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authorDave Jones <davej@redhat.com>2007-02-10 20:36:29 -0500
committerDave Jones <davej@redhat.com>2007-02-10 20:36:29 -0500
commitbd0561c9d8dcbf21cd9aa46c416bbf6a3a12e4b1 (patch)
tree64fe15d4db42e0840acea00e4cf7e1855bba9e96 /arch/s390/mm/fault.c
parent348f31ed2bd18391fe5903aa0ad7bfcda6d8ca0b (diff)
parent66efc5a7e3061c3597ac43a8bb1026488d57e66b (diff)
[CPUFREQ] Fix up merge conflicts with recent ACPI changes.
Signed-off-by: Dave Jones <davej@redhat.com>
Diffstat (limited to 'arch/s390/mm/fault.c')
-rw-r--r--arch/s390/mm/fault.c93
1 files changed, 88 insertions, 5 deletions
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index cd85e34d8703..9ff143e87746 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -52,7 +52,7 @@ extern int sysctl_userprocess_debug;
52extern void die(const char *,struct pt_regs *,long); 52extern void die(const char *,struct pt_regs *,long);
53 53
54#ifdef CONFIG_KPROBES 54#ifdef CONFIG_KPROBES
55ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain); 55static ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
56int register_page_fault_notifier(struct notifier_block *nb) 56int register_page_fault_notifier(struct notifier_block *nb)
57{ 57{
58 return atomic_notifier_chain_register(&notify_page_fault_chain, nb); 58 return atomic_notifier_chain_register(&notify_page_fault_chain, nb);
@@ -137,7 +137,9 @@ static int __check_access_register(struct pt_regs *regs, int error_code)
137 137
138/* 138/*
139 * Check which address space the address belongs to. 139 * Check which address space the address belongs to.
140 * Returns 1 for user space and 0 for kernel space. 140 * May return 1 or 2 for user space and 0 for kernel space.
141 * Returns 2 for user space in primary addressing mode with
142 * CONFIG_S390_EXEC_PROTECT on and kernel parameter noexec=on.
141 */ 143 */
142static inline int check_user_space(struct pt_regs *regs, int error_code) 144static inline int check_user_space(struct pt_regs *regs, int error_code)
143{ 145{
@@ -154,7 +156,7 @@ static inline int check_user_space(struct pt_regs *regs, int error_code)
154 return __check_access_register(regs, error_code); 156 return __check_access_register(regs, error_code);
155 if (descriptor == 2) 157 if (descriptor == 2)
156 return current->thread.mm_segment.ar4; 158 return current->thread.mm_segment.ar4;
157 return descriptor != 0; 159 return ((descriptor != 0) ^ (switch_amode)) << s390_noexec;
158} 160}
159 161
160/* 162/*
@@ -183,6 +185,77 @@ static void do_sigsegv(struct pt_regs *regs, unsigned long error_code,
183 force_sig_info(SIGSEGV, &si, current); 185 force_sig_info(SIGSEGV, &si, current);
184} 186}
185 187
188#ifdef CONFIG_S390_EXEC_PROTECT
189extern long sys_sigreturn(struct pt_regs *regs);
190extern long sys_rt_sigreturn(struct pt_regs *regs);
191extern long sys32_sigreturn(struct pt_regs *regs);
192extern long sys32_rt_sigreturn(struct pt_regs *regs);
193
194static inline void do_sigreturn(struct mm_struct *mm, struct pt_regs *regs,
195 int rt)
196{
197 up_read(&mm->mmap_sem);
198 clear_tsk_thread_flag(current, TIF_SINGLE_STEP);
199#ifdef CONFIG_COMPAT
200 if (test_tsk_thread_flag(current, TIF_31BIT)) {
201 if (rt)
202 sys32_rt_sigreturn(regs);
203 else
204 sys32_sigreturn(regs);
205 return;
206 }
207#endif /* CONFIG_COMPAT */
208 if (rt)
209 sys_rt_sigreturn(regs);
210 else
211 sys_sigreturn(regs);
212 return;
213}
214
215static int signal_return(struct mm_struct *mm, struct pt_regs *regs,
216 unsigned long address, unsigned long error_code)
217{
218 pgd_t *pgd;
219 pmd_t *pmd;
220 pte_t *pte;
221 u16 *instruction;
222 unsigned long pfn, uaddr = regs->psw.addr;
223
224 spin_lock(&mm->page_table_lock);
225 pgd = pgd_offset(mm, uaddr);
226 if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
227 goto out_fault;
228 pmd = pmd_offset(pgd, uaddr);
229 if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
230 goto out_fault;
231 pte = pte_offset_map(pmd_offset(pgd_offset(mm, uaddr), uaddr), uaddr);
232 if (!pte || !pte_present(*pte))
233 goto out_fault;
234 pfn = pte_pfn(*pte);
235 if (!pfn_valid(pfn))
236 goto out_fault;
237 spin_unlock(&mm->page_table_lock);
238
239 instruction = (u16 *) ((pfn << PAGE_SHIFT) + (uaddr & (PAGE_SIZE-1)));
240 if (*instruction == 0x0a77)
241 do_sigreturn(mm, regs, 0);
242 else if (*instruction == 0x0aad)
243 do_sigreturn(mm, regs, 1);
244 else {
245 printk("- XXX - do_exception: task = %s, primary, NO EXEC "
246 "-> SIGSEGV\n", current->comm);
247 up_read(&mm->mmap_sem);
248 current->thread.prot_addr = address;
249 current->thread.trap_no = error_code;
250 do_sigsegv(regs, error_code, SEGV_MAPERR, address);
251 }
252 return 0;
253out_fault:
254 spin_unlock(&mm->page_table_lock);
255 return -EFAULT;
256}
257#endif /* CONFIG_S390_EXEC_PROTECT */
258
186/* 259/*
187 * This routine handles page faults. It determines the address, 260 * This routine handles page faults. It determines the address,
188 * and the problem, and then passes it off to one of the appropriate 261 * and the problem, and then passes it off to one of the appropriate
@@ -260,6 +333,17 @@ do_exception(struct pt_regs *regs, unsigned long error_code, int is_protection)
260 vma = find_vma(mm, address); 333 vma = find_vma(mm, address);
261 if (!vma) 334 if (!vma)
262 goto bad_area; 335 goto bad_area;
336
337#ifdef CONFIG_S390_EXEC_PROTECT
338 if (unlikely((user_address == 2) && !(vma->vm_flags & VM_EXEC)))
339 if (!signal_return(mm, regs, address, error_code))
340 /*
341 * signal_return() has done an up_read(&mm->mmap_sem)
342 * if it returns 0.
343 */
344 return;
345#endif
346
263 if (vma->vm_start <= address) 347 if (vma->vm_start <= address)
264 goto good_area; 348 goto good_area;
265 if (!(vma->vm_flags & VM_GROWSDOWN)) 349 if (!(vma->vm_flags & VM_GROWSDOWN))
@@ -452,8 +536,7 @@ void pfault_fini(void)
452 : : "a" (&refbk), "m" (refbk) : "cc"); 536 : : "a" (&refbk), "m" (refbk) : "cc");
453} 537}
454 538
455asmlinkage void 539static void pfault_interrupt(__u16 error_code)
456pfault_interrupt(__u16 error_code)
457{ 540{
458 struct task_struct *tsk; 541 struct task_struct *tsk;
459 __u16 subcode; 542 __u16 subcode;