3  * Based on arch/arm/mm/fault.c
291 	 * If we now have a valid translation, treat the translation fault as  in is_spurious_el1_translation_fault()
298 	 * If we got a different type of fault from the AT instruction,  in is_spurious_el1_translation_fault()
299 	 * treat the translation fault as spurious.  in is_spurious_el1_translation_fault()
349 	 * tag fault.  in do_tag_recovery()
375 	 * Are we prepared to handle this kernel fault?  in __do_kernel_fault()
382 	    "Ignoring spurious kernel translation fault at virtual address %016lx\n", addr))  in __do_kernel_fault()
423 	 * an alignment fault not caused by the memory type would take  in set_thread_esr()
424 	 * precedence over translation fault for a real access to empty  in set_thread_esr()
425 	 * space. Unfortunately we can't easily distinguish "alignment fault  in set_thread_esr()
426 	 * not caused by memory type" from "alignment fault caused by memory  in set_thread_esr()
428 	 * fault.)  in set_thread_esr()
438 			 * We always report the ESR as if the fault was taken  in set_thread_esr()
440 			 * clear. (In fact it always will be a fault to EL1.)  in set_thread_esr()
448 			 * Claim a level 0 translation fault.  in set_thread_esr()
478 	 * handle this fault with.  in do_bad_area()
514  * should fault. EL0 cannot issue DC IVAC (undef).
526 	vm_fault_t fault;  in do_page_fault()  local
539 	 * the fault.  in do_page_fault()
549 	 * for the fault to be benign, __do_page_fault() would check  in do_page_fault()
554 		/* It was exec fault */  in do_page_fault()
558 		/* It was write fault */  in do_page_fault()
562 		/* It was read fault */  in do_page_fault()
592 		fault = 0;  in do_page_fault()
601 		fault = 0;  in do_page_fault()
607 	fault = handle_mm_fault(vma, addr, mm_flags | FAULT_FLAG_VMA_LOCK, regs);  in do_page_fault()
608 	if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED)))  in do_page_fault()
611 	if (!(fault & VM_FAULT_RETRY)) {  in do_page_fault()
616 	if (fault & VM_FAULT_MAJOR)  in do_page_fault()
620 	if (fault_signal_pending(fault, regs)) {  in do_page_fault()
630 		fault = 0;  in do_page_fault()
637 		fault = 0;  in do_page_fault()
645 		fault = 0;  in do_page_fault()
650 	fault = handle_mm_fault(vma, addr, mm_flags, regs);  in do_page_fault()
653 	if (fault_signal_pending(fault, regs)) {  in do_page_fault()
659 	/* The fault is fully completed (including releasing mmap lock) */  in do_page_fault()
660 	if (fault & VM_FAULT_COMPLETED)  in do_page_fault()
663 	if (fault & VM_FAULT_RETRY) {  in do_page_fault()
671 	if (likely(!(fault & VM_FAULT_ERROR)))  in do_page_fault()
678 	 * handle this fault with.  in do_page_fault()
683 	if (fault & VM_FAULT_OOM) {  in do_page_fault()
686 		 * userspace (which will retry the fault, or kill us if we got  in do_page_fault()
695 	if (fault & VM_FAULT_SIGBUS) {  in do_page_fault()
698 		 * this page fault.  in do_page_fault()
701 	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {  in do_page_fault()
705 		if (fault & VM_FAULT_HWPOISON_LARGE)  in do_page_fault()
706 			lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));  in do_page_fault()
712 		 * from the pkey that caused the fault.  in do_page_fault()
718 		 * 5. T1   : enters fault handler, takes mmap_lock, etc...  in do_page_fault()
761 	return 1; /* "fault" */  in do_bad()
808 	{ do_bad,		SIGKILL, SI_KERNEL,	"ttbr address size fault"	},
809 	{ do_bad,		SIGKILL, SI_KERNEL,	"level 1 address size fault"	},
810 	{ do_bad,		SIGKILL, SI_KERNEL,	"level 2 address size fault"	},
811 	{ do_bad,		SIGKILL, SI_KERNEL,	"level 3 address size fault"	},
812 	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 0 translation fault"	},
813 	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 1 translation fault"	},
814 	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 2 translation fault"	},
815 	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 3 translation fault"	},
816 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 0 access flag fault"	},
817 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 1 access flag fault"	},
818 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 2 access flag fault"	},
819 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 3 access flag fault"	},
820 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 0 permission fault"	},
821 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 1 permission fault"	},
822 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 2 permission fault"	},
823 	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 3 permission fault"	},
825 	{ do_tag_check_fault,	SIGSEGV, SEGV_MTESERR,	"synchronous tag check fault"	},
841 	{ do_alignment_fault,	SIGBUS,  BUS_ADRALN,	"alignment fault"		},
849 	{ do_bad,		SIGKILL, SI_KERNEL,	"level -1 address size fault"	},
851 	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level -1 translation fault"	},
857 	{ do_bad,		SIGKILL, SI_KERNEL,	"Unsupported atomic hardware update fault"	},
860 	{ do_bad,		SIGKILL, SI_KERNEL,	"implementation fault (lockdown abort)" },
861 	{ do_bad,		SIGBUS,  BUS_OBJERR,	"implementation fault (unsupported exclusive)" },
869 	{ do_bad,		SIGKILL, SI_KERNEL,	"section domain fault"		},
870 	{ do_bad,		SIGKILL, SI_KERNEL,	"page domain fault"		},
886 	 * At this point we have an unrecognized fault type whose tag bits may  in do_mem_abort()
971  * Used during anonymous page fault handling.