1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Kernel Probes (KProbes)
4 * arch/ia64/kernel/kprobes.c
6 * Copyright (C) IBM Corporation, 2002, 2004
7 * Copyright (C) Intel Corporation, 2005
9 * 2005-Apr Rusty Lynch <rusty.lynch@intel.com> and Anil S Keshavamurthy
10 * <anil.s.keshavamurthy@intel.com> adapted from i386
13 #include <linux/kprobes.h>
14 #include <linux/ptrace.h>
15 #include <linux/string.h>
16 #include <linux/slab.h>
17 #include <linux/preempt.h>
18 #include <linux/extable.h>
19 #include <linux/kdebug.h>
20 #include <linux/pgtable.h>
22 #include <asm/sections.h>
23 #include <asm/exception.h>
25 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
26 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
28 struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}};
30 enum instruction_type {A, I, M, F, B, L, X, u};
31 static enum instruction_type bundle_encoding[32][3] = {
66 /* Insert a long branch code */
67 static void __kprobes set_brl_inst(void *from, void *to)
69 s64 rel = ((s64) to - (s64) from) >> 4;
71 brl = (bundle_t *) ((u64) from & ~0xf);
72 brl->quad0.template = 0x05; /* [MLX](stop) */
73 brl->quad0.slot0 = NOP_M_INST; /* nop.m 0x0 */
74 brl->quad0.slot1_p0 = ((rel >> 20) & 0x7fffffffff) << 2;
75 brl->quad1.slot1_p1 = (((rel >> 20) & 0x7fffffffff) << 2) >> (64 - 46);
76 /* brl.cond.sptk.many.clr rel<<4 (qp=0) */
77 brl->quad1.slot2 = BRL_INST(rel >> 59, rel & 0xfffff);
81 * In this function we check to see if the instruction
82 * is IP relative instruction and update the kprobe
83 * inst flag accordingly
85 static void __kprobes update_kprobe_inst_flag(uint template, uint slot,
87 unsigned long kprobe_inst,
90 p->ainsn.inst_flag = 0;
91 p->ainsn.target_br_reg = 0;
94 /* Check for Break instruction
95 * Bits 37:40 Major opcode to be zero
96 * Bits 27:32 X6 to be zero
97 * Bits 32:35 X3 to be zero
99 if ((!major_opcode) && (!((kprobe_inst >> 27) & 0x1FF)) ) {
100 /* is a break instruction */
101 p->ainsn.inst_flag |= INST_FLAG_BREAK_INST;
105 if (bundle_encoding[template][slot] == B) {
106 switch (major_opcode) {
107 case INDIRECT_CALL_OPCODE:
108 p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
109 p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
111 case IP_RELATIVE_PREDICT_OPCODE:
112 case IP_RELATIVE_BRANCH_OPCODE:
113 p->ainsn.inst_flag |= INST_FLAG_FIX_RELATIVE_IP_ADDR;
115 case IP_RELATIVE_CALL_OPCODE:
116 p->ainsn.inst_flag |= INST_FLAG_FIX_RELATIVE_IP_ADDR;
117 p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
118 p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
121 } else if (bundle_encoding[template][slot] == X) {
122 switch (major_opcode) {
123 case LONG_CALL_OPCODE:
124 p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
125 p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
133 * In this function we check to see if the instruction
134 * (qp) cmpx.crel.ctype p1,p2=r2,r3
135 * on which we are inserting kprobe is cmp instruction
138 static uint __kprobes is_cmp_ctype_unc_inst(uint template, uint slot,
140 unsigned long kprobe_inst)
145 if (!((bundle_encoding[template][slot] == I) ||
146 (bundle_encoding[template][slot] == M)))
149 if (!((major_opcode == 0xC) || (major_opcode == 0xD) ||
150 (major_opcode == 0xE)))
153 cmp_inst.l = kprobe_inst;
154 if ((cmp_inst.f.x2 == 0) || (cmp_inst.f.x2 == 1)) {
155 /* Integer compare - Register Register (A6 type)*/
156 if ((cmp_inst.f.tb == 0) && (cmp_inst.f.ta == 0)
157 &&(cmp_inst.f.c == 1))
159 } else if ((cmp_inst.f.x2 == 2)||(cmp_inst.f.x2 == 3)) {
160 /* Integer compare - Immediate Register (A8 type)*/
161 if ((cmp_inst.f.ta == 0) &&(cmp_inst.f.c == 1))
169 * In this function we check to see if the instruction
170 * on which we are inserting kprobe is supported.
171 * Returns qp value if supported
172 * Returns -EINVAL if unsupported
174 static int __kprobes unsupported_inst(uint template, uint slot,
176 unsigned long kprobe_inst,
181 qp = kprobe_inst & 0x3f;
182 if (is_cmp_ctype_unc_inst(template, slot, major_opcode, kprobe_inst)) {
183 if (slot == 1 && qp) {
184 printk(KERN_WARNING "Kprobes on cmp unc "
185 "instruction on slot 1 at <0x%lx> "
186 "is not supported\n", addr);
192 else if (bundle_encoding[template][slot] == I) {
193 if (major_opcode == 0) {
195 * Check for Integer speculation instruction
196 * - Bit 33-35 to be equal to 0x1
198 if (((kprobe_inst >> 33) & 0x7) == 1) {
200 "Kprobes on speculation inst at <0x%lx> not supported\n",
205 * IP relative mov instruction
206 * - Bit 27-35 to be equal to 0x30
208 if (((kprobe_inst >> 27) & 0x1FF) == 0x30) {
210 "Kprobes on \"mov r1=ip\" at <0x%lx> not supported\n",
216 else if ((major_opcode == 5) && !(kprobe_inst & (0xFUl << 33)) &&
217 (kprobe_inst & (0x1UL << 12))) {
218 /* test bit instructions, tbit,tnat,tf
219 * bit 33-36 to be equal to 0
220 * bit 12 to be equal to 1
222 if (slot == 1 && qp) {
223 printk(KERN_WARNING "Kprobes on test bit "
224 "instruction on slot at <0x%lx> "
225 "is not supported\n", addr);
231 else if (bundle_encoding[template][slot] == B) {
232 if (major_opcode == 7) {
233 /* IP-Relative Predict major code is 7 */
234 printk(KERN_WARNING "Kprobes on IP-Relative"
235 "Predict is not supported\n");
238 else if (major_opcode == 2) {
239 /* Indirect Predict, major code is 2
240 * bit 27-32 to be equal to 10 or 11
242 int x6=(kprobe_inst >> 27) & 0x3F;
243 if ((x6 == 0x10) || (x6 == 0x11)) {
244 printk(KERN_WARNING "Kprobes on "
245 "Indirect Predict is not supported\n");
250 /* kernel does not use float instruction, here for safety kprobe
251 * will judge whether it is fcmp/flass/float approximation instruction
253 else if (unlikely(bundle_encoding[template][slot] == F)) {
254 if ((major_opcode == 4 || major_opcode == 5) &&
255 (kprobe_inst & (0x1 << 12))) {
256 /* fcmp/fclass unc instruction */
257 if (slot == 1 && qp) {
258 printk(KERN_WARNING "Kprobes on fcmp/fclass "
259 "instruction on slot at <0x%lx> "
260 "is not supported\n", addr);
266 if ((major_opcode == 0 || major_opcode == 1) &&
267 (kprobe_inst & (0x1UL << 33))) {
268 /* float Approximation instruction */
269 if (slot == 1 && qp) {
270 printk(KERN_WARNING "Kprobes on float Approx "
271 "instr at <0x%lx> is not supported\n",
282 * In this function we override the bundle with
283 * the break instruction at the given slot.
285 static void __kprobes prepare_break_inst(uint template, uint slot,
287 unsigned long kprobe_inst,
291 unsigned long break_inst = BREAK_INST;
292 bundle_t *bundle = &p->opcode.bundle;
295 * Copy the original kprobe_inst qualifying predicate(qp)
296 * to the break instruction
302 bundle->quad0.slot0 = break_inst;
305 bundle->quad0.slot1_p0 = break_inst;
306 bundle->quad1.slot1_p1 = break_inst >> (64-46);
309 bundle->quad1.slot2 = break_inst;
314 * Update the instruction flag, so that we can
315 * emulate the instruction properly after we
316 * single step on original instruction
318 update_kprobe_inst_flag(template, slot, major_opcode, kprobe_inst, p);
321 static void __kprobes get_kprobe_inst(bundle_t *bundle, uint slot,
322 unsigned long *kprobe_inst, uint *major_opcode)
324 unsigned long kprobe_inst_p0, kprobe_inst_p1;
325 unsigned int template;
327 template = bundle->quad0.template;
331 *major_opcode = (bundle->quad0.slot0 >> SLOT0_OPCODE_SHIFT);
332 *kprobe_inst = bundle->quad0.slot0;
335 *major_opcode = (bundle->quad1.slot1_p1 >> SLOT1_p1_OPCODE_SHIFT);
336 kprobe_inst_p0 = bundle->quad0.slot1_p0;
337 kprobe_inst_p1 = bundle->quad1.slot1_p1;
338 *kprobe_inst = kprobe_inst_p0 | (kprobe_inst_p1 << (64-46));
341 *major_opcode = (bundle->quad1.slot2 >> SLOT2_OPCODE_SHIFT);
342 *kprobe_inst = bundle->quad1.slot2;
347 /* Returns non-zero if the addr is in the Interrupt Vector Table */
348 static int __kprobes in_ivt_functions(unsigned long addr)
350 return (addr >= (unsigned long)__start_ivt_text
351 && addr < (unsigned long)__end_ivt_text);
354 static int __kprobes valid_kprobe_addr(int template, int slot,
357 if ((slot > 2) || ((bundle_encoding[template][1] == L) && slot > 1)) {
358 printk(KERN_WARNING "Attempting to insert unaligned kprobe "
363 if (in_ivt_functions(addr)) {
364 printk(KERN_WARNING "Kprobes can't be inserted inside "
365 "IVT functions at 0x%lx\n", addr);
372 static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb)
375 i = atomic_add_return(1, &kcb->prev_kprobe_index);
376 kcb->prev_kprobe[i-1].kp = kprobe_running();
377 kcb->prev_kprobe[i-1].status = kcb->kprobe_status;
380 static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
383 i = atomic_read(&kcb->prev_kprobe_index);
384 __this_cpu_write(current_kprobe, kcb->prev_kprobe[i-1].kp);
385 kcb->kprobe_status = kcb->prev_kprobe[i-1].status;
386 atomic_sub(1, &kcb->prev_kprobe_index);
389 static void __kprobes set_current_kprobe(struct kprobe *p,
390 struct kprobe_ctlblk *kcb)
392 __this_cpu_write(current_kprobe, p);
395 static void kretprobe_trampoline(void)
399 int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
401 regs->cr_iip = __kretprobe_trampoline_handler(regs,
402 dereference_function_descriptor(kretprobe_trampoline), NULL);
404 * By returning a non-zero value, we are telling
405 * kprobe_handler() that we don't want the post_handler
406 * to run (and have re-enabled preemption)
411 void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
412 struct pt_regs *regs)
414 ri->ret_addr = (kprobe_opcode_t *)regs->b0;
417 /* Replace the return addr with trampoline addr */
418 regs->b0 = (unsigned long)dereference_function_descriptor(kretprobe_trampoline);
421 /* Check the instruction in the slot is break */
422 static int __kprobes __is_ia64_break_inst(bundle_t *bundle, uint slot)
424 unsigned int major_opcode;
425 unsigned int template = bundle->quad0.template;
426 unsigned long kprobe_inst;
428 /* Move to slot 2, if bundle is MLX type and kprobe slot is 1 */
429 if (slot == 1 && bundle_encoding[template][1] == L)
432 /* Get Kprobe probe instruction at given slot*/
433 get_kprobe_inst(bundle, slot, &kprobe_inst, &major_opcode);
435 /* For break instruction,
436 * Bits 37:40 Major opcode to be zero
437 * Bits 27:32 X6 to be zero
438 * Bits 32:35 X3 to be zero
440 if (major_opcode || ((kprobe_inst >> 27) & 0x1FF)) {
441 /* Not a break instruction */
445 /* Is a break instruction */
450 * In this function, we check whether the target bundle modifies IP or
451 * it triggers an exception. If so, it cannot be boostable.
453 static int __kprobes can_boost(bundle_t *bundle, uint slot,
454 unsigned long bundle_addr)
456 unsigned int template = bundle->quad0.template;
459 if (search_exception_tables(bundle_addr + slot) ||
460 __is_ia64_break_inst(bundle, slot))
461 return 0; /* exception may occur in this bundle*/
462 } while ((++slot) < 3);
464 if (template >= 0x10 /* including B unit */ ||
465 template == 0x04 /* including X unit */ ||
466 template == 0x06) /* undefined */
472 /* Prepare long jump bundle and disables other boosters if need */
473 static void __kprobes prepare_booster(struct kprobe *p)
475 unsigned long addr = (unsigned long)p->addr & ~0xFULL;
476 unsigned int slot = (unsigned long)p->addr & 0xf;
477 struct kprobe *other_kp;
479 if (can_boost(&p->ainsn.insn[0].bundle, slot, addr)) {
480 set_brl_inst(&p->ainsn.insn[1].bundle, (bundle_t *)addr + 1);
481 p->ainsn.inst_flag |= INST_FLAG_BOOSTABLE;
484 /* disables boosters in previous slots */
485 for (; addr < (unsigned long)p->addr; addr++) {
486 other_kp = get_kprobe((void *)addr);
488 other_kp->ainsn.inst_flag &= ~INST_FLAG_BOOSTABLE;
492 int __kprobes arch_prepare_kprobe(struct kprobe *p)
494 unsigned long addr = (unsigned long) p->addr;
495 unsigned long *kprobe_addr = (unsigned long *)(addr & ~0xFULL);
496 unsigned long kprobe_inst=0;
497 unsigned int slot = addr & 0xf, template, major_opcode = 0;
501 bundle = &((kprobe_opcode_t *)kprobe_addr)->bundle;
502 template = bundle->quad0.template;
504 if(valid_kprobe_addr(template, slot, addr))
507 /* Move to slot 2, if bundle is MLX type and kprobe slot is 1 */
508 if (slot == 1 && bundle_encoding[template][1] == L)
511 /* Get kprobe_inst and major_opcode from the bundle */
512 get_kprobe_inst(bundle, slot, &kprobe_inst, &major_opcode);
514 qp = unsupported_inst(template, slot, major_opcode, kprobe_inst, addr);
518 p->ainsn.insn = get_insn_slot();
521 memcpy(&p->opcode, kprobe_addr, sizeof(kprobe_opcode_t));
522 memcpy(p->ainsn.insn, kprobe_addr, sizeof(kprobe_opcode_t));
524 prepare_break_inst(template, slot, major_opcode, kprobe_inst, p, qp);
531 void __kprobes arch_arm_kprobe(struct kprobe *p)
533 unsigned long arm_addr;
534 bundle_t *src, *dest;
536 arm_addr = ((unsigned long)p->addr) & ~0xFUL;
537 dest = &((kprobe_opcode_t *)arm_addr)->bundle;
538 src = &p->opcode.bundle;
540 flush_icache_range((unsigned long)p->ainsn.insn,
541 (unsigned long)p->ainsn.insn +
542 sizeof(kprobe_opcode_t) * MAX_INSN_SIZE);
544 switch (p->ainsn.slot) {
546 dest->quad0.slot0 = src->quad0.slot0;
549 dest->quad1.slot1_p1 = src->quad1.slot1_p1;
552 dest->quad1.slot2 = src->quad1.slot2;
555 flush_icache_range(arm_addr, arm_addr + sizeof(kprobe_opcode_t));
558 void __kprobes arch_disarm_kprobe(struct kprobe *p)
560 unsigned long arm_addr;
561 bundle_t *src, *dest;
563 arm_addr = ((unsigned long)p->addr) & ~0xFUL;
564 dest = &((kprobe_opcode_t *)arm_addr)->bundle;
565 /* p->ainsn.insn contains the original unaltered kprobe_opcode_t */
566 src = &p->ainsn.insn->bundle;
567 switch (p->ainsn.slot) {
569 dest->quad0.slot0 = src->quad0.slot0;
572 dest->quad1.slot1_p1 = src->quad1.slot1_p1;
575 dest->quad1.slot2 = src->quad1.slot2;
578 flush_icache_range(arm_addr, arm_addr + sizeof(kprobe_opcode_t));
581 void __kprobes arch_remove_kprobe(struct kprobe *p)
584 free_insn_slot(p->ainsn.insn,
585 p->ainsn.inst_flag & INST_FLAG_BOOSTABLE);
586 p->ainsn.insn = NULL;
590 * We are resuming execution after a single step fault, so the pt_regs
591 * structure reflects the register state after we executed the instruction
592 * located in the kprobe (p->ainsn.insn->bundle). We still need to adjust
593 * the ip to point back to the original stack address. To set the IP address
594 * to original stack address, handle the case where we need to fixup the
595 * relative IP address and/or fixup branch register.
597 static void __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs)
599 unsigned long bundle_addr = (unsigned long) (&p->ainsn.insn->bundle);
600 unsigned long resume_addr = (unsigned long)p->addr & ~0xFULL;
601 unsigned long template;
602 int slot = ((unsigned long)p->addr & 0xf);
604 template = p->ainsn.insn->bundle.quad0.template;
606 if (slot == 1 && bundle_encoding[template][1] == L)
609 if (p->ainsn.inst_flag & ~INST_FLAG_BOOSTABLE) {
611 if (p->ainsn.inst_flag & INST_FLAG_FIX_RELATIVE_IP_ADDR) {
612 /* Fix relative IP address */
613 regs->cr_iip = (regs->cr_iip - bundle_addr) +
617 if (p->ainsn.inst_flag & INST_FLAG_FIX_BRANCH_REG) {
619 * Fix target branch register, software convention is
620 * to use either b0 or b6 or b7, so just checking
621 * only those registers
623 switch (p->ainsn.target_br_reg) {
625 if ((regs->b0 == bundle_addr) ||
626 (regs->b0 == bundle_addr + 0x10)) {
627 regs->b0 = (regs->b0 - bundle_addr) +
632 if ((regs->b6 == bundle_addr) ||
633 (regs->b6 == bundle_addr + 0x10)) {
634 regs->b6 = (regs->b6 - bundle_addr) +
639 if ((regs->b7 == bundle_addr) ||
640 (regs->b7 == bundle_addr + 0x10)) {
641 regs->b7 = (regs->b7 - bundle_addr) +
651 if (regs->cr_iip == bundle_addr + 0x10) {
652 regs->cr_iip = resume_addr + 0x10;
655 if (regs->cr_iip == bundle_addr) {
656 regs->cr_iip = resume_addr;
661 /* Turn off Single Step bit */
662 ia64_psr(regs)->ss = 0;
665 static void __kprobes prepare_ss(struct kprobe *p, struct pt_regs *regs)
667 unsigned long bundle_addr = (unsigned long) &p->ainsn.insn->bundle;
668 unsigned long slot = (unsigned long)p->addr & 0xf;
670 /* single step inline if break instruction */
671 if (p->ainsn.inst_flag == INST_FLAG_BREAK_INST)
672 regs->cr_iip = (unsigned long)p->addr & ~0xFULL;
674 regs->cr_iip = bundle_addr & ~0xFULL;
679 ia64_psr(regs)->ri = slot;
681 /* turn on single stepping */
682 ia64_psr(regs)->ss = 1;
685 static int __kprobes is_ia64_break_inst(struct pt_regs *regs)
687 unsigned int slot = ia64_psr(regs)->ri;
688 unsigned long *kprobe_addr = (unsigned long *)regs->cr_iip;
691 memcpy(&bundle, kprobe_addr, sizeof(bundle_t));
693 return __is_ia64_break_inst(&bundle, slot);
696 static int __kprobes pre_kprobes_handler(struct die_args *args)
700 struct pt_regs *regs = args->regs;
701 kprobe_opcode_t *addr = (kprobe_opcode_t *)instruction_pointer(regs);
702 struct kprobe_ctlblk *kcb;
705 * We don't want to be preempted for the entire
706 * duration of kprobe processing
709 kcb = get_kprobe_ctlblk();
711 /* Handle recursion cases */
712 if (kprobe_running()) {
713 p = get_kprobe(addr);
715 if ((kcb->kprobe_status == KPROBE_HIT_SS) &&
716 (p->ainsn.inst_flag == INST_FLAG_BREAK_INST)) {
717 ia64_psr(regs)->ss = 0;
720 /* We have reentered the pre_kprobe_handler(), since
721 * another probe was hit while within the handler.
722 * We here save the original kprobes variables and
723 * just single step on the instruction of the new probe
724 * without calling any user handlers.
726 save_previous_kprobe(kcb);
727 set_current_kprobe(p, kcb);
728 kprobes_inc_nmissed_count(p);
730 kcb->kprobe_status = KPROBE_REENTER;
732 } else if (!is_ia64_break_inst(regs)) {
733 /* The breakpoint instruction was removed by
734 * another cpu right after we hit, no further
735 * handling of this interrupt is appropriate
745 p = get_kprobe(addr);
747 if (!is_ia64_break_inst(regs)) {
749 * The breakpoint instruction was removed right
750 * after we hit it. Another cpu has removed
751 * either a probepoint or a debugger breakpoint
752 * at this address. In either case, no further
753 * handling of this interrupt is appropriate.
759 /* Not one of our break, let kernel handle it */
763 set_current_kprobe(p, kcb);
764 kcb->kprobe_status = KPROBE_HIT_ACTIVE;
766 if (p->pre_handler && p->pre_handler(p, regs)) {
767 reset_current_kprobe();
768 preempt_enable_no_resched();
772 #if !defined(CONFIG_PREEMPTION)
773 if (p->ainsn.inst_flag == INST_FLAG_BOOSTABLE && !p->post_handler) {
774 /* Boost up -- we can execute copied instructions directly */
775 ia64_psr(regs)->ri = p->ainsn.slot;
776 regs->cr_iip = (unsigned long)&p->ainsn.insn->bundle & ~0xFULL;
777 /* turn single stepping off */
778 ia64_psr(regs)->ss = 0;
780 reset_current_kprobe();
781 preempt_enable_no_resched();
786 kcb->kprobe_status = KPROBE_HIT_SS;
790 preempt_enable_no_resched();
794 static int __kprobes post_kprobes_handler(struct pt_regs *regs)
796 struct kprobe *cur = kprobe_running();
797 struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
802 if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
803 kcb->kprobe_status = KPROBE_HIT_SSDONE;
804 cur->post_handler(cur, regs, 0);
807 resume_execution(cur, regs);
809 /*Restore back the original saved kprobes variables and continue. */
810 if (kcb->kprobe_status == KPROBE_REENTER) {
811 restore_previous_kprobe(kcb);
814 reset_current_kprobe();
817 preempt_enable_no_resched();
821 int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
823 struct kprobe *cur = kprobe_running();
824 struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
827 switch(kcb->kprobe_status) {
831 * We are here because the instruction being single
832 * stepped caused a page fault. We reset the current
833 * kprobe and the instruction pointer points back to
834 * the probe address and allow the page fault handler
835 * to continue as a normal page fault.
837 regs->cr_iip = ((unsigned long)cur->addr) & ~0xFULL;
838 ia64_psr(regs)->ri = ((unsigned long)cur->addr) & 0xf;
839 if (kcb->kprobe_status == KPROBE_REENTER)
840 restore_previous_kprobe(kcb);
842 reset_current_kprobe();
843 preempt_enable_no_resched();
845 case KPROBE_HIT_ACTIVE:
846 case KPROBE_HIT_SSDONE:
848 * In case the user-specified fault handler returned
849 * zero, try to fix up.
851 if (ia64_done_with_exception(regs))
855 * Let ia64_do_page_fault() fix it.
865 int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
866 unsigned long val, void *data)
868 struct die_args *args = (struct die_args *)data;
869 int ret = NOTIFY_DONE;
871 if (args->regs && user_mode(args->regs))
876 /* err is break number from ia64_bad_break() */
877 if ((args->err >> 12) == (__IA64_BREAK_KPROBE >> 12)
879 if (pre_kprobes_handler(args))
883 /* err is vector number from ia64_fault() */
885 if (post_kprobes_handler(args->regs))
894 unsigned long arch_deref_entry_point(void *entry)
896 return ((struct fnptr *)entry)->ip;
899 static struct kprobe trampoline_p = {
900 .pre_handler = trampoline_probe_handler
903 int __init arch_init_kprobes(void)
906 dereference_function_descriptor(kretprobe_trampoline);
907 return register_kprobe(&trampoline_p);
910 int __kprobes arch_trampoline_kprobe(struct kprobe *p)
913 dereference_function_descriptor(kretprobe_trampoline))