diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/memory.h | 6 | ||||
| -rw-r--r-- | arch/arm64/kernel/traps.c | 2 | ||||
| -rw-r--r-- | arch/arm64/mm/fault.c | 15 |
3 files changed, 13 insertions, 10 deletions
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 32f82723338a..ef39dcb9ca6a 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -64,8 +64,10 @@ * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area. */ #define VA_BITS (CONFIG_ARM64_VA_BITS) -#define VA_START (UL(0xffffffffffffffff) << VA_BITS) -#define PAGE_OFFSET (UL(0xffffffffffffffff) << (VA_BITS - 1)) +#define VA_START (UL(0xffffffffffffffff) - \ + (UL(1) << VA_BITS) + 1) +#define PAGE_OFFSET (UL(0xffffffffffffffff) - \ + (UL(1) << (VA_BITS - 1)) + 1) #define KIMAGE_VADDR (MODULES_END) #define MODULES_END (MODULES_VADDR + MODULES_VSIZE) #define MODULES_VADDR (VA_START + KASAN_SHADOW_SIZE) diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index d48f47080213..8a62648848e5 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -523,7 +523,7 @@ static void cntfrq_read_handler(unsigned int esr, struct pt_regs *regs) { int rt = (esr & ESR_ELx_SYS64_ISS_RT_MASK) >> ESR_ELx_SYS64_ISS_RT_SHIFT; - pt_regs_write_reg(regs, rt, read_sysreg(cntfrq_el0)); + pt_regs_write_reg(regs, rt, arch_timer_get_rate()); regs->pc += 4; } diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index c7861c9864e6..2509e4fe6992 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -163,26 +163,27 @@ int ptep_set_access_flags(struct vm_area_struct *vma, /* only preserve the access flags and write permission */ pte_val(entry) &= PTE_AF | PTE_WRITE | PTE_DIRTY; - /* - * PTE_RDONLY is cleared by default in the asm below, so set it in - * back if necessary (read-only or clean PTE). - */ + /* set PTE_RDONLY if actual read-only or clean PTE */ if (!pte_write(entry) || !pte_sw_dirty(entry)) pte_val(entry) |= PTE_RDONLY; /* * Setting the flags must be done atomically to avoid racing with the - * hardware update of the access/dirty state. + * hardware update of the access/dirty state. The PTE_RDONLY bit must + * be set to the most permissive (lowest value) of *ptep and entry + * (calculated as: a & b == ~(~a | ~b)). */ + pte_val(entry) ^= PTE_RDONLY; asm volatile("// ptep_set_access_flags\n" " prfm pstl1strm, %2\n" "1: ldxr %0, %2\n" - " and %0, %0, %3 // clear PTE_RDONLY\n" + " eor %0, %0, %3 // negate PTE_RDONLY in *ptep\n" " orr %0, %0, %4 // set flags\n" + " eor %0, %0, %3 // negate final PTE_RDONLY\n" " stxr %w1, %0, %2\n" " cbnz %w1, 1b\n" : "=&r" (old_pteval), "=&r" (tmp), "+Q" (pte_val(*ptep)) - : "L" (~PTE_RDONLY), "r" (pte_val(entry))); + : "L" (PTE_RDONLY), "r" (pte_val(entry))); flush_tlb_fix_spurious_fault(vma, address); return 1; |