diff options
| author | Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> | 2020-11-27 10:14:10 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-12-04 01:01:25 +1100 |
| commit | d94b827e89dc3f92cd871d10f4992a6bd3c861e5 (patch) | |
| tree | cf3fd6317c4c6b93f539381c2bd0d081f272b88c /arch/powerpc/include | |
| parent | d5b810b5c938e73fd21b2b05ef6a79837eeaa305 (diff) | |
powerpc/book3s64/kuap: Use Key 3 for kernel mapping with hash translation
This patch updates kernel hash page table entries to use storage key 3
for its mapping. This implies all kernel access will now use key 3 to
control READ/WRITE. The patch also prevents the allocation of key 3 from
userspace and UAMOR value is updated such that userspace cannot modify key 3.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201127044424.40686-9-aneesh.kumar@linux.ibm.com
Diffstat (limited to 'arch/powerpc/include')
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/hash-pkey.h | 25 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/hash.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/mmu-hash.h | 1 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/mmu_context.h | 2 |
4 files changed, 22 insertions, 8 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/hash-pkey.h b/arch/powerpc/include/asm/book3s/64/hash-pkey.h index 795010897e5d..f1e60d579f6c 100644 --- a/arch/powerpc/include/asm/book3s/64/hash-pkey.h +++ b/arch/powerpc/include/asm/book3s/64/hash-pkey.h @@ -2,6 +2,9 @@ #ifndef _ASM_POWERPC_BOOK3S_64_HASH_PKEY_H #define _ASM_POWERPC_BOOK3S_64_HASH_PKEY_H +/* We use key 3 for KERNEL */ +#define HASH_DEFAULT_KERNEL_KEY (HPTE_R_KEY_BIT0 | HPTE_R_KEY_BIT1) + static inline u64 hash__vmflag_to_pte_pkey_bits(u64 vm_flags) { return (((vm_flags & VM_PKEY_BIT0) ? H_PTE_PKEY_BIT0 : 0x0UL) | @@ -11,13 +14,23 @@ static inline u64 hash__vmflag_to_pte_pkey_bits(u64 vm_flags) ((vm_flags & VM_PKEY_BIT4) ? H_PTE_PKEY_BIT4 : 0x0UL)); } -static inline u64 pte_to_hpte_pkey_bits(u64 pteflags) +static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags) { - return (((pteflags & H_PTE_PKEY_BIT4) ? HPTE_R_KEY_BIT4 : 0x0UL) | - ((pteflags & H_PTE_PKEY_BIT3) ? HPTE_R_KEY_BIT3 : 0x0UL) | - ((pteflags & H_PTE_PKEY_BIT2) ? HPTE_R_KEY_BIT2 : 0x0UL) | - ((pteflags & H_PTE_PKEY_BIT1) ? HPTE_R_KEY_BIT1 : 0x0UL) | - ((pteflags & H_PTE_PKEY_BIT0) ? HPTE_R_KEY_BIT0 : 0x0UL)); + unsigned long pte_pkey; + + pte_pkey = (((pteflags & H_PTE_PKEY_BIT4) ? HPTE_R_KEY_BIT4 : 0x0UL) | + ((pteflags & H_PTE_PKEY_BIT3) ? HPTE_R_KEY_BIT3 : 0x0UL) | + ((pteflags & H_PTE_PKEY_BIT2) ? HPTE_R_KEY_BIT2 : 0x0UL) | + ((pteflags & H_PTE_PKEY_BIT1) ? HPTE_R_KEY_BIT1 : 0x0UL) | + ((pteflags & H_PTE_PKEY_BIT0) ? HPTE_R_KEY_BIT0 : 0x0UL)); + + if (mmu_has_feature(MMU_FTR_BOOK3S_KUAP) || + mmu_has_feature(MMU_FTR_BOOK3S_KUEP)) { + if ((pte_pkey == 0) && (flags & HPTE_USE_KERNEL_KEY)) + return HASH_DEFAULT_KERNEL_KEY; + } + + return pte_pkey; } static inline u16 hash__pte_to_pkey_bits(u64 pteflags) diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h index 73ad038ed10b..d959b0195ad9 100644 --- a/arch/powerpc/include/asm/book3s/64/hash.h +++ b/arch/powerpc/include/asm/book3s/64/hash.h @@ -145,7 +145,7 @@ extern void hash__mark_initmem_nx(void); extern void hpte_need_flush(struct mm_struct *mm, unsigned long addr, pte_t *ptep, unsigned long pte, int huge); -extern unsigned long htab_convert_pte_flags(unsigned long pteflags); +unsigned long htab_convert_pte_flags(unsigned long pteflags, unsigned long flags); /* Atomic PTE updates */ static inline unsigned long hash__pte_update(struct mm_struct *mm, unsigned long addr, diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h index 683a9c7d1b03..9192cb05a6ab 100644 --- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h +++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h @@ -452,6 +452,7 @@ static inline unsigned long hpt_hash(unsigned long vpn, #define HPTE_LOCAL_UPDATE 0x1 #define HPTE_NOHPTE_UPDATE 0x2 +#define HPTE_USE_KERNEL_KEY 0x4 extern int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid, pte_t *ptep, unsigned long trap, diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h index e5a5e3cb7724..033d2f39ed28 100644 --- a/arch/powerpc/include/asm/mmu_context.h +++ b/arch/powerpc/include/asm/mmu_context.h @@ -286,7 +286,7 @@ static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, #define thread_pkey_regs_init(thread) #define arch_dup_pkeys(oldmm, mm) -static inline u64 pte_to_hpte_pkey_bits(u64 pteflags) +static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags) { return 0x0UL; } |