11da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 21da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * linux/arch/frv/mm/fault.c 31da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 41da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. 51da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * - Written by David Howells (dhowells@redhat.com) 61da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * - Derived from arch/m68knommu/mm/fault.c 71da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * - Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>, 81da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * - Copyright (C) 2000 Lineo, Inc. (www.lineo.com) 91da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Based on: 111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * linux/arch/m68k/mm/fault.c 131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Copyright (C) 1995 Hamish Macdonald 151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/mman.h> 181da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/mm.h> 191da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/kernel.h> 201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/ptrace.h> 211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/hardirq.h> 221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 231da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <asm/pgtable.h> 241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <asm/uaccess.h> 251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <asm/gdb-stub.h> 261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/*****************************************************************************/ 281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * This routine handles page faults. It determines the problem, and 301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * then passes it off to one of the appropriate routines. 311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsasmlinkage void do_page_fault(int datammu, unsigned long esr0, unsigned long ear0) 331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct vm_area_struct *vma; 351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct mm_struct *mm; 361da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds unsigned long _pme, lrai, lrad, fixup; 37759496ba6407c6994d6a5ce3a5e74937d7816208Johannes Weiner unsigned long flags = 0; 381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds siginfo_t info; 391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pgd_t *pge; 401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pud_t *pue; 411da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pte_t *pte; 4283c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin int fault; 431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#if 0 451da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds const char *atxc[16] = { 461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds [0x0] = "mmu-miss", [0x8] = "multi-dat", [0x9] = "multi-sat", 471da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds [0xa] = "tlb-miss", [0xc] = "privilege", [0xd] = "write-prot", 481da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds }; 491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 501da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk("do_page_fault(%d,%lx [%s],%lx)\n", 511da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds datammu, esr0, atxc[esr0 >> 20 & 0xf], ear0); 521da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#endif 531da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 541da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds mm = current->mm; 551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* 571da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * We fault-in kernel-space virtual memory on-demand. The 581da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 'reference' page table is init_mm.pgd. 591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * NOTE! We MUST NOT take any locks for this case. We may 611da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * be in an interrupt or a critical region, and should 621da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * only copy the information from the master page table, 631da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * nothing more. 641da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 651da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * This verifies that the fault happens in kernel space 661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * and that the fault was a page not present (invalid) error 671da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 681da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!user_mode(__frame) && (esr0 & ESR0_ATXC) == ESR0_ATXC_AMRTLB_MISS) { 691da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (ear0 >= VMALLOC_START && ear0 < VMALLOC_END) 701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto kernel_pte_fault; 711da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (ear0 >= PKMAP_BASE && ear0 < PKMAP_END) 721da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto kernel_pte_fault; 731da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 741da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 751da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_code = SEGV_MAPERR; 761da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 771da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* 781da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * If we're in an interrupt or have no user 791da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * context, we must not take the fault.. 801da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 816edaf68a87d17570790fd55f0c451a29ec1d6703Peter Zijlstra if (in_atomic() || !mm) 821da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto no_context; 831da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 84759496ba6407c6994d6a5ce3a5e74937d7816208Johannes Weiner if (user_mode(__frame)) 85759496ba6407c6994d6a5ce3a5e74937d7816208Johannes Weiner flags |= FAULT_FLAG_USER; 86759496ba6407c6994d6a5ce3a5e74937d7816208Johannes Weiner 871da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds down_read(&mm->mmap_sem); 881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 891da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds vma = find_vma(mm, ear0); 901da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!vma) 911da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto bad_area; 921da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (vma->vm_start <= ear0) 931da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto good_area; 941da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!(vma->vm_flags & VM_GROWSDOWN)) 951da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto bad_area; 961da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 971da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (user_mode(__frame)) { 981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* 991da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * accessing the stack below %esp is always a bug. 1001da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * The "+ 32" is there due to some instructions (like 1011da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * pusha) doing post-decrement on the stack and that 1021da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * doesn't show up until later.. 1031da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 1041da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if ((ear0 & PAGE_MASK) + 2 * PAGE_SIZE < __frame->sp) { 1051da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#if 0 1061da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk("[%d] ### Access below stack @%lx (sp=%lx)\n", 1071da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds current->pid, ear0, __frame->sp); 1081da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds show_registers(__frame); 1091da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk("[%d] ### Code: [%08lx] %02x %02x %02x %02x %02x %02x %02x %02x\n", 1101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds current->pid, 1111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds __frame->pc, 1121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ((u8*)__frame->pc)[0], 1131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ((u8*)__frame->pc)[1], 1141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ((u8*)__frame->pc)[2], 1151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ((u8*)__frame->pc)[3], 1161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ((u8*)__frame->pc)[4], 1171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ((u8*)__frame->pc)[5], 1181da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ((u8*)__frame->pc)[6], 1191da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ((u8*)__frame->pc)[7] 1201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ); 1211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#endif 1221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto bad_area; 1231da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 1241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 1251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (expand_stack(vma, ear0)) 1271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto bad_area; 1281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 1301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Ok, we have a good vm_area for this memory access, so 1311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * we can handle it.. 1321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 1331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds good_area: 1341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_code = SEGV_ACCERR; 1351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds switch (esr0 & ESR0_ATXC) { 1361da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds default: 1371da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* handle write to write protected page */ 1381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds case ESR0_ATXC_WP_EXCEP: 1391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#ifdef TEST_VERIFY_AREA 1401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!(user_mode(__frame))) 1411da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk("WP fault at %08lx\n", __frame->pc); 1421da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#endif 1431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!(vma->vm_flags & VM_WRITE)) 1441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto bad_area; 145759496ba6407c6994d6a5ce3a5e74937d7816208Johannes Weiner flags |= FAULT_FLAG_WRITE; 1461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds break; 1471da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1481da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* handle read from protected page */ 1491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds case ESR0_ATXC_PRIV_EXCEP: 1501da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto bad_area; 1511da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1521da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* handle read, write or exec on absent page 1531da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * - can't support write without permitting read 1541da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * - don't support execute without permitting read and vice-versa 1551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 1561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds case ESR0_ATXC_AMRTLB_MISS: 1571da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!(vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC))) 1581da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto bad_area; 1591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds break; 1601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 1611da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1621da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* 1631da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * If for any reason at all we couldn't handle the fault, 1641da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * make sure we exit gracefully rather than endlessly redo 1651da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * the fault. 1661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 167759496ba6407c6994d6a5ce3a5e74937d7816208Johannes Weiner fault = handle_mm_fault(mm, vma, ear0, flags); 16883c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin if (unlikely(fault & VM_FAULT_ERROR)) { 16983c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin if (fault & VM_FAULT_OOM) 17083c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin goto out_of_memory; 17183c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin else if (fault & VM_FAULT_SIGBUS) 17283c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin goto do_sigbus; 17383c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin BUG(); 1741da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 17583c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin if (fault & VM_FAULT_MAJOR) 17683c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin current->maj_flt++; 17783c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin else 17883c54070ee1a2d05c89793884bea1a03f2851ed4Nick Piggin current->min_flt++; 1791da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1801da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds up_read(&mm->mmap_sem); 1811da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return; 1821da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1831da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 1841da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Something tried to access memory that isn't in our memory map.. 1851da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Fix it, but check if it's kernel or user first.. 1861da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 1871da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds bad_area: 1881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds up_read(&mm->mmap_sem); 1891da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1901da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* User mode accesses just cause a SIGSEGV */ 1911da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (user_mode(__frame)) { 1921da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_signo = SIGSEGV; 1931da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_errno = 0; 1941da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* info.si_code has been set above */ 1951da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_addr = (void *) ear0; 1961da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds force_sig_info(SIGSEGV, &info, current); 1971da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return; 1981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 1991da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2001da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds no_context: 2011da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* are we prepared to handle this kernel fault? */ 2021da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if ((fixup = search_exception_table(__frame->pc)) != 0) { 2031da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds __frame->pc = fixup; 2041da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return; 2051da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 2061da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2071da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 2081da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Oops. The kernel tried to access some bad page. We'll have to 2091da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * terminate things with extreme prejudice. 2101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 2111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds bust_spinlocks(1); 2131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (ear0 < PAGE_SIZE) 2151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference"); 2161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds else 2171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(KERN_ALERT "Unable to handle kernel paging request"); 2181da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(" at virtual addr %08lx\n", ear0); 2191da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(" PC : %08lx\n", __frame->pc); 2201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(" EXC : esr0=%08lx ear0=%08lx\n", esr0, ear0); 2211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds asm("lrai %1,%0,#1,#0,#0" : "=&r"(lrai) : "r"(ear0)); 2231da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds asm("lrad %1,%0,#1,#0,#0" : "=&r"(lrad) : "r"(ear0)); 2241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(KERN_ALERT " LRAI: %08lx\n", lrai); 2261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(KERN_ALERT " LRAD: %08lx\n", lrad); 2271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds __break_hijack_kernel_event(); 2291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pge = pgd_offset(current->mm, ear0); 2311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pue = pud_offset(pge, ear0); 2321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds _pme = pue->pue[0].ste[0]; 2331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(KERN_ALERT " PGE : %8p { PME %08lx }\n", pge, _pme); 2351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2361da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (_pme & xAMPRx_V) { 2371da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds unsigned long dampr, damlr, val; 2381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds asm volatile("movsg dampr2,%0 ! movgs %2,dampr2 ! movsg damlr2,%1" 2401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds : "=&r"(dampr), "=r"(damlr) 2411da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds : "r" (_pme | xAMPRx_L|xAMPRx_SS_16Kb|xAMPRx_S|xAMPRx_C|xAMPRx_V) 2421da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ); 2431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pte = (pte_t *) damlr + __pte_index(ear0); 2451da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds val = pte_val(*pte); 2461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2471da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds asm volatile("movgs %0,dampr2" :: "r" (dampr)); 2481da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds printk(KERN_ALERT " PTE : %8p { %08lx }\n", pte, val); 2501da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 2511da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2521da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds die_if_kernel("Oops\n"); 2531da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds do_exit(SIGKILL); 2541da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 2561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * We ran out of memory, or some other thing happened to us that made 2571da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * us unable to handle the page fault gracefully. 2581da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 2591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds out_of_memory: 2601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds up_read(&mm->mmap_sem); 261f9c497c4aea28be826b8450a5339952f2ffc705eNick Piggin if (!user_mode(__frame)) 262f9c497c4aea28be826b8450a5339952f2ffc705eNick Piggin goto no_context; 263f9c497c4aea28be826b8450a5339952f2ffc705eNick Piggin pagefault_out_of_memory(); 264f9c497c4aea28be826b8450a5339952f2ffc705eNick Piggin return; 2651da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds do_sigbus: 2671da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds up_read(&mm->mmap_sem); 2681da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2691da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* 2701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Send a sigbus, regardless of whether we were in kernel 2711da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * or user mode. 2721da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 2731da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_signo = SIGBUS; 2741da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_errno = 0; 2751da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_code = BUS_ADRERR; 2761da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds info.si_addr = (void *) ear0; 2771da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds force_sig_info(SIGBUS, &info, current); 2781da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2791da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* Kernel mode? Handle exceptions or die */ 2801da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!user_mode(__frame)) 2811da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto no_context; 2821da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return; 2831da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2841da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 2851da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * The fault was caused by a kernel PTE (such as installed by vmalloc or kmap) 2861da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 2871da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds kernel_pte_fault: 2881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds { 2891da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds /* 2901da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Synchronize this task's top level page-table 2911da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * with the 'reference' page table. 2921da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 2931da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Do _not_ use "tsk" here. We might be inside 2941da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * an interrupt in the middle of a task switch.. 2951da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 2961da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int index = pgd_index(ear0); 2971da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pgd_t *pgd, *pgd_k; 2981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pud_t *pud, *pud_k; 2991da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pmd_t *pmd, *pmd_k; 3001da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pte_t *pte_k; 3011da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3021da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pgd = (pgd_t *) __get_TTBR(); 3031da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pgd = (pgd_t *)__va(pgd) + index; 3041da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pgd_k = ((pgd_t *)(init_mm.pgd)) + index; 3051da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3061da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!pgd_present(*pgd_k)) 3071da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto no_context; 3081da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds //set_pgd(pgd, *pgd_k); /////// gcc ICE's on this line 3091da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pud_k = pud_offset(pgd_k, ear0); 3111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!pud_present(*pud_k)) 3121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto no_context; 3131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pmd_k = pmd_offset(pud_k, ear0); 3151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!pmd_present(*pmd_k)) 3161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto no_context; 3171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3181da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pud = pud_offset(pgd, ear0); 3191da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pmd = pmd_offset(pud, ear0); 3201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds set_pmd(pmd, *pmd_k); 3211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 3221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds pte_k = pte_offset_kernel(pmd_k, ear0); 3231da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!pte_present(*pte_k)) 3241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds goto no_context; 3251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return; 3261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 3271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} /* end do_page_fault() */ 328