diff options
Diffstat (limited to 'arch/arm64/mm/fault.c')
| -rw-r--r-- | arch/arm64/mm/fault.c | 74 |
1 files changed, 26 insertions, 48 deletions
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 6045a5117ac1..3fe516b32577 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -66,6 +66,8 @@ static inline const struct fault_info *esr_to_debug_fault_info(unsigned long esr static void data_abort_decode(unsigned long esr) { + unsigned long iss2 = ESR_ELx_ISS2(esr); + pr_alert("Data abort info:\n"); if (esr & ESR_ELx_ISV) { @@ -78,12 +80,21 @@ static void data_abort_decode(unsigned long esr) (esr & ESR_ELx_SF) >> ESR_ELx_SF_SHIFT, (esr & ESR_ELx_AR) >> ESR_ELx_AR_SHIFT); } else { - pr_alert(" ISV = 0, ISS = 0x%08lx\n", esr & ESR_ELx_ISS_MASK); + pr_alert(" ISV = 0, ISS = 0x%08lx, ISS2 = 0x%08lx\n", + esr & ESR_ELx_ISS_MASK, iss2); } - pr_alert(" CM = %lu, WnR = %lu\n", + pr_alert(" CM = %lu, WnR = %lu, TnD = %lu, TagAccess = %lu\n", (esr & ESR_ELx_CM) >> ESR_ELx_CM_SHIFT, - (esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT); + (esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT, + (iss2 & ESR_ELx_TnD) >> ESR_ELx_TnD_SHIFT, + (iss2 & ESR_ELx_TagAccess) >> ESR_ELx_TagAccess_SHIFT); + + pr_alert(" GCS = %ld, Overlay = %lu, DirtyBit = %lu, Xs = %llu\n", + (iss2 & ESR_ELx_GCS) >> ESR_ELx_GCS_SHIFT, + (iss2 & ESR_ELx_Overlay) >> ESR_ELx_Overlay_SHIFT, + (iss2 & ESR_ELx_DirtyBit) >> ESR_ELx_DirtyBit_SHIFT, + (iss2 & ESR_ELx_Xs_MASK) >> ESR_ELx_Xs_SHIFT); } static void mem_abort_decode(unsigned long esr) @@ -177,6 +188,9 @@ static void show_pte(unsigned long addr) break; ptep = pte_offset_map(pmdp, addr); + if (!ptep) + break; + pte = READ_ONCE(*ptep); pr_cont(", pte=%016llx", pte_val(pte)); pte_unmap(ptep); @@ -317,7 +331,7 @@ static void report_tag_fault(unsigned long addr, unsigned long esr, * find out access size. */ bool is_write = !!(esr & ESR_ELx_WNR); - kasan_report(addr, 0, is_write, regs->pc); + kasan_report((void *)addr, 0, is_write, regs->pc); } #else /* Tag faults aren't enabled without CONFIG_KASAN_HW_TAGS. */ @@ -483,27 +497,14 @@ static void do_bad_area(unsigned long far, unsigned long esr, #define VM_FAULT_BADMAP ((__force vm_fault_t)0x010000) #define VM_FAULT_BADACCESS ((__force vm_fault_t)0x020000) -static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr, +static vm_fault_t __do_page_fault(struct mm_struct *mm, + struct vm_area_struct *vma, unsigned long addr, unsigned int mm_flags, unsigned long vm_flags, struct pt_regs *regs) { - struct vm_area_struct *vma = find_vma(mm, addr); - - if (unlikely(!vma)) - return VM_FAULT_BADMAP; - /* * Ok, we have a good vm_area for this memory access, so we can handle * it. - */ - if (unlikely(vma->vm_start > addr)) { - if (!(vma->vm_flags & VM_GROWSDOWN)) - return VM_FAULT_BADMAP; - if (expand_stack(vma, addr)) - return VM_FAULT_BADMAP; - } - - /* * Check that the permissions on the VMA allow for the fault which * occurred. */ @@ -535,9 +536,7 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, unsigned long vm_flags; unsigned int mm_flags = FAULT_FLAG_DEFAULT; unsigned long addr = untagged_addr(far); -#ifdef CONFIG_PER_VMA_LOCK struct vm_area_struct *vma; -#endif if (kprobe_page_fault(regs, esr)) return 0; @@ -617,31 +616,15 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, } lock_mmap: #endif /* CONFIG_PER_VMA_LOCK */ - /* - * As per x86, we may deadlock here. However, since the kernel only - * validly references user space from well defined areas of the code, - * we can bug out early if this is from code which shouldn't. - */ - if (!mmap_read_trylock(mm)) { - if (!user_mode(regs) && !search_exception_tables(regs->pc)) - goto no_context; + retry: - mmap_read_lock(mm); - } else { - /* - * The above mmap_read_trylock() might have succeeded in which - * case, we'll have missed the might_sleep() from down_read(). - */ - might_sleep(); -#ifdef CONFIG_DEBUG_VM - if (!user_mode(regs) && !search_exception_tables(regs->pc)) { - mmap_read_unlock(mm); - goto no_context; - } -#endif + vma = lock_mm_and_find_vma(mm, addr, regs); + if (unlikely(!vma)) { + fault = VM_FAULT_BADMAP; + goto done; } - fault = __do_page_fault(mm, addr, mm_flags, vm_flags, regs); + fault = __do_page_fault(mm, vma, addr, mm_flags, vm_flags, regs); /* Quick path to respond to signals */ if (fault_signal_pending(fault, regs)) { @@ -660,9 +643,7 @@ retry: } mmap_read_unlock(mm); -#ifdef CONFIG_PER_VMA_LOCK done: -#endif /* * Handle the "normal" (no error) case first. */ @@ -885,9 +866,6 @@ void do_sp_pc_abort(unsigned long addr, unsigned long esr, struct pt_regs *regs) } NOKPROBE_SYMBOL(do_sp_pc_abort); -int __init early_brk64(unsigned long addr, unsigned long esr, - struct pt_regs *regs); - /* * __refdata because early_brk64 is __init, but the reference to it is * clobbered at arch_initcall time. |