This is a note to let you know that I've just added the patch titled
mm: remove kern_addr_valid() completely
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-remove-kern_addr_valid-completely.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 42d99b3517073683091dce06d2ab83cd622cc812
Author: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Date: Tue Oct 18 15:40:14 2022 +0800
mm: remove kern_addr_valid() completely
[ Upstream commit e025ab842ec35225b1a8e163d1f311beb9e38ce9 ]
Most architectures (except arm64/x86/sparc) simply return 1 for
kern_addr_valid(), which is only used in read_kcore(), and it calls
copy_from_kernel_nofault() which could check whether the address is a
valid kernel address. So as there is no need for kern_addr_valid(), let's
remove it.
Link: https://lkml.kernel.org/r/20221018074014.185687-1-wangkefeng.wang@xxxxxxxxxx
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Acked-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> [m68k]
Acked-by: Heiko Carstens <hca@xxxxxxxxxxxxx> [s390]
Acked-by: Christoph Hellwig <hch@xxxxxx>
Acked-by: Helge Deller <deller@xxxxxx> [parisc]
Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> [powerpc]
Acked-by: Guo Ren <guoren@xxxxxxxxxx> [csky]
Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> [arm64]
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Anton Ivanov <anton.ivanov@xxxxxxxxxxxxxxxxxx>
Cc: <aou@xxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Chris Zankel <chris@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Dinh Nguyen <dinguyen@xxxxxxxxxx>
Cc: Greg Ungerer <gerg@xxxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Ivan Kokshaysky <ink@xxxxxxxxxxxxxxxxxxxx>
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
Cc: Jonas Bonn <jonas@xxxxxxxxxxxx>
Cc: Matt Turner <mattst88@xxxxxxxxx>
Cc: Max Filippov <jcmvbkbc@xxxxxxxxx>
Cc: Michal Simek <monstr@xxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Richard Henderson <richard.henderson@xxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Stafford Horne <shorne@xxxxxxxxx>
Cc: Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx>
Cc: Sven Schnelle <svens@xxxxxxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Vineet Gupta <vgupta@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Xuerui Wang <kernel@xxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Stable-dep-of: 3d5854d75e31 ("fs/proc/kcore.c: allow translation of physical memory addresses")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/alpha/include/asm/pgtable.h b/arch/alpha/include/asm/pgtable.h
index 3ea9661c09ffc..9e45f6735d5d2 100644
--- a/arch/alpha/include/asm/pgtable.h
+++ b/arch/alpha/include/asm/pgtable.h
@@ -313,8 +313,6 @@ extern inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
-#define kern_addr_valid(addr) (1)
-
#define pte_ERROR(e) \
printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
#define pmd_ERROR(e) \
diff --git a/arch/arc/include/asm/pgtable-bits-arcv2.h b/arch/arc/include/asm/pgtable-bits-arcv2.h
index b23be557403e3..515e82db519fe 100644
--- a/arch/arc/include/asm/pgtable-bits-arcv2.h
+++ b/arch/arc/include/asm/pgtable-bits-arcv2.h
@@ -120,8 +120,6 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
-#define kern_addr_valid(addr) (1)
-
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
#include <asm/hugepage.h>
#endif
diff --git a/arch/arm/include/asm/pgtable-nommu.h b/arch/arm/include/asm/pgtable-nommu.h
index 090011394477f..61480d096054d 100644
--- a/arch/arm/include/asm/pgtable-nommu.h
+++ b/arch/arm/include/asm/pgtable-nommu.h
@@ -21,8 +21,6 @@
#define pgd_none(pgd) (0)
#define pgd_bad(pgd) (0)
#define pgd_clear(pgdp)
-#define kern_addr_valid(addr) (1)
-/* FIXME */
/*
* PMD_SHIFT determines the size of the area a second-level page table can map
* PGDIR_SHIFT determines what a third-level page table entry can map
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index ef48a55e9af83..f049072b2e858 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -300,10 +300,6 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
*/
#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
-/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
-/* FIXME: this is not correct */
-#define kern_addr_valid(addr) (1)
-
/*
* We provide our own arch_get_unmapped_area to cope with VIPT caches.
*/
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 56c7df4c65325..1d713cfb0af16 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -1027,8 +1027,6 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
*/
#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
-extern int kern_addr_valid(unsigned long addr);
-
#ifdef CONFIG_ARM64_MTE
#define __HAVE_ARCH_PREPARE_TO_SWAP
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 4b302dbf78e96..6a4f118fb25f4 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -875,53 +875,6 @@ void __init paging_init(void)
create_idmap();
}
-/*
- * Check whether a kernel address is valid (derived from arch/x86/).
- */
-int kern_addr_valid(unsigned long addr)
-{
- pgd_t *pgdp;
- p4d_t *p4dp;
- pud_t *pudp, pud;
- pmd_t *pmdp, pmd;
- pte_t *ptep, pte;
-
- addr = arch_kasan_reset_tag(addr);
- if ((((long)addr) >> VA_BITS) != -1UL)
- return 0;
-
- pgdp = pgd_offset_k(addr);
- if (pgd_none(READ_ONCE(*pgdp)))
- return 0;
-
- p4dp = p4d_offset(pgdp, addr);
- if (p4d_none(READ_ONCE(*p4dp)))
- return 0;
-
- pudp = pud_offset(p4dp, addr);
- pud = READ_ONCE(*pudp);
- if (pud_none(pud))
- return 0;
-
- if (pud_sect(pud))
- return pfn_valid(pud_pfn(pud));
-
- pmdp = pmd_offset(pudp, addr);
- pmd = READ_ONCE(*pmdp);
- if (pmd_none(pmd))
- return 0;
-
- if (pmd_sect(pmd))
- return pfn_valid(pmd_pfn(pmd));
-
- ptep = pte_offset_kernel(pmdp, addr);
- pte = READ_ONCE(*ptep);
- if (pte_none(pte))
- return 0;
-
- return pfn_valid(pte_pfn(pte));
-}
-
#ifdef CONFIG_MEMORY_HOTPLUG
static void free_hotplug_page_range(struct page *page, size_t size,
struct vmem_altmap *altmap)
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index 425b398f8d456..0a62f458c5cb0 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -204,8 +204,7 @@ void __kernel_map_pages(struct page *page, int numpages, int enable)
/*
* 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
- * on kern_addr_valid(), which almost does what we need.
+ * not-valid. Walk the page table and check the PTE_VALID bit.
*
* Because this is only called on the kernel linear map, p?d_sect() implies
* p?d_present(). When debug_pagealloc is enabled, sections mappings are
diff --git a/arch/csky/include/asm/pgtable.h b/arch/csky/include/asm/pgtable.h
index c3d9b92cbe61c..77bc6caff2d23 100644
--- a/arch/csky/include/asm/pgtable.h
+++ b/arch/csky/include/asm/pgtable.h
@@ -249,9 +249,6 @@ extern void paging_init(void);
void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
pte_t *pte);
-/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
-#define kern_addr_valid(addr) (1)
-
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)
diff --git a/arch/hexagon/include/asm/page.h b/arch/hexagon/include/asm/page.h
index 7cbf719c578ec..d7d4f9fca3279 100644
--- a/arch/hexagon/include/asm/page.h
+++ b/arch/hexagon/include/asm/page.h
@@ -131,13 +131,6 @@ static inline void clear_page(void *page)
#define page_to_virt(page) __va(page_to_phys(page))
-/*
- * For port to Hexagon Virtual Machine, MAYBE we check for attempts
- * to reference reserved HVM space, but in any case, the VM will be
- * protected.
- */
-#define kern_addr_valid(addr) (1)
-
#include <asm/mem-layout.h>
#include <asm-generic/memory_model.h>
/* XXX Todo: implement assembly-optimized version of getorder. */
diff --git a/arch/ia64/include/asm/pgtable.h b/arch/ia64/include/asm/pgtable.h
index 6925e28ae61d1..01517a5e67789 100644
--- a/arch/ia64/include/asm/pgtable.h
+++ b/arch/ia64/include/asm/pgtable.h
@@ -181,22 +181,6 @@ ia64_phys_addr_valid (unsigned long addr)
return (addr & (local_cpu_data->unimpl_pa_mask)) == 0;
}
-/*
- * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
- * memory. For the return value to be meaningful, ADDR must be >=
- * PAGE_OFFSET. This operation can be relatively expensive (e.g.,
- * require a hash-, or multi-level tree-lookup or something of that
- * sort) but it guarantees to return TRUE only if accessing the page
- * at that address does not cause an error. Note that there may be
- * addresses for which kern_addr_valid() returns FALSE even though an
- * access would not cause an error (e.g., this is typically true for
- * memory mapped I/O regions.
- *
- * XXX Need to implement this for IA-64.
- */
-#define kern_addr_valid(addr) (1)
-
-
/*
* Now come the defines and routines to manage and access the three-level
* page table.
diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
index f991e678ca4b7..103df0eb8642a 100644
--- a/arch/loongarch/include/asm/pgtable.h
+++ b/arch/loongarch/include/asm/pgtable.h
@@ -425,8 +425,6 @@ static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
__update_tlb(vma, address, (pte_t *)pmdp);
}
-#define kern_addr_valid(addr) (1)
-
static inline unsigned long pmd_pfn(pmd_t pmd)
{
return (pmd_val(pmd) & _PFN_MASK) >> _PFN_SHIFT;
diff --git a/arch/m68k/include/asm/pgtable_mm.h b/arch/m68k/include/asm/pgtable_mm.h
index 9b4e2fe2ac821..b93c41fe20678 100644
--- a/arch/m68k/include/asm/pgtable_mm.h
+++ b/arch/m68k/include/asm/pgtable_mm.h
@@ -145,8 +145,6 @@ static inline void update_mmu_cache(struct vm_area_struct *vma,
#endif /* !__ASSEMBLY__ */
-#define kern_addr_valid(addr) (1)
-
/* MMU-specific headers */
#ifdef CONFIG_SUN3
diff --git a/arch/m68k/include/asm/pgtable_no.h b/arch/m68k/include/asm/pgtable_no.h
index bce5ca56c3883..fed58da3a6b65 100644
--- a/arch/m68k/include/asm/pgtable_no.h
+++ b/arch/m68k/include/asm/pgtable_no.h
@@ -20,7 +20,6 @@
#define pgd_none(pgd) (0)
#define pgd_bad(pgd) (0)
#define pgd_clear(pgdp)
-#define kern_addr_valid(addr) (1)
#define pmd_offset(a, b) ((void *)0)
#define PAGE_NONE __pgprot(0)
diff --git a/arch/microblaze/include/asm/pgtable.h b/arch/microblaze/include/asm/pgtable.h
index ba348e997dbb4..42f5988e998b8 100644
--- a/arch/microblaze/include/asm/pgtable.h
+++ b/arch/microblaze/include/asm/pgtable.h
@@ -416,9 +416,6 @@ extern unsigned long iopa(unsigned long addr);
#define IOMAP_NOCACHE_NONSER 2
#define IOMAP_NO_COPYBACK 3
-/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
-#define kern_addr_valid(addr) (1)
-
void do_page_fault(struct pt_regs *regs, unsigned long address,
unsigned long error_code);
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 4678627673dfe..a68c0b01d8cdc 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -550,8 +550,6 @@ static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
__update_tlb(vma, address, pte);
}
-#define kern_addr_valid(addr) (1)
-
/*
* Allow physical addresses to be fixed up to help 36-bit peripherals.
*/
diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
index b3d45e815295f..ab793bc517f5c 100644
--- a/arch/nios2/include/asm/pgtable.h
+++ b/arch/nios2/include/asm/pgtable.h
@@ -249,8 +249,6 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
#define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
-#define kern_addr_valid(addr) (1)
-
extern void __init paging_init(void);
extern void __init mmu_init(void);
diff --git a/arch/openrisc/include/asm/pgtable.h b/arch/openrisc/include/asm/pgtable.h
index dcae8aea132fd..6477c17b3062d 100644
--- a/arch/openrisc/include/asm/pgtable.h
+++ b/arch/openrisc/include/asm/pgtable.h
@@ -395,8 +395,6 @@ static inline void update_mmu_cache(struct vm_area_struct *vma,
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
-#define kern_addr_valid(addr) (1)
-
typedef pte_t *pte_addr_t;
#endif /* __ASSEMBLY__ */
diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h
index 68ae77069d23f..ea357430aafeb 100644
--- a/arch/parisc/include/asm/pgtable.h
+++ b/arch/parisc/include/asm/pgtable.h
@@ -23,21 +23,6 @@
#include <asm/processor.h>
#include <asm/cache.h>
-/*
- * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
- * memory. For the return value to be meaningful, ADDR must be >=
- * PAGE_OFFSET. This operation can be relatively expensive (e.g.,
- * require a hash-, or multi-level tree-lookup or something of that
- * sort) but it guarantees to return TRUE only if accessing the page
- * at that address does not cause an error. Note that there may be
- * addresses for which kern_addr_valid() returns FALSE even though an
- * access would not cause an error (e.g., this is typically true for
- * memory mapped I/O regions.
- *
- * XXX Need to implement this for parisc.
- */
-#define kern_addr_valid(addr) (1)
-
/* This is for the serialization of PxTLB broadcasts. At least on the N class
* systems, only one PxTLB inter processor broadcast can be active at any one
* time on the Merced bus. */
diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
index 283f40d05a4d7..9972626ddaf68 100644
--- a/arch/powerpc/include/asm/pgtable.h
+++ b/arch/powerpc/include/asm/pgtable.h
@@ -81,13 +81,6 @@ void poking_init(void);
extern unsigned long ioremap_bot;
extern const pgprot_t protection_map[16];
-/*
- * kern_addr_valid is intended to indicate whether an address is a valid
- * kernel address. Most 32-bit archs define it as always true (like this)
- * but most 64-bit archs actually perform a test. What should we do here?
- */
-#define kern_addr_valid(addr) (1)
-
#ifndef CONFIG_TRANSPARENT_HUGEPAGE
#define pmd_large(pmd) 0
#endif
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 2d9416a6a070e..7d1688f850c31 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -805,8 +805,6 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
#endif /* !CONFIG_MMU */
-#define kern_addr_valid(addr) (1) /* FIXME */
-
extern char _start[];
extern void *_dtb_early_va;
extern uintptr_t _dtb_early_pa;
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 956300e3568a4..4d6ab5f0a4cf0 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -1776,8 +1776,6 @@ static inline swp_entry_t __swp_entry(unsigned long type, unsigned long offset)
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
-#define kern_addr_valid(addr) (1)
-
extern int vmem_add_mapping(unsigned long start, unsigned long size);
extern void vmem_remove_mapping(unsigned long start, unsigned long size);
extern int __vmem_map_4k_page(unsigned long addr, unsigned long phys, pgprot_t prot, bool alloc);
diff --git a/arch/sh/include/asm/pgtable.h b/arch/sh/include/asm/pgtable.h
index 6fb9ec54cf9b4..3ce30becf6dfa 100644
--- a/arch/sh/include/asm/pgtable.h
+++ b/arch/sh/include/asm/pgtable.h
@@ -92,8 +92,6 @@ static inline unsigned long phys_addr_mask(void)
typedef pte_t *pte_addr_t;
-#define kern_addr_valid(addr) (1)
-
#define pte_pfn(x) ((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
struct vm_area_struct;
diff --git a/arch/sparc/include/asm/pgtable_32.h b/arch/sparc/include/asm/pgtable_32.h
index 8ff549004fac4..5acc05b572e65 100644
--- a/arch/sparc/include/asm/pgtable_32.h
+++ b/arch/sparc/include/asm/pgtable_32.h
@@ -368,12 +368,6 @@ __get_iospace (unsigned long addr)
}
}
-extern unsigned long *sparc_valid_addr_bitmap;
-
-/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
-#define kern_addr_valid(addr) \
- (test_bit(__pa((unsigned long)(addr))>>20, sparc_valid_addr_bitmap))
-
/*
* For sparc32&64, the pfn in io_remap_pfn_range() carries <iospace> in
* its high 4 bits. These macros/functions put it there or get it from there.
diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index d88e774c8eb49..9c0ea457bdf05 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -37,8 +37,7 @@
#include "mm_32.h"
-unsigned long *sparc_valid_addr_bitmap;
-EXPORT_SYMBOL(sparc_valid_addr_bitmap);
+static unsigned long *sparc_valid_addr_bitmap;
unsigned long phys_base;
EXPORT_SYMBOL(phys_base);
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index d6faee23c77dd..04f9db0c31117 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -1667,7 +1667,6 @@ bool kern_addr_valid(unsigned long addr)
return pfn_valid(pte_pfn(*pte));
}
-EXPORT_SYMBOL(kern_addr_valid);
static unsigned long __ref kernel_map_hugepud(unsigned long vstart,
unsigned long vend,
diff --git a/arch/um/include/asm/pgtable.h b/arch/um/include/asm/pgtable.h
index 66bc3f99d9bef..4e3052f2671a0 100644
--- a/arch/um/include/asm/pgtable.h
+++ b/arch/um/include/asm/pgtable.h
@@ -298,8 +298,6 @@ extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
-#define kern_addr_valid(addr) (1)
-
/* Clear a kernel PTE and flush it from the TLB */
#define kpte_clear_flush(ptep, vaddr) \
do { \
diff --git a/arch/x86/include/asm/pgtable_32.h b/arch/x86/include/asm/pgtable_32.h
index 7c9c968a42efe..7d4ad8907297c 100644
--- a/arch/x86/include/asm/pgtable_32.h
+++ b/arch/x86/include/asm/pgtable_32.h
@@ -47,15 +47,6 @@ do { \
#endif /* !__ASSEMBLY__ */
-/*
- * kern_addr_valid() is (1) for FLATMEM and (0) for SPARSEMEM
- */
-#ifdef CONFIG_FLATMEM
-#define kern_addr_valid(addr) (1)
-#else
-#define kern_addr_valid(kaddr) (0)
-#endif
-
/*
* This is used to calculate the .brk reservation for initial pagetables.
* Enough space is reserved to allocate pagetables sufficient to cover all
diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index 07cd53eeec770..a629b1b9f65a6 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -240,7 +240,6 @@ static inline void native_pgd_clear(pgd_t *pgd)
#define __swp_entry_to_pte(x) (__pte((x).val))
#define __swp_entry_to_pmd(x) (__pmd((x).val))
-extern int kern_addr_valid(unsigned long addr);
extern void cleanup_highmap(void);
#define HAVE_ARCH_UNMAPPED_AREA
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 6d294d24e488e..851711509d383 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1420,47 +1420,6 @@ void mark_rodata_ro(void)
debug_checkwx();
}
-int kern_addr_valid(unsigned long addr)
-{
- unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
- pgd_t *pgd;
- p4d_t *p4d;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
-
- if (above != 0 && above != -1UL)
- return 0;
-
- pgd = pgd_offset_k(addr);
- if (pgd_none(*pgd))
- return 0;
-
- p4d = p4d_offset(pgd, addr);
- if (!p4d_present(*p4d))
- return 0;
-
- pud = pud_offset(p4d, addr);
- if (!pud_present(*pud))
- return 0;
-
- if (pud_large(*pud))
- return pfn_valid(pud_pfn(*pud));
-
- pmd = pmd_offset(pud, addr);
- if (!pmd_present(*pmd))
- return 0;
-
- if (pmd_large(*pmd))
- return pfn_valid(pmd_pfn(*pmd));
-
- pte = pte_offset_kernel(pmd, addr);
- if (pte_none(*pte))
- return 0;
-
- return pfn_valid(pte_pfn(*pte));
-}
-
/*
* Block size is the minimum amount of memory which can be hotplugged or
* hotremoved. It must be power of two and must be equal or larger than
diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index 54f577c13afa1..5b5484d707b2e 100644
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -386,8 +386,6 @@ ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
#else
-#define kern_addr_valid(addr) (1)
-
extern void update_mmu_cache(struct vm_area_struct * vma,
unsigned long address, pte_t *ptep);
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index dff921f7ca332..590ecb79ad8b6 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -541,25 +541,17 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos)
fallthrough;
case KCORE_VMEMMAP:
case KCORE_TEXT:
- if (kern_addr_valid(start)) {
- /*
- * Using bounce buffer to bypass the
- * hardened user copy kernel text checks.
- */
- if (copy_from_kernel_nofault(buf, (void *)start,
- tsz)) {
- if (clear_user(buffer, tsz)) {
- ret = -EFAULT;
- goto out;
- }
- } else {
- if (copy_to_user(buffer, buf, tsz)) {
- ret = -EFAULT;
- goto out;
- }
+ /*
+ * Using bounce buffer to bypass the
+ * hardened user copy kernel text checks.
+ */
+ if (copy_from_kernel_nofault(buf, (void *)start, tsz)) {
+ if (clear_user(buffer, tsz)) {
+ ret = -EFAULT;
+ goto out;
}
} else {
- if (clear_user(buffer, tsz)) {
+ if (copy_to_user(buffer, buf, tsz)) {
ret = -EFAULT;
goto out;
}
