diff mbox series

[v7,7/7] powerpc: mm: Support page table check

Message ID 20230215020155.1969194-8-rmclure@linux.ibm.com (mailing list archive)
State Superseded
Headers show
Series Support page table check | expand

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Commit Message

Rohan McLure Feb. 15, 2023, 2:01 a.m. UTC 
On creation and clearing of a page table mapping, instrument such calls
by invoking page_table_check_pte_set and page_table_check_pte_clear
respectively. These calls serve as a sanity check against illegal
mappings.

Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK for all platforms.

Use set_pte internally, and cause this function to reassign a page table
entry without instrumentation. Generic code will be instrumented, as it
references set_pte_at.

See also:

riscv support in commit 3fee229a8eb9 ("riscv/mm: enable
ARCH_SUPPORTS_PAGE_TABLE_CHECK")
arm64 in commit 42b2547137f5 ("arm64/mm: enable
ARCH_SUPPORTS_PAGE_TABLE_CHECK")
x86_64 in commit d283d422c6c4 ("x86: mm: add x86_64 support for page table
check")

Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
---
V2: Update spacing and types assigned to pte_update calls.
V3: Update one last pte_update call to remove __pte invocation.
V5: Fix 32-bit nohash double set
V6: Omit __set_pte_at instrumentation - should be instrumented by
set_pte_at, with set_pte in between, performing all prior checks.
Instrument pmds. Use set_pte where needed.
V7: Make set_pte_at an inline function. Fix commit message.
Detail changes of internal references to set_pte_at, and its semantics.
---
 arch/powerpc/Kconfig                         |  1 +
 arch/powerpc/include/asm/book3s/32/pgtable.h |  8 +++-
 arch/powerpc/include/asm/book3s/64/pgtable.h | 44 ++++++++++++++++----
 arch/powerpc/include/asm/nohash/32/pgtable.h |  7 +++-
 arch/powerpc/include/asm/nohash/64/pgtable.h |  8 +++-
 arch/powerpc/include/asm/pgtable.h           | 10 ++++-
 arch/powerpc/mm/book3s64/hash_pgtable.c      |  2 +-
 arch/powerpc/mm/book3s64/pgtable.c           | 16 ++++---
 arch/powerpc/mm/book3s64/radix_pgtable.c     | 10 ++---
 arch/powerpc/mm/nohash/book3e_pgtable.c      |  2 +-
 arch/powerpc/mm/pgtable_32.c                 |  2 +-
 11 files changed, 83 insertions(+), 27 deletions(-)

Comments

Christophe Leroy Feb. 15, 2023, 7:19 a.m. UTC | #1 
Le 15/02/2023 à 03:01, Rohan McLure a écrit :
> On creation and clearing of a page table mapping, instrument such calls
> by invoking page_table_check_pte_set and page_table_check_pte_clear
> respectively. These calls serve as a sanity check against illegal
> mappings.
> 
> Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK for all platforms.
> 
> Use set_pte internally, and cause this function to reassign a page table
> entry without instrumentation. Generic code will be instrumented, as it
> references set_pte_at.
> 
> See also:
> 
> riscv support in commit 3fee229a8eb9 ("riscv/mm: enable
> ARCH_SUPPORTS_PAGE_TABLE_CHECK")
> arm64 in commit 42b2547137f5 ("arm64/mm: enable
> ARCH_SUPPORTS_PAGE_TABLE_CHECK")
> x86_64 in commit d283d422c6c4 ("x86: mm: add x86_64 support for page table
> check")
> 
> Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>

> ---
> V2: Update spacing and types assigned to pte_update calls.
> V3: Update one last pte_update call to remove __pte invocation.
> V5: Fix 32-bit nohash double set
> V6: Omit __set_pte_at instrumentation - should be instrumented by
> set_pte_at, with set_pte in between, performing all prior checks.
> Instrument pmds. Use set_pte where needed.
> V7: Make set_pte_at an inline function. Fix commit message.
> Detail changes of internal references to set_pte_at, and its semantics.
> ---
>   arch/powerpc/Kconfig                         |  1 +
>   arch/powerpc/include/asm/book3s/32/pgtable.h |  8 +++-
>   arch/powerpc/include/asm/book3s/64/pgtable.h | 44 ++++++++++++++++----
>   arch/powerpc/include/asm/nohash/32/pgtable.h |  7 +++-
>   arch/powerpc/include/asm/nohash/64/pgtable.h |  8 +++-
>   arch/powerpc/include/asm/pgtable.h           | 10 ++++-
>   arch/powerpc/mm/book3s64/hash_pgtable.c      |  2 +-
>   arch/powerpc/mm/book3s64/pgtable.c           | 16 ++++---
>   arch/powerpc/mm/book3s64/radix_pgtable.c     | 10 ++---
>   arch/powerpc/mm/nohash/book3e_pgtable.c      |  2 +-
>   arch/powerpc/mm/pgtable_32.c                 |  2 +-
>   11 files changed, 83 insertions(+), 27 deletions(-)
> 
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 2c9cdf1d8761..2474e2699037 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -154,6 +154,7 @@ config PPC
>   	select ARCH_STACKWALK
>   	select ARCH_SUPPORTS_ATOMIC_RMW
>   	select ARCH_SUPPORTS_DEBUG_PAGEALLOC	if PPC_BOOK3S || PPC_8xx || 40x
> +	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
>   	select ARCH_USE_BUILTIN_BSWAP
>   	select ARCH_USE_CMPXCHG_LOCKREF		if PPC64
>   	select ARCH_USE_MEMTEST
> diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
> index afd672e84791..8850b4fb22a4 100644
> --- a/arch/powerpc/include/asm/book3s/32/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
> @@ -53,6 +53,8 @@
>   
>   #ifndef __ASSEMBLY__
>   
> +#include <linux/page_table_check.h>
> +
>   static inline bool pte_user(pte_t pte)
>   {
>   	return pte_val(pte) & _PAGE_USER;
> @@ -338,7 +340,11 @@ static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
>   static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
>   				       pte_t *ptep)
>   {
> -	return __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0));
> +	pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0));
> +
> +	page_table_check_pte_clear(mm, addr, old_pte);
> +
> +	return old_pte;
>   }
>   
>   #define __HAVE_ARCH_PTEP_SET_WRPROTECT
> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
> index a6ed93d01da1..0c6838875720 100644
> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
> @@ -162,6 +162,8 @@
>   #define PAGE_KERNEL_ROX	__pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX)
>   
>   #ifndef __ASSEMBLY__
> +#include <linux/page_table_check.h>
> +
>   /*
>    * page table defines
>    */
> @@ -431,8 +433,11 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
>   static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
>   				       unsigned long addr, pte_t *ptep)
>   {
> -	unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0, 0);
> -	return __pte(old);
> +	pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0));
> +
> +	page_table_check_pte_clear(mm, addr, old_pte);
> +
> +	return old_pte;
>   }
>   
>   #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
> @@ -441,11 +446,16 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
>   					    pte_t *ptep, int full)
>   {
>   	if (full && radix_enabled()) {
> +		pte_t old_pte;
> +
>   		/*
>   		 * We know that this is a full mm pte clear and
>   		 * hence can be sure there is no parallel set_pte.
>   		 */
> -		return radix__ptep_get_and_clear_full(mm, addr, ptep, full);
> +		old_pte = radix__ptep_get_and_clear_full(mm, addr, ptep, full);
> +		page_table_check_pte_clear(mm, addr, old_pte);
> +
> +		return old_pte;
>   	}
>   	return ptep_get_and_clear(mm, addr, ptep);
>   }
> @@ -1249,17 +1259,33 @@ extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
>   static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
>   					    unsigned long addr, pmd_t *pmdp)
>   {
> -	if (radix_enabled())
> -		return radix__pmdp_huge_get_and_clear(mm, addr, pmdp);
> -	return hash__pmdp_huge_get_and_clear(mm, addr, pmdp);
> +	pmd_t old_pmd;
> +
> +	if (radix_enabled()) {
> +		old_pmd = radix__pmdp_huge_get_and_clear(mm, addr, pmdp);
> +	} else {
> +		old_pmd = hash__pmdp_huge_get_and_clear(mm, addr, pmdp);
> +	}
> +
> +	page_table_check_pmd_clear(mm, addr, old_pmd);
> +
> +	return old_pmd;
>   }
>   
>   static inline pmd_t __pmdp_collapse_flush(struct vm_area_struct *vma, struct mm_struct *mm,
>   					  unsigned long address, pmd_t *pmdp)
>   {
> -	if (radix_enabled())
> -		return radix__pmdp_collapse_flush(vma, address, pmdp);
> -	return hash__pmdp_collapse_flush(vma, address, pmdp);
> +	pmd_t old_pmd;
> +
> +	if (radix_enabled()) {
> +		old_pmd = radix__pmdp_collapse_flush(vma, address, pmdp);
> +	} else {
> +		old_pmd = hash__pmdp_collapse_flush(vma, address, pmdp);
> +	}
> +
> +	page_table_check_pmd_clear(mm, address, old_pmd);
> +
> +	return old_pmd;
>   }
>   #define pmdp_collapse_flush(__vma, __addr, __pmdp)			\
>   ({									\
> diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
> index d953533c56ff..e9c77054fe0b 100644
> --- a/arch/powerpc/include/asm/nohash/32/pgtable.h
> +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
> @@ -166,6 +166,7 @@ void unmap_kernel_page(unsigned long va);
>   #define _PAGE_CHG_MASK	(PTE_RPN_MASK | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_SPECIAL)
>   
>   #ifndef __ASSEMBLY__
> +#include <linux/page_table_check.h>
>   
>   #define pte_clear(mm, addr, ptep) \
>   	do { pte_update(mm, addr, ptep, ~0, 0, 0); } while (0)
> @@ -316,7 +317,11 @@ static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
>   static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
>   				       pte_t *ptep)
>   {
> -	return __pte(pte_update(mm, addr, ptep, ~0, 0, 0));
> +	pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0, 0, 0));
> +
> +	page_table_check_pte_clear(mm, addr, old_pte);
> +
> +	return old_pte;
>   }
>   
>   #define __HAVE_ARCH_PTEP_SET_WRPROTECT
> diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
> index 14e69ebad31f..d88b22c753d3 100644
> --- a/arch/powerpc/include/asm/nohash/64/pgtable.h
> +++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
> @@ -83,6 +83,7 @@
>   #define H_PAGE_4K_PFN 0
>   
>   #ifndef __ASSEMBLY__
> +#include <linux/page_table_check.h>
>   /* pte_clear moved to later in this file */
>   
>   static inline pte_t pte_mkwrite(pte_t pte)
> @@ -259,8 +260,11 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
>   static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
>   				       unsigned long addr, pte_t *ptep)
>   {
> -	unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0, 0);
> -	return __pte(old);
> +	pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0));
> +
> +	page_table_check_pte_clear(mm, addr, old_pte);
> +
> +	return old_pte;
>   }
>   
>   static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
> diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
> index b76fdb80b6c9..5715350e603a 100644
> --- a/arch/powerpc/include/asm/pgtable.h
> +++ b/arch/powerpc/include/asm/pgtable.h
> @@ -5,6 +5,7 @@
>   #ifndef __ASSEMBLY__
>   #include <linux/mmdebug.h>
>   #include <linux/mmzone.h>
> +#include <linux/page_table_check.h>
>   #include <asm/processor.h>		/* For TASK_SIZE */
>   #include <asm/mmu.h>
>   #include <asm/page.h>
> @@ -48,7 +49,7 @@ struct mm_struct;
>   /* Keep these as a macros to avoid include dependency mess */
>   #define pte_page(x)		pfn_to_page(pte_pfn(x))
>   #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
> -#define set_pte_at  		set_pte
> +
>   /*
>    * Select all bits except the pfn
>    */
> @@ -153,6 +154,13 @@ struct seq_file;
>   void arch_report_meminfo(struct seq_file *m);
>   #endif /* CONFIG_PPC64 */
>   
> +static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
> +			      pte_t *ptep, pte_t pte)
> +{
> +	page_table_check_pte_set(mm, addr, ptep, pte);
> +	set_pte(mm, addr, ptep, pte);
> +}
> +
>   /*
>    * Currently only consumed by page_table_check_pud_{set,clear}. Since clears
>    * and sets to page table entries at any level are done through
> diff --git a/arch/powerpc/mm/book3s64/hash_pgtable.c b/arch/powerpc/mm/book3s64/hash_pgtable.c
> index 51f48984abca..a92a8a7c9199 100644
> --- a/arch/powerpc/mm/book3s64/hash_pgtable.c
> +++ b/arch/powerpc/mm/book3s64/hash_pgtable.c
> @@ -165,7 +165,7 @@ int hash__map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
>   		ptep = pte_alloc_kernel(pmdp, ea);
>   		if (!ptep)
>   			return -ENOMEM;
> -		set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot));
> +		set_pte(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot));
>   	} else {
>   		/*
>   		 * If the mm subsystem is not fully up, we cannot create a
> diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
> index 85c84e89e3ea..d95be1d08b79 100644
> --- a/arch/powerpc/mm/book3s64/pgtable.c
> +++ b/arch/powerpc/mm/book3s64/pgtable.c
> @@ -9,6 +9,7 @@
>   #include <linux/memremap.h>
>   #include <linux/pkeys.h>
>   #include <linux/debugfs.h>
> +#include <linux/page_table_check.h>
>   #include <misc/cxl-base.h>
>   
>   #include <asm/pgalloc.h>
> @@ -87,7 +88,10 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr,
>   	WARN_ON(!(pmd_large(pmd)));
>   #endif
>   	trace_hugepage_set_pmd(addr, pmd_val(pmd));
> -	return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd));
> +
> +	page_table_check_pmd_set(mm, addr, pmdp, pmd);
> +
> +	return set_pte(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd));
>   }
>   
>   static void do_serialize(void *arg)
> @@ -122,11 +126,13 @@ void serialize_against_pte_lookup(struct mm_struct *mm)
>   pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
>   		     pmd_t *pmdp)
>   {
> -	unsigned long old_pmd;
> +	pmd_t old_pmd;
>   
> -	old_pmd = pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID);
> +	old_pmd = __pmd(pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID));
>   	flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
> -	return __pmd(old_pmd);
> +	page_table_check_pmd_clear(vma->vm_mm, address, old_pmd);
> +
> +	return old_pmd;
>   }
>   
>   pmd_t pmdp_huge_get_and_clear_full(struct vm_area_struct *vma,
> @@ -460,7 +466,7 @@ void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
>   	if (radix_enabled())
>   		return radix__ptep_modify_prot_commit(vma, addr,
>   						      ptep, old_pte, pte);
> -	set_pte_at(vma->vm_mm, addr, ptep, pte);
> +	set_pte(vma->vm_mm, addr, ptep, pte);
>   }
>   
>   /*
> diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
> index 4e46e001c3c3..9359e3589107 100644
> --- a/arch/powerpc/mm/book3s64/radix_pgtable.c
> +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
> @@ -110,7 +110,7 @@ static int early_map_kernel_page(unsigned long ea, unsigned long pa,
>   	ptep = pte_offset_kernel(pmdp, ea);
>   
>   set_the_pte:
> -	set_pte_at(&init_mm, ea, ptep, pfn_pte(pfn, flags));
> +	set_pte(&init_mm, ea, ptep, pfn_pte(pfn, flags));
>   	asm volatile("ptesync": : :"memory");
>   	return 0;
>   }
> @@ -170,7 +170,7 @@ static int __map_kernel_page(unsigned long ea, unsigned long pa,
>   		return -ENOMEM;
>   
>   set_the_pte:
> -	set_pte_at(&init_mm, ea, ptep, pfn_pte(pfn, flags));
> +	set_pte(&init_mm, ea, ptep, pfn_pte(pfn, flags));
>   	asm volatile("ptesync": : :"memory");
>   	return 0;
>   }
> @@ -1094,7 +1094,7 @@ void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
>   	    (atomic_read(&mm->context.copros) > 0))
>   		radix__flush_tlb_page(vma, addr);
>   
> -	set_pte_at(mm, addr, ptep, pte);
> +	set_pte(mm, addr, ptep, pte);
>   }
>   
>   int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
> @@ -1105,7 +1105,7 @@ int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
>   	if (!radix_enabled())
>   		return 0;
>   
> -	set_pte_at(&init_mm, 0 /* radix unused */, ptep, new_pud);
> +	set_pte(&init_mm, 0 /* radix unused */, ptep, new_pud);
>   
>   	return 1;
>   }
> @@ -1152,7 +1152,7 @@ int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
>   	if (!radix_enabled())
>   		return 0;
>   
> -	set_pte_at(&init_mm, 0 /* radix unused */, ptep, new_pmd);
> +	set_pte(&init_mm, 0 /* radix unused */, ptep, new_pmd);
>   
>   	return 1;
>   }
> diff --git a/arch/powerpc/mm/nohash/book3e_pgtable.c b/arch/powerpc/mm/nohash/book3e_pgtable.c
> index b80fc4a91a53..e50d22c6f983 100644
> --- a/arch/powerpc/mm/nohash/book3e_pgtable.c
> +++ b/arch/powerpc/mm/nohash/book3e_pgtable.c
> @@ -111,7 +111,7 @@ int __ref map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
>   		}
>   		ptep = pte_offset_kernel(pmdp, ea);
>   	}
> -	set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot));
> +	set_pte(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot));
>   
>   	smp_wmb();
>   	return 0;
> diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
> index 5c02fd08d61e..a86a16be24ea 100644
> --- a/arch/powerpc/mm/pgtable_32.c
> +++ b/arch/powerpc/mm/pgtable_32.c
> @@ -89,7 +89,7 @@ int __ref map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot)
>   		 * hash table
>   		 */
>   		BUG_ON((pte_present(*pg) | pte_hashpte(*pg)) && pgprot_val(prot));
> -		set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, prot));
> +		set_pte(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, prot));
>   	}
>   	smp_wmb();
>   	return err;
kernel test robot Feb. 15, 2023, 7:56 a.m. UTC | #2 
Hi Rohan,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on powerpc/next]
[also build test ERROR on powerpc/fixes powerpc/topic/ppc-kvm linus/master v6.2-rc8]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Rohan-McLure/powerpc-mm-Separate-set_pte-set_pte_at-for-internal-external-use/20230215-101202
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
patch link:    https://lore.kernel.org/r/20230215020155.1969194-8-rmclure%40linux.ibm.com
patch subject: [PATCH v7 7/7] powerpc: mm: Support page table check
config: powerpc-allyesconfig
compiler: powerpc-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/a8f0cdada09daa34ed60168063853d78dae94900
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Rohan-McLure/powerpc-mm-Separate-set_pte-set_pte_at-for-internal-external-use/20230215-101202
        git checkout a8f0cdada09daa34ed60168063853d78dae94900
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc prepare

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202302151512.B4jBR2PN-lkp@intel.com/

All errors (new ones prefixed by >>):

   scripts/genksyms/parse.y: warning: 9 shift/reduce conflicts [-Wconflicts-sr]
   scripts/genksyms/parse.y: warning: 5 reduce/reduce conflicts [-Wconflicts-rr]
   scripts/genksyms/parse.y: note: rerun with option '-Wcounterexamples' to generate conflict counterexamples
   In file included from arch/powerpc/include/asm/pgtable.h:8,
                    from include/linux/pgtable.h:6,
                    from arch/powerpc/include/asm/kup.h:37,
                    from arch/powerpc/include/asm/uaccess.h:8,
                    from include/linux/uaccess.h:11,
                    from include/linux/sched/task.h:11,
                    from include/linux/sched/signal.h:9,
                    from include/linux/rcuwait.h:6,
                    from include/linux/percpu-rwsem.h:7,
                    from include/linux/fs.h:33,
                    from include/linux/compat.h:17,
                    from arch/powerpc/kernel/asm-offsets.c:12:
>> include/linux/page_table_check.h:20:35: error: unknown type name 'pmd_t'; did you mean 'pgd_t'?
      20 |                                   pmd_t pmd);
         |                                   ^~~~~
         |                                   pgd_t
>> include/linux/page_table_check.h:22:35: error: unknown type name 'pud_t'; did you mean 'pgd_t'?
      22 |                                   pud_t pud);
         |                                   ^~~~~
         |                                   pgd_t
   include/linux/page_table_check.h:26:33: error: unknown type name 'pmd_t'; did you mean 'pgd_t'?
      26 |                                 pmd_t *pmdp, pmd_t pmd);
         |                                 ^~~~~
         |                                 pgd_t
   include/linux/page_table_check.h:26:46: error: unknown type name 'pmd_t'; did you mean 'pgd_t'?
      26 |                                 pmd_t *pmdp, pmd_t pmd);
         |                                              ^~~~~
         |                                              pgd_t
   include/linux/page_table_check.h:28:33: error: unknown type name 'pud_t'; did you mean 'pgd_t'?
      28 |                                 pud_t *pudp, pud_t pud);
         |                                 ^~~~~
         |                                 pgd_t
   include/linux/page_table_check.h:28:46: error: unknown type name 'pud_t'; did you mean 'pgd_t'?
      28 |                                 pud_t *pudp, pud_t pud);
         |                                              ^~~~~
         |                                              pgd_t
   include/linux/page_table_check.h:31:41: error: unknown type name 'pmd_t'; did you mean 'pgd_t'?
      31 |                                         pmd_t pmd);
         |                                         ^~~~~
         |                                         pgd_t
   include/linux/page_table_check.h:59:67: error: unknown type name 'pmd_t'; did you mean 'pgd_t'?
      59 |                                               unsigned long addr, pmd_t pmd)
         |                                                                   ^~~~~
         |                                                                   pgd_t
   include/linux/page_table_check.h:68:67: error: unknown type name 'pud_t'; did you mean 'pgd_t'?
      68 |                                               unsigned long addr, pud_t pud)
         |                                                                   ^~~~~
         |                                                                   pgd_t
   include/linux/page_table_check.h:87:65: error: unknown type name 'pmd_t'; did you mean 'pgd_t'?
      87 |                                             unsigned long addr, pmd_t *pmdp,
         |                                                                 ^~~~~
         |                                                                 pgd_t
   include/linux/page_table_check.h:88:45: error: unknown type name 'pmd_t'; did you mean 'pgd_t'?
      88 |                                             pmd_t pmd)
         |                                             ^~~~~
         |                                             pgd_t
   include/linux/page_table_check.h:97:65: error: unknown type name 'pud_t'; did you mean 'pgd_t'?
      97 |                                             unsigned long addr, pud_t *pudp,
         |                                                                 ^~~~~
         |                                                                 pgd_t
   include/linux/page_table_check.h:98:45: error: unknown type name 'pud_t'; did you mean 'pgd_t'?
      98 |                                             pud_t pud)
         |                                             ^~~~~
         |                                             pgd_t
   include/linux/page_table_check.h:108:53: error: unknown type name 'pmd_t'; did you mean 'pgd_t'?
     108 |                                                     pmd_t pmd)
         |                                                     ^~~~~
         |                                                     pgd_t
   make[2]: *** [scripts/Makefile.build:114: arch/powerpc/kernel/asm-offsets.s] Error 1
   make[2]: Target 'prepare' not remade because of errors.
   make[1]: *** [Makefile:1286: prepare0] Error 2
   make[1]: Target 'prepare' not remade because of errors.
   make: *** [Makefile:242: __sub-make] Error 2
   make: Target 'prepare' not remade because of errors.


vim +20 include/linux/page_table_check.h

df4e817b710809 Pasha Tatashin 2022-01-14  15  
df4e817b710809 Pasha Tatashin 2022-01-14  16  void __page_table_check_zero(struct page *page, unsigned int order);
df4e817b710809 Pasha Tatashin 2022-01-14  17  void __page_table_check_pte_clear(struct mm_struct *mm, unsigned long addr,
df4e817b710809 Pasha Tatashin 2022-01-14  18  				  pte_t pte);
df4e817b710809 Pasha Tatashin 2022-01-14  19  void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr,
df4e817b710809 Pasha Tatashin 2022-01-14 @20  				  pmd_t pmd);
df4e817b710809 Pasha Tatashin 2022-01-14  21  void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr,
df4e817b710809 Pasha Tatashin 2022-01-14 @22  				  pud_t pud);
df4e817b710809 Pasha Tatashin 2022-01-14  23  void __page_table_check_pte_set(struct mm_struct *mm, unsigned long addr,
df4e817b710809 Pasha Tatashin 2022-01-14  24  				pte_t *ptep, pte_t pte);
df4e817b710809 Pasha Tatashin 2022-01-14  25  void __page_table_check_pmd_set(struct mm_struct *mm, unsigned long addr,
df4e817b710809 Pasha Tatashin 2022-01-14  26  				pmd_t *pmdp, pmd_t pmd);
df4e817b710809 Pasha Tatashin 2022-01-14  27  void __page_table_check_pud_set(struct mm_struct *mm, unsigned long addr,
df4e817b710809 Pasha Tatashin 2022-01-14  28  				pud_t *pudp, pud_t pud);
80110bbfbba6f0 Pasha Tatashin 2022-02-03  29  void __page_table_check_pte_clear_range(struct mm_struct *mm,
80110bbfbba6f0 Pasha Tatashin 2022-02-03  30  					unsigned long addr,
80110bbfbba6f0 Pasha Tatashin 2022-02-03  31  					pmd_t pmd);
df4e817b710809 Pasha Tatashin 2022-01-14  32
diff mbox series

Patch

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 2c9cdf1d8761..2474e2699037 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -154,6 +154,7 @@  config PPC
 	select ARCH_STACKWALK
 	select ARCH_SUPPORTS_ATOMIC_RMW
 	select ARCH_SUPPORTS_DEBUG_PAGEALLOC	if PPC_BOOK3S || PPC_8xx || 40x
+	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
 	select ARCH_USE_BUILTIN_BSWAP
 	select ARCH_USE_CMPXCHG_LOCKREF		if PPC64
 	select ARCH_USE_MEMTEST
diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
index afd672e84791..8850b4fb22a4 100644
--- a/arch/powerpc/include/asm/book3s/32/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
@@ -53,6 +53,8 @@ 
 
 #ifndef __ASSEMBLY__
 
+#include <linux/page_table_check.h>
+
 static inline bool pte_user(pte_t pte)
 {
 	return pte_val(pte) & _PAGE_USER;
@@ -338,7 +340,11 @@  static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 				       pte_t *ptep)
 {
-	return __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0));
+	pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0));
+
+	page_table_check_pte_clear(mm, addr, old_pte);
+
+	return old_pte;
 }
 
 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index a6ed93d01da1..0c6838875720 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -162,6 +162,8 @@ 
 #define PAGE_KERNEL_ROX	__pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX)
 
 #ifndef __ASSEMBLY__
+#include <linux/page_table_check.h>
+
 /*
  * page table defines
  */
@@ -431,8 +433,11 @@  static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
 				       unsigned long addr, pte_t *ptep)
 {
-	unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0, 0);
-	return __pte(old);
+	pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0));
+
+	page_table_check_pte_clear(mm, addr, old_pte);
+
+	return old_pte;
 }
 
 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
@@ -441,11 +446,16 @@  static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
 					    pte_t *ptep, int full)
 {
 	if (full && radix_enabled()) {
+		pte_t old_pte;
+
 		/*
 		 * We know that this is a full mm pte clear and
 		 * hence can be sure there is no parallel set_pte.
 		 */
-		return radix__ptep_get_and_clear_full(mm, addr, ptep, full);
+		old_pte = radix__ptep_get_and_clear_full(mm, addr, ptep, full);
+		page_table_check_pte_clear(mm, addr, old_pte);
+
+		return old_pte;
 	}
 	return ptep_get_and_clear(mm, addr, ptep);
 }
@@ -1249,17 +1259,33 @@  extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
 					    unsigned long addr, pmd_t *pmdp)
 {
-	if (radix_enabled())
-		return radix__pmdp_huge_get_and_clear(mm, addr, pmdp);
-	return hash__pmdp_huge_get_and_clear(mm, addr, pmdp);
+	pmd_t old_pmd;
+
+	if (radix_enabled()) {
+		old_pmd = radix__pmdp_huge_get_and_clear(mm, addr, pmdp);
+	} else {
+		old_pmd = hash__pmdp_huge_get_and_clear(mm, addr, pmdp);
+	}
+
+	page_table_check_pmd_clear(mm, addr, old_pmd);
+
+	return old_pmd;
 }
 
 static inline pmd_t __pmdp_collapse_flush(struct vm_area_struct *vma, struct mm_struct *mm,
 					  unsigned long address, pmd_t *pmdp)
 {
-	if (radix_enabled())
-		return radix__pmdp_collapse_flush(vma, address, pmdp);
-	return hash__pmdp_collapse_flush(vma, address, pmdp);
+	pmd_t old_pmd;
+
+	if (radix_enabled()) {
+		old_pmd = radix__pmdp_collapse_flush(vma, address, pmdp);
+	} else {
+		old_pmd = hash__pmdp_collapse_flush(vma, address, pmdp);
+	}
+
+	page_table_check_pmd_clear(mm, address, old_pmd);
+
+	return old_pmd;
 }
 #define pmdp_collapse_flush(__vma, __addr, __pmdp)			\
 ({									\
diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index d953533c56ff..e9c77054fe0b 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -166,6 +166,7 @@  void unmap_kernel_page(unsigned long va);
 #define _PAGE_CHG_MASK	(PTE_RPN_MASK | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_SPECIAL)
 
 #ifndef __ASSEMBLY__
+#include <linux/page_table_check.h>
 
 #define pte_clear(mm, addr, ptep) \
 	do { pte_update(mm, addr, ptep, ~0, 0, 0); } while (0)
@@ -316,7 +317,11 @@  static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 				       pte_t *ptep)
 {
-	return __pte(pte_update(mm, addr, ptep, ~0, 0, 0));
+	pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0, 0, 0));
+
+	page_table_check_pte_clear(mm, addr, old_pte);
+
+	return old_pte;
 }
 
 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
index 14e69ebad31f..d88b22c753d3 100644
--- a/arch/powerpc/include/asm/nohash/64/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
@@ -83,6 +83,7 @@ 
 #define H_PAGE_4K_PFN 0
 
 #ifndef __ASSEMBLY__
+#include <linux/page_table_check.h>
 /* pte_clear moved to later in this file */
 
 static inline pte_t pte_mkwrite(pte_t pte)
@@ -259,8 +260,11 @@  static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
 				       unsigned long addr, pte_t *ptep)
 {
-	unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0, 0);
-	return __pte(old);
+	pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0));
+
+	page_table_check_pte_clear(mm, addr, old_pte);
+
+	return old_pte;
 }
 
 static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
index b76fdb80b6c9..5715350e603a 100644
--- a/arch/powerpc/include/asm/pgtable.h
+++ b/arch/powerpc/include/asm/pgtable.h
@@ -5,6 +5,7 @@ 
 #ifndef __ASSEMBLY__
 #include <linux/mmdebug.h>
 #include <linux/mmzone.h>
+#include <linux/page_table_check.h>
 #include <asm/processor.h>		/* For TASK_SIZE */
 #include <asm/mmu.h>
 #include <asm/page.h>
@@ -48,7 +49,7 @@  struct mm_struct;
 /* Keep these as a macros to avoid include dependency mess */
 #define pte_page(x)		pfn_to_page(pte_pfn(x))
 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
-#define set_pte_at  		set_pte
+
 /*
  * Select all bits except the pfn
  */
@@ -153,6 +154,13 @@  struct seq_file;
 void arch_report_meminfo(struct seq_file *m);
 #endif /* CONFIG_PPC64 */
 
+static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+			      pte_t *ptep, pte_t pte)
+{
+	page_table_check_pte_set(mm, addr, ptep, pte);
+	set_pte(mm, addr, ptep, pte);
+}
+
 /*
  * Currently only consumed by page_table_check_pud_{set,clear}. Since clears
  * and sets to page table entries at any level are done through
diff --git a/arch/powerpc/mm/book3s64/hash_pgtable.c b/arch/powerpc/mm/book3s64/hash_pgtable.c
index 51f48984abca..a92a8a7c9199 100644
--- a/arch/powerpc/mm/book3s64/hash_pgtable.c
+++ b/arch/powerpc/mm/book3s64/hash_pgtable.c
@@ -165,7 +165,7 @@  int hash__map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
 		ptep = pte_alloc_kernel(pmdp, ea);
 		if (!ptep)
 			return -ENOMEM;
-		set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot));
+		set_pte(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot));
 	} else {
 		/*
 		 * If the mm subsystem is not fully up, we cannot create a
diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
index 85c84e89e3ea..d95be1d08b79 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -9,6 +9,7 @@ 
 #include <linux/memremap.h>
 #include <linux/pkeys.h>
 #include <linux/debugfs.h>
+#include <linux/page_table_check.h>
 #include <misc/cxl-base.h>
 
 #include <asm/pgalloc.h>
@@ -87,7 +88,10 @@  void set_pmd_at(struct mm_struct *mm, unsigned long addr,
 	WARN_ON(!(pmd_large(pmd)));
 #endif
 	trace_hugepage_set_pmd(addr, pmd_val(pmd));
-	return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd));
+
+	page_table_check_pmd_set(mm, addr, pmdp, pmd);
+
+	return set_pte(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd));
 }
 
 static void do_serialize(void *arg)
@@ -122,11 +126,13 @@  void serialize_against_pte_lookup(struct mm_struct *mm)
 pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
 		     pmd_t *pmdp)
 {
-	unsigned long old_pmd;
+	pmd_t old_pmd;
 
-	old_pmd = pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID);
+	old_pmd = __pmd(pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID));
 	flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
-	return __pmd(old_pmd);
+	page_table_check_pmd_clear(vma->vm_mm, address, old_pmd);
+
+	return old_pmd;
 }
 
 pmd_t pmdp_huge_get_and_clear_full(struct vm_area_struct *vma,
@@ -460,7 +466,7 @@  void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
 	if (radix_enabled())
 		return radix__ptep_modify_prot_commit(vma, addr,
 						      ptep, old_pte, pte);
-	set_pte_at(vma->vm_mm, addr, ptep, pte);
+	set_pte(vma->vm_mm, addr, ptep, pte);
 }
 
 /*
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 4e46e001c3c3..9359e3589107 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -110,7 +110,7 @@  static int early_map_kernel_page(unsigned long ea, unsigned long pa,
 	ptep = pte_offset_kernel(pmdp, ea);
 
 set_the_pte:
-	set_pte_at(&init_mm, ea, ptep, pfn_pte(pfn, flags));
+	set_pte(&init_mm, ea, ptep, pfn_pte(pfn, flags));
 	asm volatile("ptesync": : :"memory");
 	return 0;
 }
@@ -170,7 +170,7 @@  static int __map_kernel_page(unsigned long ea, unsigned long pa,
 		return -ENOMEM;
 
 set_the_pte:
-	set_pte_at(&init_mm, ea, ptep, pfn_pte(pfn, flags));
+	set_pte(&init_mm, ea, ptep, pfn_pte(pfn, flags));
 	asm volatile("ptesync": : :"memory");
 	return 0;
 }
@@ -1094,7 +1094,7 @@  void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
 	    (atomic_read(&mm->context.copros) > 0))
 		radix__flush_tlb_page(vma, addr);
 
-	set_pte_at(mm, addr, ptep, pte);
+	set_pte(mm, addr, ptep, pte);
 }
 
 int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
@@ -1105,7 +1105,7 @@  int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
 	if (!radix_enabled())
 		return 0;
 
-	set_pte_at(&init_mm, 0 /* radix unused */, ptep, new_pud);
+	set_pte(&init_mm, 0 /* radix unused */, ptep, new_pud);
 
 	return 1;
 }
@@ -1152,7 +1152,7 @@  int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
 	if (!radix_enabled())
 		return 0;
 
-	set_pte_at(&init_mm, 0 /* radix unused */, ptep, new_pmd);
+	set_pte(&init_mm, 0 /* radix unused */, ptep, new_pmd);
 
 	return 1;
 }
diff --git a/arch/powerpc/mm/nohash/book3e_pgtable.c b/arch/powerpc/mm/nohash/book3e_pgtable.c
index b80fc4a91a53..e50d22c6f983 100644
--- a/arch/powerpc/mm/nohash/book3e_pgtable.c
+++ b/arch/powerpc/mm/nohash/book3e_pgtable.c
@@ -111,7 +111,7 @@  int __ref map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
 		}
 		ptep = pte_offset_kernel(pmdp, ea);
 	}
-	set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot));
+	set_pte(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot));
 
 	smp_wmb();
 	return 0;
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 5c02fd08d61e..a86a16be24ea 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -89,7 +89,7 @@  int __ref map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot)
 		 * hash table
 		 */
 		BUG_ON((pte_present(*pg) | pte_hashpte(*pg)) && pgprot_val(prot));
-		set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, prot));
+		set_pte(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, prot));
 	}
 	smp_wmb();
 	return err;