38  * Returns 0 if mmiotrace is disabled, or if the fault is not
120 	 * If it was a exec (instruction fetch) fault on NX page, then  in is_prefetch()
121 	 * do not ignore the fault:  in is_prefetch()
194  *   Handle a fault on the vmalloc or module mapping area
205  *   unhandled page-fault when they are accessed.
416  * The OS sees this as a page fault with the upper 32bits of RIP cleared.
450  * We catch this in the page fault handler because these addresses
536 		pr_alert("BUG: unable to handle page fault for address: %px\n",  in show_fault_oops()
559 		 * contributory exception from user code and gets a page fault  in show_fault_oops()
560 		 * during delivery, the page fault can be delivered as though  in show_fault_oops()
644 	/* Are we prepared to handle this kernel fault? */  in no_context()
647 		 * Any interrupt that takes a fault gets the fixup. This makes  in no_context()
648 		 * the below recursive fault logic only apply to a faults from  in no_context()
675 	 * Stack overflow?  During boot, we can fault near the initial  in no_context()
686 		 * double-fault even before we get this far, in which case  in no_context()
687 		 * we're fine: the double-fault handler will deal with it.  in no_context()
690 		 * and then double-fault, though, because we're likely to  in no_context()
697 			      : "D" ("kernel stack overflow (page fault)"),  in no_context()
707 	 *   Valid to do another page fault here, because if this fault  in no_context()
722 	 * Buggy firmware could access regions which might page fault, try to  in no_context()
800 		 * Valid to do another page fault here because this one came  in __bad_area_nosemaphore()
893 		 * A protection key fault means that the PKRU value did not allow  in bad_area_access_error()
900 		 * fault and that there was a VMA once we got in the fault  in bad_area_access_error()
908 		 * 5. T1   : enters fault handler, takes mmap_lock, etc...  in bad_area_access_error()
922 	  vm_fault_t fault)  in do_sigbus()  argument
930 	/* User-space => ok to do another page fault: */  in do_sigbus()
937 	if (fault & (VM_FAULT_HWPOISON|VM_FAULT_HWPOISON_LARGE)) {  in do_sigbus()
942 	"MCE: Killing %s:%d due to hardware memory corruption fault at %lx\n",  in do_sigbus()
944 		if (fault & VM_FAULT_HWPOISON_LARGE)  in do_sigbus()
945 			lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));  in do_sigbus()
946 		if (fault & VM_FAULT_HWPOISON)  in do_sigbus()
957 	       unsigned long address, vm_fault_t fault)  in mm_fault_error()  argument
964 	if (fault & VM_FAULT_OOM) {  in mm_fault_error()
974 		 * userspace (which will retry the fault, or kill us if we got  in mm_fault_error()
979 		if (fault & (VM_FAULT_SIGBUS|VM_FAULT_HWPOISON|  in mm_fault_error()
981 			do_sigbus(regs, error_code, address, fault);  in mm_fault_error()
982 		else if (fault & VM_FAULT_SIGSEGV)  in mm_fault_error()
1001  * Handle a spurious fault caused by a stale TLB entry.
1016  * Returns non-zero if a spurious fault was handled, zero otherwise.
1099 	 * a follow-up action to resolve the fault, like a COW.  in access_error()
1162 	 * We can fault-in kernel-space virtual memory on-demand. The  in do_kern_addr_fault()
1171 	 * fault is not any of the following:  in do_kern_addr_fault()
1172 	 * 1. A fault on a PTE with a reserved bit set.  in do_kern_addr_fault()
1173 	 * 2. A fault caused by a user-mode access.  (Do not demand-  in do_kern_addr_fault()
1174 	 *    fault kernel memory due to user-mode accesses).  in do_kern_addr_fault()
1175 	 * 3. A fault caused by a page-level protection violation.  in do_kern_addr_fault()
1176 	 *    (A demand fault would be on a non-present page which  in do_kern_addr_fault()
1191 	/* Was the fault spurious, caused by lazy TLB invalidation? */  in do_kern_addr_fault()
1202 	 * and handling kernel code that can fault, like get_user().  in do_kern_addr_fault()
1205 	 * fault we could otherwise deadlock:  in do_kern_addr_fault()
1220 	vm_fault_t fault;  in do_user_addr_fault()  local
1254 	 * in a region with pagefaults disabled then we must not take the fault  in do_user_addr_fault()
1263 	 * vmalloc fault has been handled.  in do_user_addr_fault()
1266 	 * potential system fault or CPU buglet:  in do_user_addr_fault()
1304 	 * tables.  But, an erroneous kernel fault occurring outside one of  in do_user_addr_fault()
1306 	 * to validate the fault against the address space.  in do_user_addr_fault()
1316 			 * Fault from code in kernel from  in do_user_addr_fault()
1360 	 * If for any reason at all we couldn't handle the fault,  in do_user_addr_fault()
1362 	 * the fault.  Since we never set FAULT_FLAG_RETRY_NOWAIT, if  in do_user_addr_fault()
1367 	 * repeat the page fault later with a VM_FAULT_NOPAGE retval  in do_user_addr_fault()
1372 	fault = handle_mm_fault(vma, address, flags, regs);  in do_user_addr_fault()
1375 	if (fault_signal_pending(fault, regs)) {  in do_user_addr_fault()
1387 	if (unlikely((fault & VM_FAULT_RETRY) &&  in do_user_addr_fault()
1394 	if (unlikely(fault & VM_FAULT_ERROR)) {  in do_user_addr_fault()
1395 		mm_fault_error(regs, hw_error_code, address, fault);  in do_user_addr_fault()
1425 	/* Was the fault on kernel-controlled part of the address space? */  in handle_page_fault()
1431 		 * User address page fault handling might have reenabled  in handle_page_fault()
1450 	 * (asynchronous page fault mechanism). The event happens when a  in DEFINE_IDTENTRY_RAW_ERRORCODE()
1475 	 * be invoked because a kernel fault on a user space address might  in DEFINE_IDTENTRY_RAW_ERRORCODE()
1478 	 * In case the fault hit a RCU idle region the conditional entry  in DEFINE_IDTENTRY_RAW_ERRORCODE()