Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Copyright (C) 1995 Linus Torvalds |
3 | * | |
4 | * Pentium III FXSR, SSE support | |
5 | * Gareth Hughes <gareth@valinux.com>, May 2000 | |
6612538c | 6 | * |
1da177e4 LT |
7 | * X86-64 port |
8 | * Andi Kleen. | |
76e4f660 AR |
9 | * |
10 | * CPU hotplug support - ashok.raj@intel.com | |
1da177e4 LT |
11 | */ |
12 | ||
13 | /* | |
14 | * This file handles the architecture-dependent parts of process handling.. | |
15 | */ | |
16 | ||
42059429 | 17 | #include <linux/stackprotector.h> |
76e4f660 | 18 | #include <linux/cpu.h> |
1da177e4 LT |
19 | #include <linux/errno.h> |
20 | #include <linux/sched.h> | |
6612538c | 21 | #include <linux/fs.h> |
1da177e4 LT |
22 | #include <linux/kernel.h> |
23 | #include <linux/mm.h> | |
24 | #include <linux/elfcore.h> | |
25 | #include <linux/smp.h> | |
26 | #include <linux/slab.h> | |
27 | #include <linux/user.h> | |
1da177e4 | 28 | #include <linux/interrupt.h> |
6612538c | 29 | #include <linux/utsname.h> |
1da177e4 | 30 | #include <linux/delay.h> |
6612538c | 31 | #include <linux/module.h> |
1da177e4 | 32 | #include <linux/ptrace.h> |
95833c83 | 33 | #include <linux/notifier.h> |
c6fd91f0 | 34 | #include <linux/kprobes.h> |
1eeb66a1 | 35 | #include <linux/kdebug.h> |
02290683 | 36 | #include <linux/tick.h> |
529e25f6 | 37 | #include <linux/prctl.h> |
7de08b4e GP |
38 | #include <linux/uaccess.h> |
39 | #include <linux/io.h> | |
8b96f011 | 40 | #include <linux/ftrace.h> |
48ec4d95 | 41 | #include <linux/dmi.h> |
1da177e4 | 42 | |
1da177e4 LT |
43 | #include <asm/pgtable.h> |
44 | #include <asm/system.h> | |
1da177e4 LT |
45 | #include <asm/processor.h> |
46 | #include <asm/i387.h> | |
47 | #include <asm/mmu_context.h> | |
1da177e4 | 48 | #include <asm/prctl.h> |
1da177e4 LT |
49 | #include <asm/desc.h> |
50 | #include <asm/proto.h> | |
51 | #include <asm/ia32.h> | |
95833c83 | 52 | #include <asm/idle.h> |
bbc1f698 | 53 | #include <asm/syscalls.h> |
bf53de90 | 54 | #include <asm/ds.h> |
1da177e4 LT |
55 | |
56 | asmlinkage extern void ret_from_fork(void); | |
57 | ||
c6f5e0ac BG |
58 | DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task; |
59 | EXPORT_PER_CPU_SYMBOL(current_task); | |
60 | ||
3d1e42a7 | 61 | DEFINE_PER_CPU(unsigned long, old_rsp); |
c2558e0e | 62 | static DEFINE_PER_CPU(unsigned char, is_idle); |
3d1e42a7 | 63 | |
1da177e4 LT |
64 | unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED; |
65 | ||
e041c683 | 66 | static ATOMIC_NOTIFIER_HEAD(idle_notifier); |
95833c83 AK |
67 | |
68 | void idle_notifier_register(struct notifier_block *n) | |
69 | { | |
e041c683 | 70 | atomic_notifier_chain_register(&idle_notifier, n); |
95833c83 | 71 | } |
c7d87d79 VP |
72 | EXPORT_SYMBOL_GPL(idle_notifier_register); |
73 | ||
74 | void idle_notifier_unregister(struct notifier_block *n) | |
75 | { | |
76 | atomic_notifier_chain_unregister(&idle_notifier, n); | |
77 | } | |
78 | EXPORT_SYMBOL_GPL(idle_notifier_unregister); | |
95833c83 | 79 | |
95833c83 AK |
80 | void enter_idle(void) |
81 | { | |
c2558e0e | 82 | percpu_write(is_idle, 1); |
e041c683 | 83 | atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL); |
95833c83 AK |
84 | } |
85 | ||
86 | static void __exit_idle(void) | |
87 | { | |
c2558e0e | 88 | if (x86_test_and_clear_bit_percpu(0, is_idle) == 0) |
a15da49d | 89 | return; |
e041c683 | 90 | atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL); |
95833c83 AK |
91 | } |
92 | ||
93 | /* Called from interrupts to signify idle end */ | |
94 | void exit_idle(void) | |
95 | { | |
a15da49d AK |
96 | /* idle loop has pid 0 */ |
97 | if (current->pid) | |
95833c83 AK |
98 | return; |
99 | __exit_idle(); | |
100 | } | |
101 | ||
913da64b | 102 | #ifndef CONFIG_SMP |
76e4f660 AR |
103 | static inline void play_dead(void) |
104 | { | |
105 | BUG(); | |
106 | } | |
913da64b | 107 | #endif |
76e4f660 | 108 | |
1da177e4 LT |
109 | /* |
110 | * The idle thread. There's no useful work to be | |
111 | * done, so just try to conserve power and have a | |
112 | * low exit latency (ie sit in a loop waiting for | |
113 | * somebody to say that they'd like to reschedule) | |
114 | */ | |
b10db7f0 | 115 | void cpu_idle(void) |
1da177e4 | 116 | { |
495ab9c0 | 117 | current_thread_info()->status |= TS_POLLING; |
ce22bd92 | 118 | |
ce22bd92 | 119 | /* |
5c79d2a5 TH |
120 | * If we're the non-boot CPU, nothing set the stack canary up |
121 | * for us. CPU0 already has it initialized but no harm in | |
122 | * doing it again. This is a good place for updating it, as | |
123 | * we wont ever return from this function (so the invalid | |
124 | * canaries already on the stack wont ever trigger). | |
ce22bd92 | 125 | */ |
18aa8bb1 IM |
126 | boot_init_stack_canary(); |
127 | ||
1da177e4 LT |
128 | /* endless idle loop with no priority at all */ |
129 | while (1) { | |
b8f8c3cf | 130 | tick_nohz_stop_sched_tick(1); |
1da177e4 | 131 | while (!need_resched()) { |
1da177e4 | 132 | |
1da177e4 | 133 | rmb(); |
6ddd2a27 | 134 | |
76e4f660 AR |
135 | if (cpu_is_offline(smp_processor_id())) |
136 | play_dead(); | |
d331e739 VP |
137 | /* |
138 | * Idle routines should keep interrupts disabled | |
139 | * from here on, until they go to idle. | |
140 | * Otherwise, idle callbacks can misfire. | |
141 | */ | |
142 | local_irq_disable(); | |
95833c83 | 143 | enter_idle(); |
81d68a96 SR |
144 | /* Don't trace irqs off for idle */ |
145 | stop_critical_timings(); | |
6ddd2a27 | 146 | pm_idle(); |
81d68a96 | 147 | start_critical_timings(); |
a15da49d AK |
148 | /* In many cases the interrupt that ended idle |
149 | has already called exit_idle. But some idle | |
150 | loops can be woken up without interrupt. */ | |
95833c83 | 151 | __exit_idle(); |
1da177e4 LT |
152 | } |
153 | ||
02290683 | 154 | tick_nohz_restart_sched_tick(); |
5bfb5d69 | 155 | preempt_enable_no_resched(); |
1da177e4 | 156 | schedule(); |
5bfb5d69 | 157 | preempt_disable(); |
1da177e4 LT |
158 | } |
159 | } | |
160 | ||
6612538c | 161 | /* Prints also some state that isn't saved in the pt_regs */ |
e2ce07c8 | 162 | void __show_regs(struct pt_regs *regs, int all) |
1da177e4 LT |
163 | { |
164 | unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L, fs, gs, shadowgs; | |
bb1995d5 | 165 | unsigned long d0, d1, d2, d3, d6, d7; |
6612538c HS |
166 | unsigned int fsindex, gsindex; |
167 | unsigned int ds, cs, es; | |
48ec4d95 | 168 | const char *board; |
1da177e4 LT |
169 | |
170 | printk("\n"); | |
171 | print_modules(); | |
48ec4d95 KM |
172 | board = dmi_get_system_info(DMI_PRODUCT_NAME); |
173 | if (!board) | |
174 | board = ""; | |
175 | printk(KERN_INFO "Pid: %d, comm: %.20s %s %s %.*s %s\n", | |
9acf23c4 | 176 | current->pid, current->comm, print_tainted(), |
96b644bd SH |
177 | init_utsname()->release, |
178 | (int)strcspn(init_utsname()->version, " "), | |
48ec4d95 | 179 | init_utsname()->version, board); |
8092c654 | 180 | printk(KERN_INFO "RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->ip); |
aafbd7eb | 181 | printk_address(regs->ip, 1); |
8092c654 GP |
182 | printk(KERN_INFO "RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, |
183 | regs->sp, regs->flags); | |
184 | printk(KERN_INFO "RAX: %016lx RBX: %016lx RCX: %016lx\n", | |
65ea5b03 | 185 | regs->ax, regs->bx, regs->cx); |
8092c654 | 186 | printk(KERN_INFO "RDX: %016lx RSI: %016lx RDI: %016lx\n", |
65ea5b03 | 187 | regs->dx, regs->si, regs->di); |
8092c654 | 188 | printk(KERN_INFO "RBP: %016lx R08: %016lx R09: %016lx\n", |
65ea5b03 | 189 | regs->bp, regs->r8, regs->r9); |
8092c654 | 190 | printk(KERN_INFO "R10: %016lx R11: %016lx R12: %016lx\n", |
7de08b4e | 191 | regs->r10, regs->r11, regs->r12); |
8092c654 | 192 | printk(KERN_INFO "R13: %016lx R14: %016lx R15: %016lx\n", |
7de08b4e | 193 | regs->r13, regs->r14, regs->r15); |
1da177e4 | 194 | |
7de08b4e GP |
195 | asm("movl %%ds,%0" : "=r" (ds)); |
196 | asm("movl %%cs,%0" : "=r" (cs)); | |
197 | asm("movl %%es,%0" : "=r" (es)); | |
1da177e4 LT |
198 | asm("movl %%fs,%0" : "=r" (fsindex)); |
199 | asm("movl %%gs,%0" : "=r" (gsindex)); | |
200 | ||
201 | rdmsrl(MSR_FS_BASE, fs); | |
7de08b4e GP |
202 | rdmsrl(MSR_GS_BASE, gs); |
203 | rdmsrl(MSR_KERNEL_GS_BASE, shadowgs); | |
1da177e4 | 204 | |
e2ce07c8 PE |
205 | if (!all) |
206 | return; | |
1da177e4 | 207 | |
f51c9452 GOC |
208 | cr0 = read_cr0(); |
209 | cr2 = read_cr2(); | |
210 | cr3 = read_cr3(); | |
211 | cr4 = read_cr4(); | |
1da177e4 | 212 | |
8092c654 | 213 | printk(KERN_INFO "FS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n", |
7de08b4e | 214 | fs, fsindex, gs, gsindex, shadowgs); |
8092c654 GP |
215 | printk(KERN_INFO "CS: %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds, |
216 | es, cr0); | |
217 | printk(KERN_INFO "CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3, | |
218 | cr4); | |
bb1995d5 AS |
219 | |
220 | get_debugreg(d0, 0); | |
221 | get_debugreg(d1, 1); | |
222 | get_debugreg(d2, 2); | |
8092c654 | 223 | printk(KERN_INFO "DR0: %016lx DR1: %016lx DR2: %016lx\n", d0, d1, d2); |
bb1995d5 AS |
224 | get_debugreg(d3, 3); |
225 | get_debugreg(d6, 6); | |
226 | get_debugreg(d7, 7); | |
8092c654 | 227 | printk(KERN_INFO "DR3: %016lx DR6: %016lx DR7: %016lx\n", d3, d6, d7); |
1da177e4 LT |
228 | } |
229 | ||
230 | void show_regs(struct pt_regs *regs) | |
231 | { | |
8092c654 | 232 | printk(KERN_INFO "CPU %d:", smp_processor_id()); |
e2ce07c8 | 233 | __show_regs(regs, 1); |
bc850d6b | 234 | show_trace(NULL, regs, (void *)(regs + 1), regs->bp); |
1da177e4 LT |
235 | } |
236 | ||
1da177e4 LT |
237 | void release_thread(struct task_struct *dead_task) |
238 | { | |
239 | if (dead_task->mm) { | |
240 | if (dead_task->mm->context.size) { | |
241 | printk("WARNING: dead process %8s still has LDT? <%p/%d>\n", | |
242 | dead_task->comm, | |
243 | dead_task->mm->context.ldt, | |
244 | dead_task->mm->context.size); | |
245 | BUG(); | |
246 | } | |
247 | } | |
248 | } | |
249 | ||
250 | static inline void set_32bit_tls(struct task_struct *t, int tls, u32 addr) | |
251 | { | |
6612538c | 252 | struct user_desc ud = { |
1da177e4 LT |
253 | .base_addr = addr, |
254 | .limit = 0xfffff, | |
255 | .seg_32bit = 1, | |
256 | .limit_in_pages = 1, | |
257 | .useable = 1, | |
258 | }; | |
ade1af77 | 259 | struct desc_struct *desc = t->thread.tls_array; |
1da177e4 | 260 | desc += tls; |
80fbb69a | 261 | fill_ldt(desc, &ud); |
1da177e4 LT |
262 | } |
263 | ||
264 | static inline u32 read_32bit_tls(struct task_struct *t, int tls) | |
265 | { | |
91394eb0 | 266 | return get_desc_base(&t->thread.tls_array[tls]); |
1da177e4 LT |
267 | } |
268 | ||
269 | /* | |
270 | * This gets called before we allocate a new thread and copy | |
271 | * the current task into it. | |
272 | */ | |
273 | void prepare_to_copy(struct task_struct *tsk) | |
274 | { | |
275 | unlazy_fpu(tsk); | |
276 | } | |
277 | ||
6f2c55b8 | 278 | int copy_thread(unsigned long clone_flags, unsigned long sp, |
1da177e4 | 279 | unsigned long unused, |
7de08b4e | 280 | struct task_struct *p, struct pt_regs *regs) |
1da177e4 LT |
281 | { |
282 | int err; | |
7de08b4e | 283 | struct pt_regs *childregs; |
1da177e4 LT |
284 | struct task_struct *me = current; |
285 | ||
a88cde13 | 286 | childregs = ((struct pt_regs *) |
57eafdc2 | 287 | (THREAD_SIZE + task_stack_page(p))) - 1; |
1da177e4 LT |
288 | *childregs = *regs; |
289 | ||
65ea5b03 PA |
290 | childregs->ax = 0; |
291 | childregs->sp = sp; | |
292 | if (sp == ~0UL) | |
293 | childregs->sp = (unsigned long)childregs; | |
1da177e4 | 294 | |
faca6227 PA |
295 | p->thread.sp = (unsigned long) childregs; |
296 | p->thread.sp0 = (unsigned long) (childregs+1); | |
297 | p->thread.usersp = me->thread.usersp; | |
1da177e4 | 298 | |
e4f17c43 | 299 | set_tsk_thread_flag(p, TIF_FORK); |
1da177e4 LT |
300 | |
301 | p->thread.fs = me->thread.fs; | |
302 | p->thread.gs = me->thread.gs; | |
303 | ||
ada85708 JF |
304 | savesegment(gs, p->thread.gsindex); |
305 | savesegment(fs, p->thread.fsindex); | |
306 | savesegment(es, p->thread.es); | |
307 | savesegment(ds, p->thread.ds); | |
1da177e4 | 308 | |
d3a4f48d | 309 | if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) { |
1da177e4 LT |
310 | p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL); |
311 | if (!p->thread.io_bitmap_ptr) { | |
312 | p->thread.io_bitmap_max = 0; | |
313 | return -ENOMEM; | |
314 | } | |
a88cde13 AK |
315 | memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr, |
316 | IO_BITMAP_BYTES); | |
d3a4f48d | 317 | set_tsk_thread_flag(p, TIF_IO_BITMAP); |
6612538c | 318 | } |
1da177e4 LT |
319 | |
320 | /* | |
321 | * Set a new TLS for the child thread? | |
322 | */ | |
323 | if (clone_flags & CLONE_SETTLS) { | |
324 | #ifdef CONFIG_IA32_EMULATION | |
325 | if (test_thread_flag(TIF_IA32)) | |
efd1ca52 | 326 | err = do_set_thread_area(p, -1, |
65ea5b03 | 327 | (struct user_desc __user *)childregs->si, 0); |
7de08b4e GP |
328 | else |
329 | #endif | |
330 | err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8); | |
331 | if (err) | |
1da177e4 LT |
332 | goto out; |
333 | } | |
bf53de90 MM |
334 | |
335 | ds_copy_thread(p, me); | |
336 | ||
337 | clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR); | |
338 | p->thread.debugctlmsr = 0; | |
339 | ||
1da177e4 LT |
340 | err = 0; |
341 | out: | |
342 | if (err && p->thread.io_bitmap_ptr) { | |
343 | kfree(p->thread.io_bitmap_ptr); | |
344 | p->thread.io_bitmap_max = 0; | |
345 | } | |
346 | return err; | |
347 | } | |
348 | ||
513ad84b IM |
349 | void |
350 | start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) | |
351 | { | |
ada85708 JF |
352 | loadsegment(fs, 0); |
353 | loadsegment(es, 0); | |
354 | loadsegment(ds, 0); | |
513ad84b IM |
355 | load_gs_index(0); |
356 | regs->ip = new_ip; | |
357 | regs->sp = new_sp; | |
3d1e42a7 | 358 | percpu_write(old_rsp, new_sp); |
513ad84b IM |
359 | regs->cs = __USER_CS; |
360 | regs->ss = __USER_DS; | |
361 | regs->flags = 0x200; | |
362 | set_fs(USER_DS); | |
aa283f49 SS |
363 | /* |
364 | * Free the old FP and other extended state | |
365 | */ | |
366 | free_thread_xstate(current); | |
513ad84b IM |
367 | } |
368 | EXPORT_SYMBOL_GPL(start_thread); | |
369 | ||
1da177e4 LT |
370 | /* |
371 | * switch_to(x,y) should switch tasks from x to y. | |
372 | * | |
6612538c | 373 | * This could still be optimized: |
1da177e4 LT |
374 | * - fold all the options into a flag word and test it with a single test. |
375 | * - could test fs/gs bitsliced | |
099f318b AK |
376 | * |
377 | * Kprobes not supported here. Set the probe on schedule instead. | |
8b96f011 | 378 | * Function graph tracer not supported too. |
1da177e4 | 379 | */ |
8b96f011 | 380 | __notrace_funcgraph struct task_struct * |
a88cde13 | 381 | __switch_to(struct task_struct *prev_p, struct task_struct *next_p) |
1da177e4 | 382 | { |
87b935a0 JF |
383 | struct thread_struct *prev = &prev_p->thread; |
384 | struct thread_struct *next = &next_p->thread; | |
6612538c | 385 | int cpu = smp_processor_id(); |
1da177e4 | 386 | struct tss_struct *tss = &per_cpu(init_tss, cpu); |
478de5a9 | 387 | unsigned fsindex, gsindex; |
1da177e4 | 388 | |
e07e23e1 | 389 | /* we're going to use this soon, after a few expensive things */ |
7de08b4e | 390 | if (next_p->fpu_counter > 5) |
61c4628b | 391 | prefetch(next->xstate); |
e07e23e1 | 392 | |
1da177e4 LT |
393 | /* |
394 | * Reload esp0, LDT and the page table pointer: | |
395 | */ | |
7818a1e0 | 396 | load_sp0(tss, next); |
1da177e4 | 397 | |
7de08b4e | 398 | /* |
1da177e4 LT |
399 | * Switch DS and ES. |
400 | * This won't pick up thread selector changes, but I guess that is ok. | |
401 | */ | |
ada85708 | 402 | savesegment(es, prev->es); |
1da177e4 | 403 | if (unlikely(next->es | prev->es)) |
7de08b4e | 404 | loadsegment(es, next->es); |
ada85708 JF |
405 | |
406 | savesegment(ds, prev->ds); | |
1da177e4 LT |
407 | if (unlikely(next->ds | prev->ds)) |
408 | loadsegment(ds, next->ds); | |
409 | ||
478de5a9 JF |
410 | |
411 | /* We must save %fs and %gs before load_TLS() because | |
412 | * %fs and %gs may be cleared by load_TLS(). | |
413 | * | |
414 | * (e.g. xen_load_tls()) | |
415 | */ | |
416 | savesegment(fs, fsindex); | |
417 | savesegment(gs, gsindex); | |
418 | ||
1da177e4 LT |
419 | load_TLS(next, cpu); |
420 | ||
3fe0a63e JF |
421 | /* |
422 | * Leave lazy mode, flushing any hypercalls made here. | |
423 | * This must be done before restoring TLS segments so | |
424 | * the GDT and LDT are properly updated, and must be | |
425 | * done before math_state_restore, so the TS bit is up | |
426 | * to date. | |
427 | */ | |
428 | arch_leave_lazy_cpu_mode(); | |
429 | ||
7de08b4e | 430 | /* |
1da177e4 | 431 | * Switch FS and GS. |
87b935a0 JF |
432 | * |
433 | * Segment register != 0 always requires a reload. Also | |
434 | * reload when it has changed. When prev process used 64bit | |
435 | * base always reload to avoid an information leak. | |
1da177e4 | 436 | */ |
87b935a0 JF |
437 | if (unlikely(fsindex | next->fsindex | prev->fs)) { |
438 | loadsegment(fs, next->fsindex); | |
7de08b4e | 439 | /* |
87b935a0 JF |
440 | * Check if the user used a selector != 0; if yes |
441 | * clear 64bit base, since overloaded base is always | |
442 | * mapped to the Null selector | |
443 | */ | |
444 | if (fsindex) | |
7de08b4e | 445 | prev->fs = 0; |
1da177e4 | 446 | } |
87b935a0 JF |
447 | /* when next process has a 64bit base use it */ |
448 | if (next->fs) | |
449 | wrmsrl(MSR_FS_BASE, next->fs); | |
450 | prev->fsindex = fsindex; | |
451 | ||
452 | if (unlikely(gsindex | next->gsindex | prev->gs)) { | |
453 | load_gs_index(next->gsindex); | |
454 | if (gsindex) | |
7de08b4e | 455 | prev->gs = 0; |
1da177e4 | 456 | } |
87b935a0 JF |
457 | if (next->gs) |
458 | wrmsrl(MSR_KERNEL_GS_BASE, next->gs); | |
459 | prev->gsindex = gsindex; | |
1da177e4 | 460 | |
0a5ace2a AK |
461 | /* Must be after DS reload */ |
462 | unlazy_fpu(prev_p); | |
463 | ||
7de08b4e | 464 | /* |
45948d77 | 465 | * Switch the PDA and FPU contexts. |
1da177e4 | 466 | */ |
3d1e42a7 BG |
467 | prev->usersp = percpu_read(old_rsp); |
468 | percpu_write(old_rsp, next->usersp); | |
c6f5e0ac | 469 | percpu_write(current_task, next_p); |
18bd057b | 470 | |
9af45651 | 471 | percpu_write(kernel_stack, |
87b935a0 | 472 | (unsigned long)task_stack_page(next_p) + |
9af45651 | 473 | THREAD_SIZE - KERNEL_STACK_OFFSET); |
1da177e4 LT |
474 | |
475 | /* | |
d3a4f48d | 476 | * Now maybe reload the debug registers and handle I/O bitmaps |
1da177e4 | 477 | */ |
eee3af4a MM |
478 | if (unlikely(task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT || |
479 | task_thread_info(prev_p)->flags & _TIF_WORK_CTXSW_PREV)) | |
d3a4f48d | 480 | __switch_to_xtra(prev_p, next_p, tss); |
1da177e4 | 481 | |
e07e23e1 AV |
482 | /* If the task has used fpu the last 5 timeslices, just do a full |
483 | * restore of the math state immediately to avoid the trap; the | |
484 | * chances of needing FPU soon are obviously high now | |
870568b3 SS |
485 | * |
486 | * tsk_used_math() checks prevent calling math_state_restore(), | |
487 | * which can sleep in the case of !tsk_used_math() | |
e07e23e1 | 488 | */ |
870568b3 | 489 | if (tsk_used_math(next_p) && next_p->fpu_counter > 5) |
e07e23e1 | 490 | math_state_restore(); |
1da177e4 LT |
491 | return prev_p; |
492 | } | |
493 | ||
494 | /* | |
495 | * sys_execve() executes a new program. | |
496 | */ | |
6612538c | 497 | asmlinkage |
1da177e4 | 498 | long sys_execve(char __user *name, char __user * __user *argv, |
5d119b2c | 499 | char __user * __user *envp, struct pt_regs *regs) |
1da177e4 LT |
500 | { |
501 | long error; | |
7de08b4e | 502 | char *filename; |
1da177e4 LT |
503 | |
504 | filename = getname(name); | |
505 | error = PTR_ERR(filename); | |
5d119b2c | 506 | if (IS_ERR(filename)) |
1da177e4 | 507 | return error; |
5d119b2c | 508 | error = do_execve(filename, argv, envp, regs); |
1da177e4 LT |
509 | putname(filename); |
510 | return error; | |
511 | } | |
512 | ||
513 | void set_personality_64bit(void) | |
514 | { | |
515 | /* inherit personality from parent */ | |
516 | ||
517 | /* Make sure to be in 64bit mode */ | |
6612538c | 518 | clear_thread_flag(TIF_IA32); |
1da177e4 LT |
519 | |
520 | /* TBD: overwrites user setup. Should have two bits. | |
521 | But 64bit processes have always behaved this way, | |
522 | so it's not too bad. The main problem is just that | |
6612538c | 523 | 32bit childs are affected again. */ |
1da177e4 LT |
524 | current->personality &= ~READ_IMPLIES_EXEC; |
525 | } | |
526 | ||
a88cde13 AK |
527 | asmlinkage long |
528 | sys_clone(unsigned long clone_flags, unsigned long newsp, | |
529 | void __user *parent_tid, void __user *child_tid, struct pt_regs *regs) | |
1da177e4 LT |
530 | { |
531 | if (!newsp) | |
65ea5b03 | 532 | newsp = regs->sp; |
1da177e4 LT |
533 | return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid); |
534 | } | |
535 | ||
1da177e4 LT |
536 | unsigned long get_wchan(struct task_struct *p) |
537 | { | |
538 | unsigned long stack; | |
7de08b4e | 539 | u64 fp, ip; |
1da177e4 LT |
540 | int count = 0; |
541 | ||
7de08b4e GP |
542 | if (!p || p == current || p->state == TASK_RUNNING) |
543 | return 0; | |
57eafdc2 | 544 | stack = (unsigned long)task_stack_page(p); |
e1e23bb0 | 545 | if (p->thread.sp < stack || p->thread.sp >= stack+THREAD_SIZE) |
1da177e4 | 546 | return 0; |
faca6227 | 547 | fp = *(u64 *)(p->thread.sp); |
7de08b4e | 548 | do { |
a88cde13 | 549 | if (fp < (unsigned long)stack || |
e1e23bb0 | 550 | fp >= (unsigned long)stack+THREAD_SIZE) |
7de08b4e | 551 | return 0; |
65ea5b03 PA |
552 | ip = *(u64 *)(fp+8); |
553 | if (!in_sched_functions(ip)) | |
554 | return ip; | |
7de08b4e GP |
555 | fp = *(u64 *)fp; |
556 | } while (count++ < 16); | |
1da177e4 LT |
557 | return 0; |
558 | } | |
559 | ||
560 | long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) | |
7de08b4e GP |
561 | { |
562 | int ret = 0; | |
1da177e4 LT |
563 | int doit = task == current; |
564 | int cpu; | |
565 | ||
7de08b4e | 566 | switch (code) { |
1da177e4 | 567 | case ARCH_SET_GS: |
84929801 | 568 | if (addr >= TASK_SIZE_OF(task)) |
7de08b4e | 569 | return -EPERM; |
1da177e4 | 570 | cpu = get_cpu(); |
7de08b4e | 571 | /* handle small bases via the GDT because that's faster to |
1da177e4 | 572 | switch. */ |
7de08b4e GP |
573 | if (addr <= 0xffffffff) { |
574 | set_32bit_tls(task, GS_TLS, addr); | |
575 | if (doit) { | |
1da177e4 | 576 | load_TLS(&task->thread, cpu); |
7de08b4e | 577 | load_gs_index(GS_TLS_SEL); |
1da177e4 | 578 | } |
7de08b4e | 579 | task->thread.gsindex = GS_TLS_SEL; |
1da177e4 | 580 | task->thread.gs = 0; |
7de08b4e | 581 | } else { |
1da177e4 LT |
582 | task->thread.gsindex = 0; |
583 | task->thread.gs = addr; | |
584 | if (doit) { | |
a88cde13 AK |
585 | load_gs_index(0); |
586 | ret = checking_wrmsrl(MSR_KERNEL_GS_BASE, addr); | |
7de08b4e | 587 | } |
1da177e4 LT |
588 | } |
589 | put_cpu(); | |
590 | break; | |
591 | case ARCH_SET_FS: | |
592 | /* Not strictly needed for fs, but do it for symmetry | |
593 | with gs */ | |
84929801 | 594 | if (addr >= TASK_SIZE_OF(task)) |
6612538c | 595 | return -EPERM; |
1da177e4 | 596 | cpu = get_cpu(); |
6612538c | 597 | /* handle small bases via the GDT because that's faster to |
1da177e4 | 598 | switch. */ |
6612538c | 599 | if (addr <= 0xffffffff) { |
1da177e4 | 600 | set_32bit_tls(task, FS_TLS, addr); |
6612538c HS |
601 | if (doit) { |
602 | load_TLS(&task->thread, cpu); | |
ada85708 | 603 | loadsegment(fs, FS_TLS_SEL); |
1da177e4 LT |
604 | } |
605 | task->thread.fsindex = FS_TLS_SEL; | |
606 | task->thread.fs = 0; | |
6612538c | 607 | } else { |
1da177e4 LT |
608 | task->thread.fsindex = 0; |
609 | task->thread.fs = addr; | |
610 | if (doit) { | |
611 | /* set the selector to 0 to not confuse | |
612 | __switch_to */ | |
ada85708 | 613 | loadsegment(fs, 0); |
a88cde13 | 614 | ret = checking_wrmsrl(MSR_FS_BASE, addr); |
1da177e4 LT |
615 | } |
616 | } | |
617 | put_cpu(); | |
618 | break; | |
6612538c HS |
619 | case ARCH_GET_FS: { |
620 | unsigned long base; | |
1da177e4 LT |
621 | if (task->thread.fsindex == FS_TLS_SEL) |
622 | base = read_32bit_tls(task, FS_TLS); | |
a88cde13 | 623 | else if (doit) |
1da177e4 | 624 | rdmsrl(MSR_FS_BASE, base); |
a88cde13 | 625 | else |
1da177e4 | 626 | base = task->thread.fs; |
6612538c HS |
627 | ret = put_user(base, (unsigned long __user *)addr); |
628 | break; | |
1da177e4 | 629 | } |
6612538c | 630 | case ARCH_GET_GS: { |
1da177e4 | 631 | unsigned long base; |
97c2803c | 632 | unsigned gsindex; |
1da177e4 LT |
633 | if (task->thread.gsindex == GS_TLS_SEL) |
634 | base = read_32bit_tls(task, GS_TLS); | |
97c2803c | 635 | else if (doit) { |
ada85708 | 636 | savesegment(gs, gsindex); |
97c2803c JB |
637 | if (gsindex) |
638 | rdmsrl(MSR_KERNEL_GS_BASE, base); | |
639 | else | |
640 | base = task->thread.gs; | |
7de08b4e | 641 | } else |
1da177e4 | 642 | base = task->thread.gs; |
6612538c | 643 | ret = put_user(base, (unsigned long __user *)addr); |
1da177e4 LT |
644 | break; |
645 | } | |
646 | ||
647 | default: | |
648 | ret = -EINVAL; | |
649 | break; | |
6612538c | 650 | } |
1da177e4 | 651 | |
6612538c HS |
652 | return ret; |
653 | } | |
1da177e4 LT |
654 | |
655 | long sys_arch_prctl(int code, unsigned long addr) | |
656 | { | |
657 | return do_arch_prctl(current, code, addr); | |
1da177e4 LT |
658 | } |
659 |