arch, mm: restore dependency of __kernel_map_pages() on DEBUG_PAGEALLOC

The design of DEBUG_PAGEALLOC presumes that __kernel_map_pages() must
never fail.  With this assumption is wouldn't be safe to allow general
usage of this function.

Moreover, some architectures that implement __kernel_map_pages() have this
function guarded by #ifdef DEBUG_PAGEALLOC and some refuse to map/unmap
pages when page allocation debugging is disabled at runtime.

As all the users of __kernel_map_pages() were converted to use
debug_pagealloc_map_pages() it is safe to make it available only when
DEBUG_PAGEALLOC is set.

Link: https://lkml.kernel.org/r/20201109192128.960-4-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mike Rapoport 2020-12-14 19:10:30 -08:00 committed by Linus Torvalds
parent 2abf962a8d
commit 5d6ad668f3
12 changed files with 26 additions and 26 deletions

View File

@ -1047,6 +1047,9 @@ config ARCH_WANT_LD_ORPHAN_WARN
config HAVE_ARCH_PFN_VALID
bool
config ARCH_SUPPORTS_DEBUG_PAGEALLOC
bool
source "kernel/gcov/Kconfig"
source "scripts/gcc-plugins/Kconfig"

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@ -71,6 +71,7 @@ config ARM64
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
select ARCH_USE_SYM_ANNOTATIONS
select ARCH_SUPPORTS_DEBUG_PAGEALLOC
select ARCH_SUPPORTS_MEMORY_FAILURE
select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
select ARCH_SUPPORTS_ATOMIC_RMW
@ -1028,9 +1029,6 @@ config HOLES_IN_ZONE
source "kernel/Kconfig.hz"
config ARCH_SUPPORTS_DEBUG_PAGEALLOC
def_bool y
config ARCH_SPARSEMEM_ENABLE
def_bool y
select SPARSEMEM_VMEMMAP_ENABLE

View File

@ -155,7 +155,7 @@ int set_direct_map_invalid_noflush(struct page *page)
.clear_mask = __pgprot(PTE_VALID),
};
if (!rodata_full)
if (!debug_pagealloc_enabled() && !rodata_full)
return 0;
return apply_to_page_range(&init_mm,
@ -170,7 +170,7 @@ int set_direct_map_default_noflush(struct page *page)
.clear_mask = __pgprot(PTE_RDONLY),
};
if (!rodata_full)
if (!debug_pagealloc_enabled() && !rodata_full)
return 0;
return apply_to_page_range(&init_mm,
@ -178,6 +178,7 @@ int set_direct_map_default_noflush(struct page *page)
PAGE_SIZE, change_page_range, &data);
}
#ifdef CONFIG_DEBUG_PAGEALLOC
void __kernel_map_pages(struct page *page, int numpages, int enable)
{
if (!debug_pagealloc_enabled() && !rodata_full)
@ -186,6 +187,7 @@ void __kernel_map_pages(struct page *page, int numpages, int enable)
set_memory_valid((unsigned long)page_address(page), numpages, enable);
}
#ifdef CONFIG_HIBERNATION
/*
* This function is used to determine if a linear map page has been marked as
* not-valid. Walk the page table and check the PTE_VALID bit. This is based
@ -232,3 +234,5 @@ bool kernel_page_present(struct page *page)
ptep = pte_offset_kernel(pmdp, addr);
return pte_valid(READ_ONCE(*ptep));
}
#endif /* CONFIG_HIBERNATION */
#endif /* CONFIG_DEBUG_PAGEALLOC */

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@ -146,6 +146,7 @@ config PPC
select ARCH_MIGHT_HAVE_PC_SERIO
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_DEBUG_PAGEALLOC if PPC32 || PPC_BOOK3S_64
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_CMPXCHG_LOCKREF if PPC64
select ARCH_USE_QUEUED_RWLOCKS if PPC_QUEUED_SPINLOCKS
@ -356,10 +357,6 @@ config PPC_OF_PLATFORM_PCI
depends on PCI
depends on PPC64 # not supported on 32 bits yet
config ARCH_SUPPORTS_DEBUG_PAGEALLOC
depends on PPC32 || PPC_BOOK3S_64
def_bool y
config ARCH_SUPPORTS_UPROBES
def_bool y

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@ -14,6 +14,7 @@ config RISCV
def_bool y
select ARCH_CLOCKSOURCE_INIT
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
select ARCH_HAS_BINFMT_FLAT
select ARCH_HAS_DEBUG_VM_PGTABLE
select ARCH_HAS_DEBUG_VIRTUAL if MMU
@ -153,9 +154,6 @@ config ARCH_SELECT_MEMORY_MODEL
config ARCH_WANT_GENERAL_HUGETLB
def_bool y
config ARCH_SUPPORTS_DEBUG_PAGEALLOC
def_bool y
config SYS_SUPPORTS_HUGETLBFS
depends on MMU
def_bool y

View File

@ -461,8 +461,6 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
#define VMALLOC_START 0
#define VMALLOC_END TASK_SIZE
static inline void __kernel_map_pages(struct page *page, int numpages, int enable) {}
#endif /* !CONFIG_MMU */
#define kern_addr_valid(addr) (1) /* FIXME */

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@ -184,6 +184,7 @@ int set_direct_map_default_noflush(struct page *page)
return ret;
}
#ifdef CONFIG_DEBUG_PAGEALLOC
void __kernel_map_pages(struct page *page, int numpages, int enable)
{
if (!debug_pagealloc_enabled())
@ -196,3 +197,4 @@ void __kernel_map_pages(struct page *page, int numpages, int enable)
__set_memory((unsigned long)page_address(page), numpages,
__pgprot(0), __pgprot(_PAGE_PRESENT));
}
#endif

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@ -35,9 +35,6 @@ config GENERIC_LOCKBREAK
config PGSTE
def_bool y if KVM
config ARCH_SUPPORTS_DEBUG_PAGEALLOC
def_bool y
config AUDIT_ARCH
def_bool y
@ -106,6 +103,7 @@ config S390
select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
select ARCH_STACKWALK
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_DEBUG_PAGEALLOC
select ARCH_SUPPORTS_NUMA_BALANCING
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_CMPXCHG_LOCKREF

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@ -88,6 +88,7 @@ config SPARC64
select HAVE_C_RECORDMCOUNT
select HAVE_ARCH_AUDITSYSCALL
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_DEBUG_PAGEALLOC
select HAVE_NMI
select HAVE_REGS_AND_STACK_ACCESS_API
select ARCH_USE_QUEUED_RWLOCKS
@ -148,9 +149,6 @@ config GENERIC_ISA_DMA
bool
default y if SPARC32
config ARCH_SUPPORTS_DEBUG_PAGEALLOC
def_bool y if SPARC64
config PGTABLE_LEVELS
default 4 if 64BIT
default 3

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@ -91,6 +91,7 @@ config X86
select ARCH_STACKWALK
select ARCH_SUPPORTS_ACPI
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_DEBUG_PAGEALLOC
select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_QUEUED_RWLOCKS
@ -331,9 +332,6 @@ config ZONE_DMA32
config AUDIT_ARCH
def_bool y if X86_64
config ARCH_SUPPORTS_DEBUG_PAGEALLOC
def_bool y
config KASAN_SHADOW_OFFSET
hex
depends on KASAN

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@ -2194,6 +2194,7 @@ int set_direct_map_default_noflush(struct page *page)
return __set_pages_p(page, 1);
}
#ifdef CONFIG_DEBUG_PAGEALLOC
void __kernel_map_pages(struct page *page, int numpages, int enable)
{
if (PageHighMem(page))
@ -2239,6 +2240,7 @@ bool kernel_page_present(struct page *page)
return (pte_val(*pte) & _PAGE_PRESENT);
}
#endif /* CONFIG_HIBERNATION */
#endif /* CONFIG_DEBUG_PAGEALLOC */
int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
unsigned numpages, unsigned long page_flags)

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@ -2931,7 +2931,11 @@ static inline bool debug_pagealloc_enabled_static(void)
return static_branch_unlikely(&_debug_pagealloc_enabled);
}
#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_ARCH_HAS_SET_DIRECT_MAP)
#ifdef CONFIG_DEBUG_PAGEALLOC
/*
* To support DEBUG_PAGEALLOC architecture must ensure that
* __kernel_map_pages() never fails
*/
extern void __kernel_map_pages(struct page *page, int numpages, int enable);
static inline void debug_pagealloc_map_pages(struct page *page, int numpages)
@ -2949,13 +2953,13 @@ static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages)
#ifdef CONFIG_HIBERNATION
extern bool kernel_page_present(struct page *page);
#endif /* CONFIG_HIBERNATION */
#else /* CONFIG_DEBUG_PAGEALLOC || CONFIG_ARCH_HAS_SET_DIRECT_MAP */
#else /* CONFIG_DEBUG_PAGEALLOC */
static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {}
static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {}
#ifdef CONFIG_HIBERNATION
static inline bool kernel_page_present(struct page *page) { return true; }
#endif /* CONFIG_HIBERNATION */
#endif /* CONFIG_DEBUG_PAGEALLOC || CONFIG_ARCH_HAS_SET_DIRECT_MAP */
#endif /* CONFIG_DEBUG_PAGEALLOC */
#ifdef __HAVE_ARCH_GATE_AREA
extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);