case 2:
case VM_FAULT_MAJOR:
asmlinkage void do_page_fault(int datammu, unsigned long esr0, unsigned long ear0){	struct vm_area_struct *vma;	struct mm_struct *mm;	unsigned long _pme, lrai, lrad, fixup;	siginfo_t info;	pgd_t *pge;	pud_t *pue;	pte_t *pte;	int write;#if 0	const char *atxc[16] = {		[0x0] = "mmu-miss", [0x8] = "multi-dat", [0x9] = "multi-sat",		[0xa] = "tlb-miss", [0xc] = "privilege", [0xd] = "write-prot",	};	printk("do_page_fault(%d,%lx [%s],%lx)\n",	       datammu, esr0, atxc[esr0 >> 20 & 0xf], ear0);#endif	mm = current->mm;	/*	 * We fault-in kernel-space virtual memory on-demand. The	 * 'reference' page table is init_mm.pgd.	 *	 * NOTE! We MUST NOT take any locks for this case. We may	 * be in an interrupt or a critical region, and should	 * only copy the information from the master page table,	 * nothing more.	 *	 * This verifies that the fault happens in kernel space	 * and that the fault was a page not present (invalid) error	 */	if (!user_mode(__frame) && (esr0 & ESR0_ATXC) == ESR0_ATXC_AMRTLB_MISS) {		if (ear0 >= VMALLOC_START && ear0 < VMALLOC_END)			goto kernel_pte_fault;		if (ear0 >= PKMAP_BASE && ear0 < PKMAP_END)			goto kernel_pte_fault;	}	info.si_code = SEGV_MAPERR;	/*	 * If we're in an interrupt or have no user	 * context, we must not take the fault..	 */	if (in_interrupt() || !mm)		goto no_context;	down_read(&mm->mmap_sem);	vma = find_vma(mm, ear0);	if (!vma)		goto bad_area;	if (vma->vm_start <= ear0)		goto good_area;	if (!(vma->vm_flags & VM_GROWSDOWN))		goto bad_area;	if (user_mode(__frame)) {		/*		 * accessing the stack below %esp is always a bug.		 * The "+ 32" is there due to some instructions (like		 * pusha) doing post-decrement on the stack and that		 * doesn't show up until later..		 */		if ((ear0 & PAGE_MASK) + 2 * PAGE_SIZE < __frame->sp) {#if 0			printk("[%d] ### Access below stack @%lx (sp=%lx)\n",			       current->pid, ear0, __frame->sp);			show_registers(__frame);			printk("[%d] ### Code: [%08lx] %02x %02x %02x %02x %02x %02x %02x %02x\n",			       current->pid,			       __frame->pc,			       ((u8*)__frame->pc)[0],			       ((u8*)__frame->pc)[1],			       ((u8*)__frame->pc)[2],			       ((u8*)__frame->pc)[3],			       ((u8*)__frame->pc)[4],			       ((u8*)__frame->pc)[5],			       ((u8*)__frame->pc)[6],			       ((u8*)__frame->pc)[7]			       );#endif			goto bad_area;		}	}	if (expand_stack(vma, ear0))		goto bad_area;/* * Ok, we have a good vm_area for this memory access, so * we can handle it.. */ good_area:	info.si_code = SEGV_ACCERR;	write = 0;	switch (esr0 & ESR0_ATXC) {	default:		/* handle write to write protected page */	case ESR0_ATXC_WP_EXCEP:#ifdef TEST_VERIFY_AREA		if (!(user_mode(__frame)))			printk("WP fault at %08lx\n", __frame->pc);#endif		if (!(vma->vm_flags & VM_WRITE))			goto bad_area;		write = 1;		break;		 /* handle read from protected page */	case ESR0_ATXC_PRIV_EXCEP:		goto bad_area;		 /* handle read, write or exec on absent page		  * - can't support write without permitting read		  * - don't support execute without permitting read and vice-versa		  */	case ESR0_ATXC_AMRTLB_MISS:		if (!(vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)))			goto bad_area;		break;	}	/*	 * If for any reason at all we couldn't handle the fault,	 * make sure we exit gracefully rather than endlessly redo	 * the fault.	 */	switch (handle_mm_fault(mm, vma, ear0, write)) {	case 1:		current->min_flt++;		break;	case 2:		current->maj_flt++;		break;	case 0:		goto do_sigbus;	default:		goto out_of_memory;	}	up_read(&mm->mmap_sem);	return;/* * Something tried to access memory that isn't in our memory map.. * Fix it, but check if it's kernel or user first.. */ bad_area:	up_read(&mm->mmap_sem);	/* User mode accesses just cause a SIGSEGV */	if (user_mode(__frame)) {		info.si_signo = SIGSEGV;		info.si_errno = 0;		/* info.si_code has been set above */		info.si_addr = (void *) ear0;		force_sig_info(SIGSEGV, &info, current);		return;	} no_context:	/* are we prepared to handle this kernel fault? */	if ((fixup = search_exception_table(__frame->pc)) != 0) {		__frame->pc = fixup;		return;	}/* * Oops. The kernel tried to access some bad page. We'll have to * terminate things with extreme prejudice. */	bust_spinlocks(1);	if (ear0 < PAGE_SIZE)		printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");	else		printk(KERN_ALERT "Unable to handle kernel paging request");	printk(" at virtual addr %08lx\n", ear0);	printk("  PC  : %08lx\n", __frame->pc);	printk("  EXC : esr0=%08lx ear0=%08lx\n", esr0, ear0);	asm("lrai %1,%0,#1,#0,#0" : "=&r"(lrai) : "r"(ear0));	asm("lrad %1,%0,#1,#0,#0" : "=&r"(lrad) : "r"(ear0));	printk(KERN_ALERT "  LRAI: %08lx\n", lrai);	printk(KERN_ALERT "  LRAD: %08lx\n", lrad);	__break_hijack_kernel_event();	pge = pgd_offset(current->mm, ear0);	pue = pud_offset(pge, ear0);	_pme = pue->pue[0].ste[0];	printk(KERN_ALERT "  PGE : %8p { PME %08lx }\n", pge, _pme);	if (_pme & xAMPRx_V) {		unsigned long dampr, damlr, val;		asm volatile("movsg dampr2,%0 ! movgs %2,dampr2 ! movsg damlr2,%1"			     : "=&r"(dampr), "=r"(damlr)			     : "r" (_pme | xAMPRx_L|xAMPRx_SS_16Kb|xAMPRx_S|xAMPRx_C|xAMPRx_V)			     );		pte = (pte_t *) damlr + __pte_index(ear0);		val = pte_val(*pte);		asm volatile("movgs %0,dampr2" :: "r" (dampr));		printk(KERN_ALERT "  PTE : %8p { %08lx }\n", pte, val);	}	die_if_kernel("Oops\n");	do_exit(SIGKILL);/* * We ran out of memory, or some other thing happened to us that made * us unable to handle the page fault gracefully. */ out_of_memory:	up_read(&mm->mmap_sem);	printk("VM: killing process %s\n", current->comm);	if (user_mode(__frame))		do_exit(SIGKILL);	goto no_context; do_sigbus:	up_read(&mm->mmap_sem);	/*	 * Send a sigbus, regardless of whether we were in kernel	 * or user mode.	 */	info.si_signo = SIGBUS;	info.si_errno = 0;	info.si_code = BUS_ADRERR;	info.si_addr = (void *) ear0;	force_sig_info(SIGBUS, &info, current);	/* Kernel mode? Handle exceptions or die */	if (!user_mode(__frame))		goto no_context;	return;/* * The fault was caused by a kernel PTE (such as installed by vmalloc or kmap) */ kernel_pte_fault:	{		/*		 * Synchronize this task's top level page-table		 * with the 'reference' page table.		 *		 * Do _not_ use "tsk" here. We might be inside		 * an interrupt in the middle of a task switch..		 */		int index = pgd_index(ear0);		pgd_t *pgd, *pgd_k;		pud_t *pud, *pud_k;		pmd_t *pmd, *pmd_k;		pte_t *pte_k;		pgd = (pgd_t *) __get_TTBR();		pgd = (pgd_t *)__va(pgd) + index;		pgd_k = ((pgd_t *)(init_mm.pgd)) + index;		if (!pgd_present(*pgd_k))			goto no_context;		//set_pgd(pgd, *pgd_k); /////// gcc ICE's on this line		pud_k = pud_offset(pgd_k, ear0);		if (!pud_present(*pud_k))			goto no_context;		pmd_k = pmd_offset(pud_k, ear0);		if (!pmd_present(*pmd_k))			goto no_context;		pud = pud_offset(pgd, ear0);		pmd = pmd_offset(pud, ear0);		set_pmd(pmd, *pmd_k);		pte_k = pte_offset_kernel(pmd_k, ear0);		if (!pte_present(*pte_k))			goto no_context;		return;	}} /* end do_page_fault() */