helps in verifying their continued compliance with
|
|
* expected generic MM semantics.
|
|
*
|
|
* Copyright (C) 2019 ARM Ltd.
|
|
*
|
|
* Author: Anshuman Khandual <anshuman.khandual@arm.com>
|
|
*/
|
|
#define pr_fmt(fmt) "debug_vm_pgtable: [%-25s]: " fmt, __func__
|
|
|
|
#include <linux/gfp.h>
|
|
#include <linux/highmem.h>
|
|
#include <linux/hugetlb.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/kconfig.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/mman.h>
|
|
#include <linux/mm_types.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pfn_t.h>
|
|
#include <linux/printk.h>
|
|
#include <linux/pgtable.h>
|
|
#include <linux/random.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/swapops.h>
|
|
#include <linux/start_kernel.h>
|
|
#include <linux/sched/mm.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/tlbflush.h>
|
|
|
|
/*
|
|
* Please refer Documentation/mm/arch_pgtable_helpers.rst for the semantics
|
|
* expectations that are being validated here. All future changes in here
|
|
* or the documentation need to be in sync.
|
|
*
|
|
* On s390 platform, the lower 4 bits are used to identify given page table
|
|
* entry type. But these bits might affect the ability to clear entries with
|
|
* pxx_clear() because of how dynamic page table folding works on s390. So
|
|
* while loading up the entries do not change the lower 4 bits. It does not
|
|
* have affect any other platform. Also avoid the 62nd bit on ppc64 that is
|
|
* used to mark a pte entry.
|
|
*/
|
|
#define S390_SKIP_MASK GENMASK(3, 0)
|
|
#if __BITS_PER_LONG == 64
|
|
#define PPC64_SKIP_MASK GENMASK(62, 62)
|
|
#else
|
|
#define PPC64_SKIP_MASK 0x0
|
|
#endif
|
|
#define ARCH_SKIP_MASK (S390_SKIP_MASK | PPC64_SKIP_MASK)
|
|
#define RANDOM_ORVALUE (GENMASK(BITS_PER_LONG - 1, 0) & ~ARCH_SKIP_MASK)
|
|
#define RANDOM_NZVALUE GENMASK(7, 0)
|
|
|
|
struct pgtable_debug_args {
|
|
struct mm_struct *mm;
|
|
struct vm_area_struct *vma;
|
|
|
|
pgd_t *pgdp;
|
|
p4d_t *p4dp;
|
|
pud_t *pudp;
|
|
pmd_t *pmdp;
|
|
pte_t *ptep;
|
|
|
|
p4d_t *start_p4dp;
|
|
pud_t *start_pudp;
|
|
pmd_t *start_pmdp;
|
|
pgtable_t start_ptep;
|
|
|
|
unsigned long vaddr;
|
|
pgprot_t page_prot;
|
|
pgprot_t page_prot_none;
|
|
|
|
bool is_contiguous_page;
|
|
unsigned long pud_pfn;
|
|
unsigned long pmd_pfn;
|
|
unsigned long pte_pfn;
|
|
|
|
unsigned long fixed_alignment;
|
|
unsigned long fixed_pgd_pfn;
|
|
unsigned long fixed_p4d_pfn;
|
|
unsigned long fixed_pud_pfn;
|
|
unsigned long fixed_pmd_pfn;
|
|
unsigned long fixed_pte_pfn;
|
|
};
|
|
|
|
static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx)
|
|
{
|
|
pgprot_t prot = vm_get_page_prot(idx);
|
|
pte_t pte = pfn_pte(args->fixed_pte_pfn, prot);
|
|
unsigned long val = idx, *ptr = &val;
|
|
|
|
pr_debug("Validating PTE basic (%pGv)\n", ptr);
|
|
|
|
/*
|
|
* This test needs to be executed after the given page table entry
|
|
* is created with pfn_pte() to make sure that vm_get_page_prot(idx)
|
|
* does not have the dirty bit enabled from the beginning. This is
|
|
* important for platforms like arm64 where (!PTE_RDONLY) indicate
|
|
* dirty bit being set.
|
|
*/
|
|
WARN_ON(pte_dirty(pte_wrprotect(pte)));
|
|
|
|
WARN_ON(!pte_same(pte, pte));
|
|
WARN_ON(!pte_young(pte_mkyoung(pte_mkold(pte))));
|
|
WARN_ON(!pte_dirty(pte_mkdirty(pte_mkclean(pte))));
|
|
WARN_ON(!pte_write(pte_mkwrite(pte_wrprotect(pte))));
|
|
WARN_ON(pte_young(pte_mkold(pte_mkyoung(pte))));
|
|
WARN_ON(pte_dirty(pte_mkclean(pte_mkdirty(pte))));
|
|
WARN_ON(pte_write(pte_wrprotect(pte_mkwrite(pte))));
|
|
WARN_ON(pte_dirty(pte_wrprotect(pte_mkclean(pte))));
|
|
WARN_ON(!pte_dirty(pte_wrprotect(pte_mkdirty(pte))));
|
|
}
|
|
|
|
static void __init pte_advanced_tests(struct pgtable_debug_args *args)
|
|
{
|
|
struct page *page;
|
|
pte_t pte;
|
|
|
|
/*
|
|
* Architectures optimize set_pte_at by avoiding TLB flush.
|
|
* This requires set_pte_at to be not used to update an
|
|
* existing pte entry. Clear pte before we do set_pte_at
|
|
*
|
|
* flush_dcache_page() is called after set_pte_at() to clear
|
|
* PG_arch_1 for the page on ARM64. The page flag isn't cleared
|
|
* when it's released and page allocation check will fail when
|
|
* the page is allocated again. For architectures other than ARM64,
|
|
* the unexpected overhead of cache flushing is acceptable.
|
|
*/
|
|
page = (args->pte_pfn != ULONG_MAX) ? pfn_to_page(args->pte_pfn) : NULL;
|
|
if (!page)
|
|
return;
|
|
|
|
pr_debug("Validating PTE advanced\n");
|
|
pte = pfn_pte(args->pte_pfn, args->page_prot);
|
|
set_pte_at(args->mm, args->vaddr, args->ptep, pte);
|
|
flush_dcache_page(page);
|
|
ptep_set_wrprotect(args->mm, args->vaddr, args->ptep);
|
|
pte = ptep_get(args->ptep);
|
|
WARN_ON(pte_write(pte));
|
|
ptep_get_and_clear(args->mm, args->vaddr, args->ptep);
|
|
pte = ptep_get(args->ptep);
|
|
WARN_ON(!pte_none(pte));
|
|
|
|
pte = pfn_pte(args->pte_pfn, args->page_prot);
|
|
pte = pte_wrprotect(pte);
|
|
pte = pte_mkclean(pte);
|
|
set_pte_at(args->mm, args->vaddr, args->ptep, pte);
|
|
flush_dcache_page(page);
|
|
pte = pte_mkwrite(pte);
|
|
pte = pte_mkdirty(pte);
|
|
ptep_set_access_flags(args->vma, args->vaddr, args->ptep, pte, 1);
|
|
pte = ptep_get(args->ptep);
|
|
WARN_ON(!(pte_write(pte) && pte_dirty(pte)));
|
|
ptep_get_and_clear_full(args->mm, args->vaddr, args->ptep, 1);
|
|
pte = ptep_get(args->ptep);
|
|
WARN_ON(!pte_none(pte));
|
|
|
|
pte = pfn_pte(args->pte_pfn, args->page_prot);
|
|
pte = pte_mkyoung(pte);
|
|
set_pte_at(args->mm, args->vaddr, args->ptep, pte);
|
|
flush_dcache_page(page);
|
|
ptep_test_and_clear_young(args->vma, args->vaddr, args->ptep);
|
|
pte = ptep_get(args->ptep);
|
|
WARN_ON(pte_young(pte));
|
|
|
|
ptep_get_and_clear_full(args->mm, args->vaddr, args->ptep, 1);
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx)
|
|
{
|
|
pgprot_t prot = vm_get_page_prot(idx);
|
|
unsigned long val = idx, *ptr = &val;
|
|
pmd_t pmd;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PMD basic (%pGv)\n", ptr);
|
|
pmd = pfn_pmd(args->fixed_pmd_pfn, prot);
|
|
|
|
/*
|
|
* This test needs to be executed after the given page table entry
|
|
* is created with pfn_pmd() to make sure that vm_get_page_prot(idx)
|
|
* does not have the dirty bit enabled from the beginning. This is
|
|
* important for platforms like arm64 where (!PTE_RDONLY) indicate
|
|
* dirty bit being set.
|
|
*/
|
|
WARN_ON(pmd_dirty(pmd_wrprotect(pmd)));
|
|
|
|
|
|
WARN_ON(!pmd_same(pmd, pmd));
|
|
WARN_ON(!pmd_young(pmd_mkyoung(pmd_mkold(pmd))));
|
|
WARN_ON(!pmd_dirty(pmd_mkdirty(pmd_mkclean(pmd))));
|
|
WARN_ON(!pmd_write(pmd_mkwrite(pmd_wrprotect(pmd))));
|
|
WARN_ON(pmd_young(pmd_mkold(pmd_mkyoung(pmd))));
|
|
WARN_ON(pmd_dirty(pmd_mkclean(pmd_mkdirty(pmd))));
|
|
WARN_ON(pmd_write(pmd_wrprotect(pmd_mkwrite(pmd))));
|
|
WARN_ON(pmd_dirty(pmd_wrprotect(pmd_mkclean(pmd))));
|
|
WARN_ON(!pmd_dirty(pmd_wrprotect(pmd_mkdirty(pmd))));
|
|
/*
|
|
* A huge page does not point to next level page table
|
|
* entry. Hence this must qualify as pmd_bad().
|
|
*/
|
|
WARN_ON(!pmd_bad(pmd_mkhuge(pmd)));
|
|
}
|
|
|
|
static void __init pmd_advanced_tests(struct pgtable_debug_args *args)
|
|
{
|
|
struct page *page;
|
|
pmd_t pmd;
|
|
unsigned long vaddr = args->vaddr;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
page = (args->pmd_pfn != ULONG_MAX) ? pfn_to_page(args->pmd_pfn) : NULL;
|
|
if (!page)
|
|
return;
|
|
|
|
/*
|
|
* flush_dcache_page() is called after set_pmd_at() to clear
|
|
* PG_arch_1 for the page on ARM64. The page flag isn't cleared
|
|
* when it's released and page allocation check will fail when
|
|
* the page is allocated again. For architectures other than ARM64,
|
|
* the unexpected overhead of cache flushing is acceptable.
|
|
*/
|
|
pr_debug("Validating PMD advanced\n");
|
|
/* Align the address wrt HPAGE_PMD_SIZE */
|
|
vaddr &= HPAGE_PMD_MASK;
|
|
|
|
pgtable_trans_huge_deposit(args->mm, args->pmdp, args->start_ptep);
|
|
|
|
pmd = pfn_pmd(args->pmd_pfn, args->page_prot);
|
|
set_pmd_at(args->mm, vaddr, args->pmdp, pmd);
|
|
flush_dcache_page(page);
|
|
pmdp_set_wrprotect(args->mm, vaddr, args->pmdp);
|
|
pmd = READ_ONCE(*args->pmdp);
|
|
WARN_ON(pmd_write(pmd));
|
|
pmdp_huge_get_and_clear(args->mm, vaddr, args->pmdp);
|
|
pmd = READ_ONCE(*args->pmdp);
|
|
WARN_ON(!pmd_none(pmd));
|
|
|
|
pmd = pfn_pmd(args->pmd_pfn, args->page_prot);
|
|
pmd = pmd_wrprotect(pmd);
|
|
pmd = pmd_mkclean(pmd);
|
|
set_pmd_at(args->mm, vaddr, args->pmdp, pmd);
|
|
flush_dcache_page(page);
|
|
pmd = pmd_mkwrite(pmd);
|
|
pmd = pmd_mkdirty(pmd);
|
|
pmdp_set_access_flags(args->vma, vaddr, args->pmdp, pmd, 1);
|
|
pmd = READ_ONCE(*args->pmdp);
|
|
WARN_ON(!(pmd_write(pmd) && pmd_dirty(pmd)));
|
|
pmdp_huge_get_and_clear_full(args->vma, vaddr, args->pmdp, 1);
|
|
pmd = READ_ONCE(*args->pmdp);
|
|
WARN_ON(!pmd_none(pmd));
|
|
|
|
pmd = pmd_mkhuge(pfn_pmd(args->pmd_pfn, args->page_prot));
|
|
pmd = pmd_mkyoung(pmd);
|
|
set_pmd_at(args->mm, vaddr, args->pmdp, pmd);
|
|
flush_dcache_page(page);
|
|
pmdp_test_and_clear_young(args->vma, vaddr, args->pmdp);
|
|
pmd = READ_ONCE(*args->pmdp);
|
|
WARN_ON(pmd_young(pmd));
|
|
|
|
/* Clear the pte entries */
|
|
pmdp_huge_get_and_clear(args->mm, vaddr, args->pmdp);
|
|
pgtable_trans_huge_withdraw(args->mm, args->pmdp);
|
|
}
|
|
|
|
static void __init pmd_leaf_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PMD leaf\n");
|
|
pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot);
|
|
|
|
/*
|
|
* PMD based THP is a leaf entry.
|
|
*/
|
|
pmd = pmd_mkhuge(pmd);
|
|
WARN_ON(!pmd_leaf(pmd));
|
|
}
|
|
|
|
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
|
|
static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx)
|
|
{
|
|
pgprot_t prot = vm_get_page_prot(idx);
|
|
unsigned long val = idx, *ptr = &val;
|
|
pud_t pud;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PUD basic (%pGv)\n", ptr);
|
|
pud = pfn_pud(args->fixed_pud_pfn, prot);
|
|
|
|
/*
|
|
* This test needs to be executed after the given page table entry
|
|
* is created with pfn_pud() to make sure that vm_get_page_prot(idx)
|
|
* does not have the dirty bit enabled from the beginning. This is
|
|
* important for platforms like arm64 where (!PTE_RDONLY) indicate
|
|
* dirty bit being set.
|
|
*/
|
|
WARN_ON(pud_dirty(pud_wrprotect(pud)));
|
|
|
|
WARN_ON(!pud_same(pud, pud));
|
|
WARN_ON(!pud_young(pud_mkyoung(pud_mkold(pud))));
|
|
WARN_ON(!pud_dirty(pud_mkdirty(pud_mkclean(pud))));
|
|
WARN_ON(pud_dirty(pud_mkclean(pud_mkdirty(pud))));
|
|
WARN_ON(!pud_write(pud_mkwrite(pud_wrprotect(pud))));
|
|
WARN_ON(pud_write(pud_wrprotect(pud_mkwrite(pud))));
|
|
WARN_ON(pud_young(pud_mkold(pud_mkyoung(pud))));
|
|
WARN_ON(pud_dirty(pud_wrprotect(pud_mkclean(pud))));
|
|
WARN_ON(!pud_dirty(pud_wrprotect(pud_mkdirty(pud))));
|
|
|
|
if (mm_pmd_folded(args->mm))
|
|
return;
|
|
|
|
/*
|
|
* A huge page does not point to next level page table
|
|
* entry. Hence this must qualify as pud_bad().
|
|
*/
|
|
WARN_ON(!pud_bad(pud_mkhuge(pud)));
|
|
}
|
|
|
|
static void __init pud_advanced_tests(struct pgtable_debug_args *args)
|
|
{
|
|
struct page *page;
|
|
unsigned long vaddr = args->vaddr;
|
|
pud_t pud;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
page = (args->pud_pfn != ULONG_MAX) ? pfn_to_page(args->pud_pfn) : NULL;
|
|
if (!page)
|
|
return;
|
|
|
|
/*
|
|
* flush_dcache_page() is called after set_pud_at() to clear
|
|
* PG_arch_1 for the page on ARM64. The page flag isn't cleared
|
|
* when it's released and page allocation check will fail when
|
|
* the page is allocated again. For architectures other than ARM64,
|
|
* the unexpected overhead of cache flushing is acceptable.
|
|
*/
|
|
pr_debug("Validating PUD advanced\n");
|
|
/* Align the address wrt HPAGE_PUD_SIZE */
|
|
vaddr &= HPAGE_PUD_MASK;
|
|
|
|
pud = pfn_pud(args->pud_pfn, args->page_prot);
|
|
set_pud_at(args->mm, vaddr, args->pudp, pud);
|
|
flush_dcache_page(page);
|
|
pudp_set_wrprotect(args->mm, vaddr, args->pudp);
|
|
pud = READ_ONCE(*args->pudp);
|
|
WARN_ON(pud_write(pud));
|
|
|
|
#ifndef __PAGETABLE_PMD_FOLDED
|
|
pudp_huge_get_and_clear(args->mm, vaddr, args->pudp);
|
|
pud = READ_ONCE(*args->pudp);
|
|
WARN_ON(!pud_none(pud));
|
|
#endif /* __PAGETABLE_PMD_FOLDED */
|
|
pud = pfn_pud(args->pud_pfn, args->page_prot);
|
|
pud = pud_wrprotect(pud);
|
|
pud = pud_mkclean(pud);
|
|
set_pud_at(args->mm, vaddr, args->pudp, pud);
|
|
flush_dcache_page(page);
|
|
pud = pud_mkwrite(pud);
|
|
pud = pud_mkdirty(pud);
|
|
pudp_set_access_flags(args->vma, vaddr, args->pudp, pud, 1);
|
|
pud = READ_ONCE(*args->pudp);
|
|
WARN_ON(!(pud_write(pud) && pud_dirty(pud)));
|
|
|
|
#ifndef __PAGETABLE_PMD_FOLDED
|
|
pudp_huge_get_and_clear_full(args->mm, vaddr, args->pudp, 1);
|
|
pud = READ_ONCE(*args->pudp);
|
|
WARN_ON(!pud_none(pud));
|
|
#endif /* __PAGETABLE_PMD_FOLDED */
|
|
|
|
pud = pfn_pud(args->pud_pfn, args->page_prot);
|
|
pud = pud_mkyoung(pud);
|
|
set_pud_at(args->mm, vaddr, args->pudp, pud);
|
|
flush_dcache_page(page);
|
|
pudp_test_and_clear_young(args->vma, vaddr, args->pudp);
|
|
pud = READ_ONCE(*args->pudp);
|
|
WARN_ON(pud_young(pud));
|
|
|
|
pudp_huge_get_and_clear(args->mm, vaddr, args->pudp);
|
|
}
|
|
|
|
static void __init pud_leaf_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pud_t pud;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PUD leaf\n");
|
|
pud = pfn_pud(args->fixed_pud_pfn, args->page_prot);
|
|
/*
|
|
* PUD based THP is a leaf entry.
|
|
*/
|
|
pud = pud_mkhuge(pud);
|
|
WARN_ON(!pud_leaf(pud));
|
|
}
|
|
#else /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
|
|
static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) { }
|
|
static void __init pud_advanced_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pud_leaf_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
|
|
#else /* !CONFIG_TRANSPARENT_HUGEPAGE */
|
|
static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx) { }
|
|
static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) { }
|
|
static void __init pmd_advanced_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pud_advanced_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pmd_leaf_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pud_leaf_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
|
|
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
|
|
static void __init pmd_huge_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd;
|
|
|
|
if (!arch_vmap_pmd_supported(args->page_prot) ||
|
|
args->fixed_alignment < PMD_SIZE)
|
|
return;
|
|
|
|
pr_debug("Validating PMD huge\n");
|
|
/*
|
|
* X86 defined pmd_set_huge() verifies that the given
|
|
* PMD is not a populated non-leaf entry.
|
|
*/
|
|
WRITE_ONCE(*args->pmdp, __pmd(0));
|
|
WARN_ON(!pmd_set_huge(args->pmdp, __pfn_to_phys(args->fixed_pmd_pfn), args->page_prot));
|
|
WARN_ON(!pmd_clear_huge(args->pmdp));
|
|
pmd = READ_ONCE(*args->pmdp);
|
|
WARN_ON(!pmd_none(pmd));
|
|
}
|
|
|
|
static void __init pud_huge_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pud_t pud;
|
|
|
|
if (!arch_vmap_pud_supported(args->page_prot) ||
|
|
args->fixed_alignment < PUD_SIZE)
|
|
return;
|
|
|
|
pr_debug("Validating PUD huge\n");
|
|
/*
|
|
* X86 defined pud_set_huge() verifies that the given
|
|
* PUD is not a populated non-leaf entry.
|
|
*/
|
|
WRITE_ONCE(*args->pudp, __pud(0));
|
|
WARN_ON(!pud_set_huge(args->pudp, __pfn_to_phys(args->fixed_pud_pfn), args->page_prot));
|
|
WARN_ON(!pud_clear_huge(args->pudp));
|
|
pud = READ_ONCE(*args->pudp);
|
|
WARN_ON(!pud_none(pud));
|
|
}
|
|
#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
|
|
static void __init pmd_huge_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pud_huge_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
|
|
|
|
static void __init p4d_basic_tests(struct pgtable_debug_args *args)
|
|
{
|
|
p4d_t p4d;
|
|
|
|
pr_debug("Validating P4D basic\n");
|
|
memset(&p4d, RANDOM_NZVALUE, sizeof(p4d_t));
|
|
WARN_ON(!p4d_same(p4d, p4d));
|
|
}
|
|
|
|
static void __init pgd_basic_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pgd_t pgd;
|
|
|
|
pr_debug("Validating PGD basic\n");
|
|
memset(&pgd, RANDOM_NZVALUE, sizeof(pgd_t));
|
|
WARN_ON(!pgd_same(pgd, pgd));
|
|
}
|
|
|
|
#ifndef __PAGETABLE_PUD_FOLDED
|
|
static void __init pud_clear_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pud_t pud = READ_ONCE(*args->pudp);
|
|
|
|
if (mm_pmd_folded(args->mm))
|
|
return;
|
|
|
|
pr_debug("Validating PUD clear\n");
|
|
pud = __pud(pud_val(pud) | RANDOM_ORVALUE);
|
|
WRITE_ONCE(*args->pudp, pud);
|
|
pud_clear(args->pudp);
|
|
pud = READ_ONCE(*args->pudp);
|
|
WARN_ON(!pud_none(pud));
|
|
}
|
|
|
|
static void __init pud_populate_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pud_t pud;
|
|
|
|
if (mm_pmd_folded(args->mm))
|
|
return;
|
|
|
|
pr_debug("Validating PUD populate\n");
|
|
/*
|
|
* This entry points to next level page table page.
|
|
* Hence this must not qualify as pud_bad().
|
|
*/
|
|
pud_populate(args->mm, args->pudp, args->start_pmdp);
|
|
pud = READ_ONCE(*args->pudp);
|
|
WARN_ON(pud_bad(pud));
|
|
}
|
|
#else /* !__PAGETABLE_PUD_FOLDED */
|
|
static void __init pud_clear_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pud_populate_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* PAGETABLE_PUD_FOLDED */
|
|
|
|
#ifndef __PAGETABLE_P4D_FOLDED
|
|
static void __init p4d_clear_tests(struct pgtable_debug_args *args)
|
|
{
|
|
p4d_t p4d = READ_ONCE(*args->p4dp);
|
|
|
|
if (mm_pud_folded(args->mm))
|
|
return;
|
|
|
|
pr_debug("Validating P4D clear\n");
|
|
p4d = __p4d(p4d_val(p4d) | RANDOM_ORVALUE);
|
|
WRITE_ONCE(*args->p4dp, p4d);
|
|
p4d_clear(args->p4dp);
|
|
p4d = READ_ONCE(*args->p4dp);
|
|
WARN_ON(!p4d_none(p4d));
|
|
}
|
|
|
|
static void __init p4d_populate_tests(struct pgtable_debug_args *args)
|
|
{
|
|
p4d_t p4d;
|
|
|
|
if (mm_pud_folded(args->mm))
|
|
return;
|
|
|
|
pr_debug("Validating P4D populate\n");
|
|
/*
|
|
* This entry points to next level page table page.
|
|
* Hence this must not qualify as p4d_bad().
|
|
*/
|
|
pud_clear(args->pudp);
|
|
p4d_clear(args->p4dp);
|
|
p4d_populate(args->mm, args->p4dp, args->start_pudp);
|
|
p4d = READ_ONCE(*args->p4dp);
|
|
WARN_ON(p4d_bad(p4d));
|
|
}
|
|
|
|
static void __init pgd_clear_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pgd_t pgd = READ_ONCE(*(args->pgdp));
|
|
|
|
if (mm_p4d_folded(args->mm))
|
|
return;
|
|
|
|
pr_debug("Validating PGD clear\n");
|
|
pgd = __pgd(pgd_val(pgd) | RANDOM_ORVALUE);
|
|
WRITE_ONCE(*args->pgdp, pgd);
|
|
pgd_clear(args->pgdp);
|
|
pgd = READ_ONCE(*args->pgdp);
|
|
WARN_ON(!pgd_none(pgd));
|
|
}
|
|
|
|
static void __init pgd_populate_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pgd_t pgd;
|
|
|
|
if (mm_p4d_folded(args->mm))
|
|
return;
|
|
|
|
pr_debug("Validating PGD populate\n");
|
|
/*
|
|
* This entry points to next level page table page.
|
|
* Hence this must not qualify as pgd_bad().
|
|
*/
|
|
p4d_clear(args->p4dp);
|
|
pgd_clear(args->pgdp);
|
|
pgd_populate(args->mm, args->pgdp, args->start_p4dp);
|
|
pgd = READ_ONCE(*args->pgdp);
|
|
WARN_ON(pgd_bad(pgd));
|
|
}
|
|
#else /* !__PAGETABLE_P4D_FOLDED */
|
|
static void __init p4d_clear_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pgd_clear_tests(struct pgtable_debug_args *args) { }
|
|
static void __init p4d_populate_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pgd_populate_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* PAGETABLE_P4D_FOLDED */
|
|
|
|
static void __init pte_clear_tests(struct pgtable_debug_args *args)
|
|
{
|
|
struct page *page;
|
|
pte_t pte = pfn_pte(args->pte_pfn, args->page_prot);
|
|
|
|
page = (args->pte_pfn != ULONG_MAX) ? pfn_to_page(args->pte_pfn) : NULL;
|
|
if (!page)
|
|
return;
|
|
|
|
/*
|
|
* flush_dcache_page() is called after set_pte_at() to clear
|
|
* PG_arch_1 for the page on ARM64. The page flag isn't cleared
|
|
* when it's released and page allocation check will fail when
|
|
* the page is allocated again. For architectures other than ARM64,
|
|
* the unexpected overhead of cache flushing is acceptable.
|
|
*/
|
|
pr_debug("Validating PTE clear\n");
|
|
#ifndef CONFIG_RISCV
|
|
pte = __pte(pte_val(pte) | RANDOM_ORVALUE);
|
|
#endif
|
|
set_pte_at(args->mm, args->vaddr, args->ptep, pte);
|
|
flush_dcache_page(page);
|
|
barrier();
|
|
ptep_clear(args->mm, args->vaddr, args->ptep);
|
|
pte = ptep_get(args->ptep);
|
|
WARN_ON(!pte_none(pte));
|
|
}
|
|
|
|
static void __init pmd_clear_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd = READ_ONCE(*args->pmdp);
|
|
|
|
pr_debug("Validating PMD clear\n");
|
|
pmd = __pmd(pmd_val(pmd) | RANDOM_ORVALUE);
|
|
WRITE_ONCE(*args->pmdp, pmd);
|
|
pmd_clear(args->pmdp);
|
|
pmd = READ_ONCE(*args->pmdp);
|
|
WARN_ON(!pmd_none(pmd));
|
|
}
|
|
|
|
static void __init pmd_populate_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd;
|
|
|
|
pr_debug("Validating PMD populate\n");
|
|
/*
|
|
* This entry points to next level page table page.
|
|
* Hence this must not qualify as pmd_bad().
|
|
*/
|
|
pmd_populate(args->mm, args->pmdp, args->start_ptep);
|
|
pmd = READ_ONCE(*args->pmdp);
|
|
WARN_ON(pmd_bad(pmd));
|
|
}
|
|
|
|
static void __init pte_special_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot);
|
|
|
|
if (!IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL))
|
|
return;
|
|
|
|
pr_debug("Validating PTE special\n");
|
|
WARN_ON(!pte_special(pte_mkspecial(pte)));
|
|
}
|
|
|
|
static void __init pte_protnone_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot_none);
|
|
|
|
if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
|
|
return;
|
|
|
|
pr_debug("Validating PTE protnone\n");
|
|
WARN_ON(!pte_protnone(pte));
|
|
WARN_ON(!pte_present(pte));
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static void __init pmd_protnone_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd;
|
|
|
|
if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
|
|
return;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PMD protnone\n");
|
|
pmd = pmd_mkhuge(pfn_pmd(args->fixed_pmd_pfn, args->page_prot_none));
|
|
WARN_ON(!pmd_protnone(pmd));
|
|
WARN_ON(!pmd_present(pmd));
|
|
}
|
|
#else /* !CONFIG_TRANSPARENT_HUGEPAGE */
|
|
static void __init pmd_protnone_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
|
|
#ifdef CONFIG_ARCH_HAS_PTE_DEVMAP
|
|
static void __init pte_devmap_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot);
|
|
|
|
pr_debug("Validating PTE devmap\n");
|
|
WARN_ON(!pte_devmap(pte_mkdevmap(pte)));
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static void __init pmd_devmap_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PMD devmap\n");
|
|
pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot);
|
|
WARN_ON(!pmd_devmap(pmd_mkdevmap(pmd)));
|
|
}
|
|
|
|
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
|
|
static void __init pud_devmap_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pud_t pud;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PUD devmap\n");
|
|
pud = pfn_pud(args->fixed_pud_pfn, args->page_prot);
|
|
WARN_ON(!pud_devmap(pud_mkdevmap(pud)));
|
|
}
|
|
#else /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
|
|
static void __init pud_devmap_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
|
|
#else /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
static void __init pmd_devmap_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pud_devmap_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
#else
|
|
static void __init pte_devmap_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pmd_devmap_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pud_devmap_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_ARCH_HAS_PTE_DEVMAP */
|
|
|
|
static void __init pte_soft_dirty_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot);
|
|
|
|
if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY))
|
|
return;
|
|
|
|
pr_debug("Validating PTE soft dirty\n");
|
|
WARN_ON(!pte_soft_dirty(pte_mksoft_dirty(pte)));
|
|
WARN_ON(pte_soft_dirty(pte_clear_soft_dirty(pte)));
|
|
}
|
|
|
|
static void __init pte_swap_soft_dirty_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot);
|
|
|
|
if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY))
|
|
return;
|
|
|
|
pr_debug("Validating PTE swap soft dirty\n");
|
|
WARN_ON(!pte_swp_soft_dirty(pte_swp_mksoft_dirty(pte)));
|
|
WARN_ON(pte_swp_soft_dirty(pte_swp_clear_soft_dirty(pte)));
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static void __init pmd_soft_dirty_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd;
|
|
|
|
if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY))
|
|
return;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PMD soft dirty\n");
|
|
pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot);
|
|
WARN_ON(!pmd_soft_dirty(pmd_mksoft_dirty(pmd)));
|
|
WARN_ON(pmd_soft_dirty(pmd_clear_soft_dirty(pmd)));
|
|
}
|
|
|
|
static void __init pmd_swap_soft_dirty_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd;
|
|
|
|
if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY) ||
|
|
!IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION))
|
|
return;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PMD swap soft dirty\n");
|
|
pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot);
|
|
WARN_ON(!pmd_swp_soft_dirty(pmd_swp_mksoft_dirty(pmd)));
|
|
WARN_ON(pmd_swp_soft_dirty(pmd_swp_clear_soft_dirty(pmd)));
|
|
}
|
|
#else /* !CONFIG_TRANSPARENT_HUGEPAGE */
|
|
static void __init pmd_soft_dirty_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pmd_swap_soft_dirty_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
|
|
static void __init pte_swap_exclusive_tests(struct pgtable_debug_args *args)
|
|
{
|
|
#ifdef __HAVE_ARCH_PTE_SWP_EXCLUSIVE
|
|
unsigned long max_swap_offset;
|
|
swp_entry_t entry, entry2;
|
|
pte_t pte;
|
|
|
|
pr_debug("Validating PTE swap exclusive\n");
|
|
|
|
/* See generic_max_swapfile_size(): probe the maximum offset */
|
|
max_swap_offset = swp_offset(pte_to_swp_entry(swp_entry_to_pte(swp_entry(0, ~0UL))));
|
|
|
|
/* Create a swp entry with all possible bits set */
|
|
entry = swp_entry((1 << MAX_SWAPFILES_SHIFT) - 1, max_swap_offset);
|
|
|
|
pte = swp_entry_to_pte(entry);
|
|
WARN_ON(pte_swp_exclusive(pte));
|
|
WARN_ON(!is_swap_pte(pte));
|
|
entry2 = pte_to_swp_entry(pte);
|
|
WARN_ON(memcmp(&entry, &entry2, sizeof(entry)));
|
|
|
|
pte = pte_swp_mkexclusive(pte);
|
|
WARN_ON(!pte_swp_exclusive(pte));
|
|
WARN_ON(!is_swap_pte(pte));
|
|
WARN_ON(pte_swp_soft_dirty(pte));
|
|
entry2 = pte_to_swp_entry(pte);
|
|
WARN_ON(memcmp(&entry, &entry2, sizeof(entry)));
|
|
|
|
pte = pte_swp_clear_exclusive(pte);
|
|
WARN_ON(pte_swp_exclusive(pte));
|
|
WARN_ON(!is_swap_pte(pte));
|
|
entry2 = pte_to_swp_entry(pte);
|
|
WARN_ON(memcmp(&entry, &entry2, sizeof(entry)));
|
|
#endif /* __HAVE_ARCH_PTE_SWP_EXCLUSIVE */
|
|
}
|
|
|
|
static void __init pte_swap_tests(struct pgtable_debug_args *args)
|
|
{
|
|
swp_entry_t swp;
|
|
pte_t pte;
|
|
|
|
pr_debug("Validating PTE swap\n");
|
|
pte = pfn_pte(args->fixed_pte_pfn, args->page_prot);
|
|
swp = __pte_to_swp_entry(pte);
|
|
pte = __swp_entry_to_pte(swp);
|
|
WARN_ON(args->fixed_pte_pfn != pte_pfn(pte));
|
|
}
|
|
|
|
#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
|
|
static void __init pmd_swap_tests(struct pgtable_debug_args *args)
|
|
{
|
|
swp_entry_t swp;
|
|
pmd_t pmd;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PMD swap\n");
|
|
pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot);
|
|
swp = __pmd_to_swp_entry(pmd);
|
|
pmd = __swp_entry_to_pmd(swp);
|
|
WARN_ON(args->fixed_pmd_pfn != pmd_pfn(pmd));
|
|
}
|
|
#else /* !CONFIG_ARCH_ENABLE_THP_MIGRATION */
|
|
static void __init pmd_swap_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
|
|
|
|
static void __init swap_migration_tests(struct pgtable_debug_args *args)
|
|
{
|
|
struct page *page;
|
|
swp_entry_t swp;
|
|
|
|
if (!IS_ENABLED(CONFIG_MIGRATION))
|
|
return;
|
|
|
|
/*
|
|
* swap_migration_tests() requires a dedicated page as it needs to
|
|
* be locked before creating a migration entry from it. Locking the
|
|
* page that actually maps kernel text ('start_kernel') can be real
|
|
* problematic. Lets use the allocated page explicitly for this
|
|
* purpose.
|
|
*/
|
|
page = (args->pte_pfn != ULONG_MAX) ? pfn_to_page(args->pte_pfn) : NULL;
|
|
if (!page)
|
|
return;
|
|
|
|
pr_debug("Validating swap migration\n");
|
|
|
|
/*
|
|
* make_[readable|writable]_migration_entry() expects given page to
|
|
* be locked, otherwise it stumbles upon a BUG_ON().
|
|
*/
|
|
__SetPageLocked(page);
|
|
swp = make_writable_migration_entry(page_to_pfn(page));
|
|
WARN_ON(!is_migration_entry(swp));
|
|
WARN_ON(!is_writable_migration_entry(swp));
|
|
|
|
swp = make_readable_migration_entry(swp_offset(swp));
|
|
WARN_ON(!is_migration_entry(swp));
|
|
WARN_ON(is_writable_migration_entry(swp));
|
|
|
|
swp = make_readable_migration_entry(page_to_pfn(page));
|
|
WARN_ON(!is_migration_entry(swp));
|
|
WARN_ON(is_writable_migration_entry(swp));
|
|
__ClearPageLocked(page);
|
|
}
|
|
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
static void __init hugetlb_basic_tests(struct pgtable_debug_args *args)
|
|
{
|
|
struct page *page;
|
|
pte_t pte;
|
|
|
|
pr_debug("Validating HugeTLB basic\n");
|
|
/*
|
|
* Accessing the page associated with the pfn is safe here,
|
|
* as it was previously derived from a real kernel symbol.
|
|
*/
|
|
page = pfn_to_page(args->fixed_pmd_pfn);
|
|
pte = mk_huge_pte(page, args->page_prot);
|
|
|
|
WARN_ON(!huge_pte_dirty(huge_pte_mkdirty(pte)));
|
|
WARN_ON(!huge_pte_write(huge_pte_mkwrite(huge_pte_wrprotect(pte))));
|
|
WARN_ON(huge_pte_write(huge_pte_wrprotect(huge_pte_mkwrite(pte))));
|
|
|
|
#ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB
|
|
pte = pfn_pte(args->fixed_pmd_pfn, args->page_prot);
|
|
|
|
WARN_ON(!pte_huge(pte_mkhuge(pte)));
|
|
#endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */
|
|
}
|
|
#else /* !CONFIG_HUGETLB_PAGE */
|
|
static void __init hugetlb_basic_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_HUGETLB_PAGE */
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static void __init pmd_thp_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pmd_t pmd;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PMD based THP\n");
|
|
/*
|
|
* pmd_trans_huge() and pmd_present() must return positive after
|
|
* MMU invalidation with pmd_mkinvalid(). This behavior is an
|
|
* optimization for transparent huge page. pmd_trans_huge() must
|
|
* be true if pmd_page() returns a valid THP to avoid taking the
|
|
* pmd_lock when others walk over non transhuge pmds (i.e. there
|
|
* are no THP allocated). Especially when splitting a THP and
|
|
* removing the present bit from the pmd, pmd_trans_huge() still
|
|
* needs to return true. pmd_present() should be true whenever
|
|
* pmd_trans_huge() returns true.
|
|
*/
|
|
pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot);
|
|
WARN_ON(!pmd_trans_huge(pmd_mkhuge(pmd)));
|
|
|
|
#ifndef __HAVE_ARCH_PMDP_INVALIDATE
|
|
WARN_ON(!pmd_trans_huge(pmd_mkinvalid(pmd_mkhuge(pmd))));
|
|
WARN_ON(!pmd_present(pmd_mkinvalid(pmd_mkhuge(pmd))));
|
|
#endif /* __HAVE_ARCH_PMDP_INVALIDATE */
|
|
}
|
|
|
|
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
|
|
static void __init pud_thp_tests(struct pgtable_debug_args *args)
|
|
{
|
|
pud_t pud;
|
|
|
|
if (!has_transparent_hugepage())
|
|
return;
|
|
|
|
pr_debug("Validating PUD based THP\n");
|
|
pud = pfn_pud(args->fixed_pud_pfn, args->page_prot);
|
|
WARN_ON(!pud_trans_huge(pud_mkhuge(pud)));
|
|
|
|
/*
|
|
* pud_mkinvalid() has been dropped for now. Enable back
|
|
* these tests when it comes back with a modified pud_present().
|
|
*
|
|
* WARN_ON(!pud_trans_huge(pud_mkinvalid(pud_mkhuge(pud))));
|
|
* WARN_ON(!pud_present(pud_mkinvalid(pud_mkhuge(pud))));
|
|
*/
|
|
}
|
|
#else /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
|
|
static void __init pud_thp_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
|
|
#else /* !CONFIG_TRANSPARENT_HUGEPAGE */
|
|
static void __init pmd_thp_tests(struct pgtable_debug_args *args) { }
|
|
static void __init pud_thp_tests(struct pgtable_debug_args *args) { }
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
|
|
static unsigned long __init get_random_vaddr(void)
|
|
{
|
|
unsigned long random_vaddr, random_pages, total_user_pages;
|
|
|
|
total_user_pages = (TASK_SIZE - FIRST_USER_ADDRESS) / PAGE_SIZE;
|
|
|
|
random_pages = get_random_long() % total_user_pages;
|
|
random_vaddr = FIRST_USER_ADDRESS + random_pages * PAGE_SIZE;
|
|
|
|
return random_vaddr;
|
|
}
|
|
|
|
static void __init destroy_args(struct pgtable_debug_args *args)
|
|
{
|
|
struct page *page = NULL;
|
|
|
|
/* Free (huge) page */
|
|
if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) &&
|
|
IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) &&
|
|
has_transparent_hugepage() &&
|
|
args->pud_pfn != ULONG_MAX) {
|
|
if (args->is_contiguous_page) {
|
|
free_contig_range(args->pud_pfn,
|
|
(1 << (HPAGE_PUD_SHIFT - PAGE_SHIFT)));
|
|
} else {
|
|
page = pfn_to_page(args->pud_pfn);
|
|
__free_pages(page, HPAGE_PUD_SHIFT - PAGE_SHIFT);
|
|
}
|
|
|
|
args->pud_pfn = ULONG_MAX;
|
|
args->pmd_pfn = ULONG_MAX;
|
|
args->pte_pfn = ULONG_MAX;
|
|
}
|
|
|
|
if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) &&
|
|
has_transparent_hugepage() &&
|
|
args->pmd_pfn != ULONG_MAX) {
|
|
if (args->is_contiguous_page) {
|
|
free_contig_range(args->pmd_pfn, (1 << HPAGE_PMD_ORDER));
|
|
} else {
|
|
page = pfn_to_page(args->pmd_pfn);
|
|
__free_pages(page, HPAGE_PMD_ORDER);
|
|
}
|
|
|
|
args->pmd_pfn = ULONG_MAX;
|
|
args->pte_pfn = ULONG_MAX;
|
|
}
|
|
|
|
if (args->pte_pfn != ULONG_MAX) {
|
|
page = pfn_to_page(args->pte_pfn);
|
|
__free_pages(page, 0);
|
|
|
|
args->pte_pfn = ULONG_MAX;
|
|
}
|
|
|
|
/* Free page table entries */
|
|
if (args->start_ptep) {
|
|
pte_free(args->mm, args->start_ptep);
|
|
mm_dec_nr_ptes(args->mm);
|
|
}
|
|
|
|
if (args->start_pmdp) {
|
|
pmd_free(args->mm, args->start_pmdp);
|
|
mm_dec_nr_pmds(args->mm);
|
|
}
|
|
|
|
if (args->start_pudp) {
|
|
pud_free(args->mm, args->start_pudp);
|
|
mm_dec_nr_puds(args->mm);
|
|
}
|
|
|
|
if (args->start_p4dp)
|
|
p4d_free(args->mm, args->start_p4dp);
|
|
|
|
/* Free vma and mm struct */
|
|
if (args->vma)
|
|
vm_area_free(args->vma);
|
|
|
|
if (args->mm)
|
|
mmdrop(args->mm);
|
|
}
|
|
|
|
static struct page * __init
|
|
debug_vm_pgtable_alloc_huge_page(struct pgtable_debug_args *args, int order)
|
|
{
|
|
struct page *page = NULL;
|
|
|
|
#ifdef CONFIG_CONTIG_ALLOC
|
|
if (order >= MAX_ORDER) {
|
|
page = alloc_contig_pages((1 << order), GFP_KERNEL,
|
|
first_online_node, NULL);
|
|
if (page) {
|
|
args->is_contiguous_page = true;
|
|
return page;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (order < MAX_ORDER)
|
|
page = alloc_pages(GFP_KERNEL, order);
|
|
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* Check if a physical memory range described by <pstart, pend> contains
|
|
* an area that is of size psize, and aligned to psize.
|
|
*
|
|
* Don't use address 0, an all-zeroes physical address might mask bugs, and
|
|
* it's not used on x86.
|
|
*/
|
|
static void __init phys_align_check(phys_addr_t pstart,
|
|
phys_addr_t pend, unsigned long psize,
|
|
phys_addr_t *physp, unsigned long *alignp)
|
|
{
|
|
phys_addr_t aligned_start, aligned_end;
|
|
|
|
if (pstart == 0)
|
|
pstart = PAGE_SIZE;
|
|
|
|
aligned_start = ALIGN(pstart, psize);
|
|
aligned_end = aligned_start + psize;
|
|
|
|
if (aligned_end > aligned_start && aligned_end <= pend) {
|
|
*alignp = psize;
|
|
*physp = aligned_start;
|
|
}
|
|
}
|
|
|
|
static void __init init_fixed_pfns(struct pgtable_debug_args *args)
|
|
{
|
|
u64 idx;
|
|
phys_addr_t phys, pstart, pend;
|
|
|
|
/*
|
|
* Initialize the fixed pfns. To do this, try to find a
|
|
* valid physical range, preferably aligned to PUD_SIZE,
|
|
* but settling for aligned to PMD_SIZE as a fallback. If
|
|
* neither of those is found, use the physical address of
|
|
* the start_kernel symbol.
|
|
*
|
|
* The memory doesn't need to be allocated, it just needs to exist
|
|
* as usable memory. It won't be touched.
|
|
*
|
|
* The alignment is recorded, and can be checked to see if we
|
|
* can run the tests that require an actual valid physical
|
|
* address range on some architectures ({pmd,pud}_huge_test
|
|
* on x86).
|
|
*/
|
|
|
|
phys = __pa_symbol(&start_kernel);
|
|
args->fixed_alignment = PAGE_SIZE;
|
|
|
|
for_each_mem_range(idx, &pstart, &pend) {
|
|
/* First check for a PUD-aligned area */
|
|
phys_align_check(pstart, pend, PUD_SIZE, &phys,
|
|
&args->fixed_alignment);
|
|
|
|
/* If a PUD-aligned area is found, we're done */
|
|
if (args->fixed_alignment == PUD_SIZE)
|
|
break;
|
|
|
|
/*
|
|
* If no PMD-aligned area found yet, check for one,
|
|
* but continue the loop to look for a PUD-aligned area.
|
|
*/
|
|
if (args->fixed_alignment < PMD_SIZE)
|
|
phys_align_check(pstart, pend, PMD_SIZE, &phys,
|
|
&args->fixed_alignment);
|
|
}
|
|
|
|
args->fixed_pgd_pfn = __phys_to_pfn(phys & PGDIR_MASK);
|
|
args->fixed_p4d_pfn = __phys_to_pfn(phys & P4D_MASK);
|
|
args->fixed_pud_pfn = __phys_to_pfn(phys & PUD_MASK);
|
|
args->fixed_pmd_pfn = __phys_to_pfn(phys & PMD_MASK);
|
|
args->fixed_pte_pfn = __phys_to_pfn(phys & PAGE_MASK);
|
|
WARN_ON(!pfn_valid(args->fixed_pte_pfn));
|
|
}
|
|
|
|
|
|
static int __init init_args(struct pgtable_debug_args *args)
|
|
{
|
|
struct page *page = NULL;
|
|
int ret = 0;
|
|
|
|
/*
|
|
* Initialize the debugging data.
|
|
*
|
|
* vm_get_page_prot(VM_NONE) or vm_get_page_prot(VM_SHARED|VM_NONE)
|
|
* will help create page table entries with PROT_NONE permission as
|
|
* required for pxx_protnone_tests().
|
|
*/
|
|
memset(args, 0, sizeof(*args));
|
|
args->vaddr = get_random_vaddr();
|
|
args->page_prot = vm_get_page_prot(VM_ACCESS_FLAGS);
|
|
args->page_prot_none = vm_get_page_prot(VM_NONE);
|
|
args->is_contiguous_page = false;
|
|
args->pud_pfn = ULONG_MAX;
|
|
args->pmd_pfn = ULONG_MAX;
|
|
args->pte_pfn = ULONG_MAX;
|
|
args->fixed_pgd_pfn = ULONG_MAX;
|
|
args->fixed_p4d_pfn = ULONG_MAX;
|
|
args->fixed_pud_pfn = ULONG_MAX;
|
|
args->fixed_pmd_pfn = ULONG_MAX;
|
|
args->fixed_pte_pfn = ULONG_MAX;
|
|
|
|
/* Allocate mm and vma */
|
|
args->mm = mm_alloc();
|
|
if (!args->mm) {
|
|
pr_err("Failed to allocate mm struct\n");
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
|
|
args->vma = vm_area_alloc(args->mm);
|
|
if (!args->vma) {
|
|
pr_err("Failed to allocate vma\n");
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
|
|
/*
|
|
* Allocate page table entries. They will be modified in the tests.
|
|
* Lets save the page table entries so that they can be released
|
|
* when the tests are completed.
|
|
*/
|
|
args->pgdp = pgd_offset(args->mm, args->vaddr);
|
|
args->p4dp = p4d_alloc(args->mm, args->pgdp, args->vaddr);
|
|
if (!args->p4dp) {
|
|
pr_err("Failed to allocate p4d entries\n");
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
args->start_p4dp = p4d_offset(args->pgdp, 0UL);
|
|
WARN_ON(!args->start_p4dp);
|
|
|
|
args->pudp = pud_alloc(args->mm, args->p4dp, args->vaddr);
|
|
if (!args->pudp) {
|
|
pr_err("Failed to allocate pud entries\n");
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
args->start_pudp = pud_offset(args->p4dp, 0UL);
|
|
WARN_ON(!args->start_pudp);
|
|
|
|
args->pmdp = pmd_alloc(args->mm, args->pudp, args->vaddr);
|
|
if (!args->pmdp) {
|
|
pr_err("Failed to allocate pmd entries\n");
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
args->start_pmdp = pmd_offset(args->pudp, 0UL);
|
|
WARN_ON(!args->start_pmdp);
|
|
|
|
if (pte_alloc(args->mm, args->pmdp)) {
|
|
pr_err("Failed to allocate pte entries\n");
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
args->start_ptep = pmd_pgtable(READ_ONCE(*args->pmdp));
|
|
WARN_ON(!args->start_ptep);
|
|
|
|
init_fixed_pfns(args);
|
|
|
|
/*
|
|
* Allocate (huge) pages because some of the tests need to access
|
|
* the data in the pages. The corresponding tests will be skipped
|
|
* if we fail to allocate (huge) pages.
|
|
*/
|
|
if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) &&
|
|
IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) &&
|
|
has_transparent_hugepage()) {
|
|
page = debug_vm_pgtable_alloc_huge_page(args,
|
|
HPAGE_PUD_SHIFT - PAGE_SHIFT);
|
|
if (page) {
|
|
args->pud_pfn = page_to_pfn(page);
|
|
args->pmd_pfn = args->pud_pfn;
|
|
args->pte_pfn = args->pud_pfn;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) &&
|
|
has_transparent_hugepage()) {
|
|
page = debug_vm_pgtable_alloc_huge_page(args, HPAGE_PMD_ORDER);
|
|
if (page) {
|
|
args->pmd_pfn = page_to_pfn(page);
|
|
args->pte_pfn = args->pmd_pfn;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
page = alloc_pages(GFP_KERNEL, 0);
|
|
if (page)
|
|
args->pte_pfn = page_to_pfn(page);
|
|
|
|
return 0;
|
|
|
|
error:
|
|
destroy_args(args);
|
|
return ret;
|
|
}
|
|
|
|
static int __init debug_vm_pgtable(void)
|
|
{
|
|
struct pgtable_debug_args args;
|
|
spinlock_t *ptl = NULL;
|
|
int idx, ret;
|
|
|
|
pr_info("Validating architecture page table helpers\n");
|
|
ret = init_args(&args);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/*
|
|
* Iterate over each possible vm_flags to make sure that all
|
|
* the basic page table transformation validations just hold
|
|
* true irrespective of the starting protection value for a
|
|
* given page table entry.
|
|
*
|
|
* Protection based vm_flags combinatins are always linear
|
|
* and increasing i.e starting from VM_NONE and going upto
|
|
* (VM_SHARED | READ | WRITE | EXEC).
|
|
*/
|
|
#define VM_FLAGS_START (VM_NONE)
|
|
#define VM_FLAGS_END (VM_SHARED | VM_EXEC | VM_WRITE | VM_READ)
|
|
|
|
for (idx = VM_FLAGS_START; idx <= VM_FLAGS_END; idx++) {
|
|
pte_basic_tests(&args, idx);
|
|
pmd_basic_tests(&args, idx);
|
|
pud_basic_tests(&args, idx);
|
|
}
|
|
|
|
/*
|
|
* Both P4D and PGD level tests are very basic which do not
|
|
* involve creating page table entries from the protection
|
|
* value and the given pfn. Hence just keep them out from
|
|
* the above iteration for now to save some test execution
|
|
* time.
|
|
*/
|
|
p4d_basic_tests(&args);
|
|
pgd_basic_tests(&args);
|
|
|
|
pmd_leaf_tests(&args);
|
|
pud_leaf_tests(&args);
|
|
|
|
pte_special_tests(&args);
|
|
pte_protnone_tests(&args);
|
|
pmd_protnone_tests(&args);
|
|
|
|
pte_devmap_tests(&args);
|
|
pmd_devmap_tests(&args);
|
|
pud_devmap_tests(&args);
|
|
|
|
pte_soft_dirty_tests(&args);
|
|
pmd_soft_dirty_tests(&args);
|
|
pte_swap_soft_dirty_tests(&args);
|
|
pmd_swap_soft_dirty_tests(&args);
|
|
|
|
pte_swap_exclusive_tests(&args);
|
|
|
|
pte_swap_tests(&args);
|
|
pmd_swap_tests(&args);
|
|
|
|
swap_migration_tests(&args);
|
|
|
|
pmd_thp_tests(&args);
|
|
pud_thp_tests(&args);
|
|
|
|
hugetlb_basic_tests(&args);
|
|
|
|
/*
|
|
* Page table modifying tests. They need to hold
|
|
* proper page table lock.
|
|
*/
|
|
|
|
args.ptep = pte_offset_map_lock(args.mm, args.pmdp, args.vaddr, &ptl);
|
|
pte_clear_tests(&args);
|
|
pte_advanced_tests(&args);
|
|
pte_unmap_unlock(args.ptep, ptl);
|
|
|
|
ptl = pmd_lock(args.mm, args.pmdp);
|
|
pmd_clear_tests(&args);
|
|
pmd_advanced_tests(&args);
|
|
pmd_huge_tests(&args);
|
|
pmd_populate_tests(&args);
|
|
spin_unlock(ptl);
|
|
|
|
ptl = pud_lock(args.mm, args.pudp);
|
|
pud_clear_tests(&args);
|
|
pud_advanced_tests(&args);
|
|
pud_huge_tests(&args);
|
|
pud_populate_tests(&args);
|
|
spin_unlock(ptl);
|
|
|
|
spin_lock(&(args.mm->page_table_lock));
|
|
p4d_clear_tests(&args);
|
|
pgd_clear_tests(&args);
|
|
p4d_populate_tests(&args);
|
|
pgd_populate_tests(&args);
|
|
spin_unlock(&(args.mm->page_table_lock));
|
|
|
|
destroy_args(&args);
|
|
return 0;
|
|
}
|
|
late_initcall(debug_vm_pgtable);
|