aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--arch/cris/mm/fault.c169
1 files changed, 28 insertions, 141 deletions
diff --git a/arch/cris/mm/fault.c b/arch/cris/mm/fault.c
index 3034f3ff950c..c4c76db90f9c 100644
--- a/arch/cris/mm/fault.c
+++ b/arch/cris/mm/fault.c
@@ -1,130 +1,9 @@
1/* 1/*
2 * linux/arch/cris/mm/fault.c 2 * linux/arch/cris/mm/fault.c
3 * 3 *
4 * Copyright (C) 2000, 2001 Axis Communications AB 4 * Copyright (C) 2000-2006 Axis Communications AB
5 *
6 * Authors: Bjorn Wesen
7 *
8 * $Log: fault.c,v $
9 * Revision 1.20 2005/03/04 08:16:18 starvik
10 * Merge of Linux 2.6.11.
11 *
12 * Revision 1.19 2005/01/14 10:07:59 starvik
13 * Fixed warning.
14 *
15 * Revision 1.18 2005/01/12 08:10:14 starvik
16 * Re-added the change of frametype when handling kernel page fault fixup
17 * for v10. This is necessary to avoid that the CPU remakes the faulting
18 * access.
19 *
20 * Revision 1.17 2005/01/11 13:53:05 starvik
21 * Use raw_printk.
22 *
23 * Revision 1.16 2004/12/17 11:39:41 starvik
24 * SMP support.
25 *
26 * Revision 1.15 2004/11/23 18:36:18 starvik
27 * Stack is now non-executable.
28 * Signal handler trampolines are placed in a reserved page mapped into all
29 * processes.
30 *
31 * Revision 1.14 2004/11/23 07:10:21 starvik
32 * Moved find_fixup_code to generic code.
33 *
34 * Revision 1.13 2004/11/23 07:00:54 starvik
35 * Actually use the execute permission bit in the MMU. This makes it possible
36 * to prevent e.g. attacks where executable code is put on the stack.
37 *
38 * Revision 1.12 2004/09/29 06:16:04 starvik
39 * Use instruction_pointer
40 *
41 * Revision 1.11 2004/05/14 07:58:05 starvik
42 * Merge of changes from 2.4
43 *
44 * Revision 1.10 2003/10/27 14:51:24 starvik
45 * Removed debugcode
46 *
47 * Revision 1.9 2003/10/27 14:50:42 starvik
48 * Changed do_page_fault signature
49 *
50 * Revision 1.8 2003/07/04 13:02:48 tobiasa
51 * Moved code snippet from arch/cris/mm/fault.c that searches for fixup code
52 * to separate function in arch-specific files.
53 *
54 * Revision 1.7 2003/01/22 06:48:38 starvik
55 * Fixed warnings issued by GCC 3.2.1
56 *
57 * Revision 1.6 2003/01/09 14:42:52 starvik
58 * Merge of Linux 2.5.55
59 *
60 * Revision 1.5 2002/12/11 14:44:48 starvik
61 * Extracted v10 (ETRAX 100LX) specific stuff to arch/cris/arch-v10/mm
62 *
63 * Revision 1.4 2002/11/13 15:10:28 starvik
64 * pte_offset has been renamed to pte_offset_kernel
65 *
66 * Revision 1.3 2002/11/05 06:45:13 starvik
67 * Merge of Linux 2.5.45
68 *
69 * Revision 1.2 2001/12/18 13:35:22 bjornw
70 * Applied the 2.4.13->2.4.16 CRIS patch to 2.5.1 (is a copy of 2.4.15).
71 *
72 * Revision 1.20 2001/11/22 13:34:06 bjornw
73 * * Bug workaround (LX TR89): force a rerun of the whole of an interrupted
74 * unaligned write, because the second half of the write will be corrupted
75 * otherwise. Affected unaligned writes spanning not-yet mapped pages.
76 * * Optimization: use the wr_rd bit in R_MMU_CAUSE to know whether a miss
77 * was due to a read or a write (before we didn't know this until the next
78 * restart of the interrupted instruction, thus wasting one fault-irq)
79 *
80 * Revision 1.19 2001/11/12 19:02:10 pkj
81 * Fixed compiler warnings.
82 *
83 * Revision 1.18 2001/07/18 22:14:32 bjornw
84 * Enable interrupts in the bulk of do_page_fault
85 *
86 * Revision 1.17 2001/07/18 13:07:23 bjornw
87 * * Detect non-existant PTE's in vmalloc pmd synchronization
88 * * Remove comment about fast-paths for VMALLOC_START etc, because all that
89 * was totally bogus anyway it turned out :)
90 * * Fix detection of vmalloc-area synchronization
91 * * Add some comments
92 *
93 * Revision 1.16 2001/06/13 00:06:08 bjornw
94 * current_pgd should be volatile
95 *
96 * Revision 1.15 2001/06/13 00:02:23 bjornw
97 * Use a separate variable to store the current pgd to avoid races in schedule
98 *
99 * Revision 1.14 2001/05/16 17:41:07 hp
100 * Last comment tweak further tweaked.
101 *
102 * Revision 1.13 2001/05/15 00:58:44 hp
103 * Expand a bit on the comment why we compare address >= TASK_SIZE rather
104 * than >= VMALLOC_START.
105 *
106 * Revision 1.12 2001/04/04 10:51:14 bjornw
107 * mmap_sem is grabbed for reading
108 *
109 * Revision 1.11 2001/03/23 07:36:07 starvik
110 * Corrected according to review remarks
111 *
112 * Revision 1.10 2001/03/21 16:10:11 bjornw
113 * CRIS_FRAME_FIXUP not needed anymore, use FRAME_NORMAL
114 *
115 * Revision 1.9 2001/03/05 13:22:20 bjornw
116 * Spell-fix and fix in vmalloc_fault handling
117 *
118 * Revision 1.8 2000/11/22 14:45:31 bjornw
119 * * 2.4.0-test10 removed the set_pgdir instantaneous kernel global mapping
120 * into all processes. Instead we fill in the missing PTE entries on demand.
121 *
122 * Revision 1.7 2000/11/21 16:39:09 bjornw
123 * fixup switches frametype
124 *
125 * Revision 1.6 2000/11/17 16:54:08 bjornw
126 * More detailed siginfo reporting
127 * 5 *
6 * Authors: Bjorn Wesen
128 * 7 *
129 */ 8 */
130 9
@@ -135,7 +14,6 @@
135 14
136extern int find_fixup_code(struct pt_regs *); 15extern int find_fixup_code(struct pt_regs *);
137extern void die_if_kernel(const char *, struct pt_regs *, long); 16extern void die_if_kernel(const char *, struct pt_regs *, long);
138extern int raw_printk(const char *fmt, ...);
139 17
140/* debug of low-level TLB reload */ 18/* debug of low-level TLB reload */
141#undef DEBUG 19#undef DEBUG
@@ -164,8 +42,8 @@ unsigned long cris_signal_return_page;
164 * address. 42 * address.
165 * 43 *
166 * error_code: 44 * error_code:
167 * bit 0 == 0 means no page found, 1 means protection fault 45 * bit 0 == 0 means no page found, 1 means protection fault
168 * bit 1 == 0 means read, 1 means write 46 * bit 1 == 0 means read, 1 means write
169 * 47 *
170 * If this routine detects a bad access, it returns 1, otherwise it 48 * If this routine detects a bad access, it returns 1, otherwise it
171 * returns 0. 49 * returns 0.
@@ -181,9 +59,10 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
181 siginfo_t info; 59 siginfo_t info;
182 int fault; 60 int fault;
183 61
184 D(printk("Page fault for %lX on %X at %lX, prot %d write %d\n", 62 D(printk(KERN_DEBUG
185 address, smp_processor_id(), instruction_pointer(regs), 63 "Page fault for %lX on %X at %lX, prot %d write %d\n",
186 protection, writeaccess)); 64 address, smp_processor_id(), instruction_pointer(regs),
65 protection, writeaccess));
187 66
188 tsk = current; 67 tsk = current;
189 68
@@ -233,7 +112,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
233 * context, we must not take the fault.. 112 * context, we must not take the fault..
234 */ 113 */
235 114
236 if (in_atomic() || !mm) 115 if (in_interrupt() || !mm)
237 goto no_context; 116 goto no_context;
238 117
239 down_read(&mm->mmap_sem); 118 down_read(&mm->mmap_sem);
@@ -319,6 +198,9 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
319 /* info.si_code has been set above */ 198 /* info.si_code has been set above */
320 info.si_addr = (void *)address; 199 info.si_addr = (void *)address;
321 force_sig_info(SIGSEGV, &info, tsk); 200 force_sig_info(SIGSEGV, &info, tsk);
201 printk(KERN_NOTICE "%s (pid %d) segfaults for page "
202 "address %08lx at pc %08lx\n",
203 tsk->comm, tsk->pid, address, instruction_pointer(regs));
322 return; 204 return;
323 } 205 }
324 206
@@ -326,7 +208,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
326 208
327 /* Are we prepared to handle this kernel fault? 209 /* Are we prepared to handle this kernel fault?
328 * 210 *
329 * (The kernel has valid exception-points in the source 211 * (The kernel has valid exception-points in the source
330 * when it acesses user-memory. When it fails in one 212 * when it acesses user-memory. When it fails in one
331 * of those points, we find it in a table and do a jump 213 * of those points, we find it in a table and do a jump
332 * to some fixup code that loads an appropriate error 214 * to some fixup code that loads an appropriate error
@@ -341,13 +223,18 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
341 * terminate things with extreme prejudice. 223 * terminate things with extreme prejudice.
342 */ 224 */
343 225
344 if ((unsigned long) (address) < PAGE_SIZE) 226 if (!oops_in_progress) {
345 raw_printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference"); 227 oops_in_progress = 1;
346 else 228 if ((unsigned long) (address) < PAGE_SIZE)
347 raw_printk(KERN_ALERT "Unable to handle kernel access"); 229 printk(KERN_ALERT "Unable to handle kernel NULL "
348 raw_printk(" at virtual address %08lx\n",address); 230 "pointer dereference");
349 231 else
350 die_if_kernel("Oops", regs, (writeaccess << 1) | protection); 232 printk(KERN_ALERT "Unable to handle kernel access"
233 " at virtual address %08lx\n", address);
234
235 die_if_kernel("Oops", regs, (writeaccess << 1) | protection);
236 oops_in_progress = 0;
237 }
351 238
352 do_exit(SIGKILL); 239 do_exit(SIGKILL);
353 240
@@ -360,7 +247,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
360 up_read(&mm->mmap_sem); 247 up_read(&mm->mmap_sem);
361 printk("VM: killing process %s\n", tsk->comm); 248 printk("VM: killing process %s\n", tsk->comm);
362 if (user_mode(regs)) 249 if (user_mode(regs))
363 do_group_exit(SIGKILL); 250 do_exit(SIGKILL);
364 goto no_context; 251 goto no_context;
365 252
366 do_sigbus: 253 do_sigbus:
@@ -406,8 +293,8 @@ vmalloc_fault:
406 /* Since we're two-level, we don't need to do both 293 /* Since we're two-level, we don't need to do both
407 * set_pgd and set_pmd (they do the same thing). If 294 * set_pgd and set_pmd (they do the same thing). If
408 * we go three-level at some point, do the right thing 295 * we go three-level at some point, do the right thing
409 * with pgd_present and set_pgd here. 296 * with pgd_present and set_pgd here.
410 * 297 *
411 * Also, since the vmalloc area is global, we don't 298 * Also, since the vmalloc area is global, we don't
412 * need to copy individual PTE's, it is enough to 299 * need to copy individual PTE's, it is enough to
413 * copy the pgd pointer into the pte page of the 300 * copy the pgd pointer into the pte page of the