|
@@ -0,0 +1,601 @@
|
|
|
|
+/*
|
|
|
|
+ * Kernel Probes (KProbes)
|
|
|
|
+ * arch/ia64/kernel/kprobes.c
|
|
|
|
+ *
|
|
|
|
+ * This program is free software; you can redistribute it and/or modify
|
|
|
|
+ * it under the terms of the GNU General Public License as published by
|
|
|
|
+ * the Free Software Foundation; either version 2 of the License, or
|
|
|
|
+ * (at your option) any later version.
|
|
|
|
+ *
|
|
|
|
+ * This program is distributed in the hope that it will be useful,
|
|
|
|
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
|
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
|
|
+ * GNU General Public License for more details.
|
|
|
|
+ *
|
|
|
|
+ * You should have received a copy of the GNU General Public License
|
|
|
|
+ * along with this program; if not, write to the Free Software
|
|
|
|
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
+ *
|
|
|
|
+ * Copyright (C) IBM Corporation, 2002, 2004
|
|
|
|
+ * Copyright (C) Intel Corporation, 2005
|
|
|
|
+ *
|
|
|
|
+ * 2005-Apr Rusty Lynch <rusty.lynch@intel.com> and Anil S Keshavamurthy
|
|
|
|
+ * <anil.s.keshavamurthy@intel.com> adapted from i386
|
|
|
|
+ */
|
|
|
|
+
|
|
|
|
+#include <linux/config.h>
|
|
|
|
+#include <linux/kprobes.h>
|
|
|
|
+#include <linux/ptrace.h>
|
|
|
|
+#include <linux/spinlock.h>
|
|
|
|
+#include <linux/string.h>
|
|
|
|
+#include <linux/slab.h>
|
|
|
|
+#include <linux/preempt.h>
|
|
|
|
+#include <linux/moduleloader.h>
|
|
|
|
+
|
|
|
|
+#include <asm/pgtable.h>
|
|
|
|
+#include <asm/kdebug.h>
|
|
|
|
+
|
|
|
|
+extern void jprobe_inst_return(void);
|
|
|
|
+
|
|
|
|
+/* kprobe_status settings */
|
|
|
|
+#define KPROBE_HIT_ACTIVE 0x00000001
|
|
|
|
+#define KPROBE_HIT_SS 0x00000002
|
|
|
|
+
|
|
|
|
+static struct kprobe *current_kprobe, *kprobe_prev;
|
|
|
|
+static unsigned long kprobe_status, kprobe_status_prev;
|
|
|
|
+static struct pt_regs jprobe_saved_regs;
|
|
|
|
+
|
|
|
|
+enum instruction_type {A, I, M, F, B, L, X, u};
|
|
|
|
+static enum instruction_type bundle_encoding[32][3] = {
|
|
|
|
+ { M, I, I }, /* 00 */
|
|
|
|
+ { M, I, I }, /* 01 */
|
|
|
|
+ { M, I, I }, /* 02 */
|
|
|
|
+ { M, I, I }, /* 03 */
|
|
|
|
+ { M, L, X }, /* 04 */
|
|
|
|
+ { M, L, X }, /* 05 */
|
|
|
|
+ { u, u, u }, /* 06 */
|
|
|
|
+ { u, u, u }, /* 07 */
|
|
|
|
+ { M, M, I }, /* 08 */
|
|
|
|
+ { M, M, I }, /* 09 */
|
|
|
|
+ { M, M, I }, /* 0A */
|
|
|
|
+ { M, M, I }, /* 0B */
|
|
|
|
+ { M, F, I }, /* 0C */
|
|
|
|
+ { M, F, I }, /* 0D */
|
|
|
|
+ { M, M, F }, /* 0E */
|
|
|
|
+ { M, M, F }, /* 0F */
|
|
|
|
+ { M, I, B }, /* 10 */
|
|
|
|
+ { M, I, B }, /* 11 */
|
|
|
|
+ { M, B, B }, /* 12 */
|
|
|
|
+ { M, B, B }, /* 13 */
|
|
|
|
+ { u, u, u }, /* 14 */
|
|
|
|
+ { u, u, u }, /* 15 */
|
|
|
|
+ { B, B, B }, /* 16 */
|
|
|
|
+ { B, B, B }, /* 17 */
|
|
|
|
+ { M, M, B }, /* 18 */
|
|
|
|
+ { M, M, B }, /* 19 */
|
|
|
|
+ { u, u, u }, /* 1A */
|
|
|
|
+ { u, u, u }, /* 1B */
|
|
|
|
+ { M, F, B }, /* 1C */
|
|
|
|
+ { M, F, B }, /* 1D */
|
|
|
|
+ { u, u, u }, /* 1E */
|
|
|
|
+ { u, u, u }, /* 1F */
|
|
|
|
+};
|
|
|
|
+
|
|
|
|
+/*
|
|
|
|
+ * In this function we check to see if the instruction
|
|
|
|
+ * is IP relative instruction and update the kprobe
|
|
|
|
+ * inst flag accordingly
|
|
|
|
+ */
|
|
|
|
+static void update_kprobe_inst_flag(uint template, uint slot, uint major_opcode,
|
|
|
|
+ unsigned long kprobe_inst, struct kprobe *p)
|
|
|
|
+{
|
|
|
|
+ p->ainsn.inst_flag = 0;
|
|
|
|
+ p->ainsn.target_br_reg = 0;
|
|
|
|
+
|
|
|
|
+ if (bundle_encoding[template][slot] == B) {
|
|
|
|
+ switch (major_opcode) {
|
|
|
|
+ case INDIRECT_CALL_OPCODE:
|
|
|
|
+ p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
|
|
|
|
+ p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
|
|
|
|
+ break;
|
|
|
|
+ case IP_RELATIVE_PREDICT_OPCODE:
|
|
|
|
+ case IP_RELATIVE_BRANCH_OPCODE:
|
|
|
|
+ p->ainsn.inst_flag |= INST_FLAG_FIX_RELATIVE_IP_ADDR;
|
|
|
|
+ break;
|
|
|
|
+ case IP_RELATIVE_CALL_OPCODE:
|
|
|
|
+ p->ainsn.inst_flag |= INST_FLAG_FIX_RELATIVE_IP_ADDR;
|
|
|
|
+ p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
|
|
|
|
+ p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+ } else if (bundle_encoding[template][slot] == X) {
|
|
|
|
+ switch (major_opcode) {
|
|
|
|
+ case LONG_CALL_OPCODE:
|
|
|
|
+ p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
|
|
|
|
+ p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ return;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+/*
|
|
|
|
+ * In this function we check to see if the instruction
|
|
|
|
+ * on which we are inserting kprobe is supported.
|
|
|
|
+ * Returns 0 if supported
|
|
|
|
+ * Returns -EINVAL if unsupported
|
|
|
|
+ */
|
|
|
|
+static int unsupported_inst(uint template, uint slot, uint major_opcode,
|
|
|
|
+ unsigned long kprobe_inst, struct kprobe *p)
|
|
|
|
+{
|
|
|
|
+ unsigned long addr = (unsigned long)p->addr;
|
|
|
|
+
|
|
|
|
+ if (bundle_encoding[template][slot] == I) {
|
|
|
|
+ switch (major_opcode) {
|
|
|
|
+ case 0x0: //I_UNIT_MISC_OPCODE:
|
|
|
|
+ /*
|
|
|
|
+ * Check for Integer speculation instruction
|
|
|
|
+ * - Bit 33-35 to be equal to 0x1
|
|
|
|
+ */
|
|
|
|
+ if (((kprobe_inst >> 33) & 0x7) == 1) {
|
|
|
|
+ printk(KERN_WARNING
|
|
|
|
+ "Kprobes on speculation inst at <0x%lx> not supported\n",
|
|
|
|
+ addr);
|
|
|
|
+ return -EINVAL;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * IP relative mov instruction
|
|
|
|
+ * - Bit 27-35 to be equal to 0x30
|
|
|
|
+ */
|
|
|
|
+ if (((kprobe_inst >> 27) & 0x1FF) == 0x30) {
|
|
|
|
+ printk(KERN_WARNING
|
|
|
|
+ "Kprobes on \"mov r1=ip\" at <0x%lx> not supported\n",
|
|
|
|
+ addr);
|
|
|
|
+ return -EINVAL;
|
|
|
|
+
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ return 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+
|
|
|
|
+/*
|
|
|
|
+ * In this function we check to see if the instruction
|
|
|
|
+ * (qp) cmpx.crel.ctype p1,p2=r2,r3
|
|
|
|
+ * on which we are inserting kprobe is cmp instruction
|
|
|
|
+ * with ctype as unc.
|
|
|
|
+ */
|
|
|
|
+static uint is_cmp_ctype_unc_inst(uint template, uint slot, uint major_opcode,
|
|
|
|
+unsigned long kprobe_inst)
|
|
|
|
+{
|
|
|
|
+ cmp_inst_t cmp_inst;
|
|
|
|
+ uint ctype_unc = 0;
|
|
|
|
+
|
|
|
|
+ if (!((bundle_encoding[template][slot] == I) ||
|
|
|
|
+ (bundle_encoding[template][slot] == M)))
|
|
|
|
+ goto out;
|
|
|
|
+
|
|
|
|
+ if (!((major_opcode == 0xC) || (major_opcode == 0xD) ||
|
|
|
|
+ (major_opcode == 0xE)))
|
|
|
|
+ goto out;
|
|
|
|
+
|
|
|
|
+ cmp_inst.l = kprobe_inst;
|
|
|
|
+ if ((cmp_inst.f.x2 == 0) || (cmp_inst.f.x2 == 1)) {
|
|
|
|
+ /* Integere compare - Register Register (A6 type)*/
|
|
|
|
+ if ((cmp_inst.f.tb == 0) && (cmp_inst.f.ta == 0)
|
|
|
|
+ &&(cmp_inst.f.c == 1))
|
|
|
|
+ ctype_unc = 1;
|
|
|
|
+ } else if ((cmp_inst.f.x2 == 2)||(cmp_inst.f.x2 == 3)) {
|
|
|
|
+ /* Integere compare - Immediate Register (A8 type)*/
|
|
|
|
+ if ((cmp_inst.f.ta == 0) &&(cmp_inst.f.c == 1))
|
|
|
|
+ ctype_unc = 1;
|
|
|
|
+ }
|
|
|
|
+out:
|
|
|
|
+ return ctype_unc;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+/*
|
|
|
|
+ * In this function we override the bundle with
|
|
|
|
+ * the break instruction at the given slot.
|
|
|
|
+ */
|
|
|
|
+static void prepare_break_inst(uint template, uint slot, uint major_opcode,
|
|
|
|
+ unsigned long kprobe_inst, struct kprobe *p)
|
|
|
|
+{
|
|
|
|
+ unsigned long break_inst = BREAK_INST;
|
|
|
|
+ bundle_t *bundle = &p->ainsn.insn.bundle;
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * Copy the original kprobe_inst qualifying predicate(qp)
|
|
|
|
+ * to the break instruction iff !is_cmp_ctype_unc_inst
|
|
|
|
+ * because for cmp instruction with ctype equal to unc,
|
|
|
|
+ * which is a special instruction always needs to be
|
|
|
|
+ * executed regradless of qp
|
|
|
|
+ */
|
|
|
|
+ if (!is_cmp_ctype_unc_inst(template, slot, major_opcode, kprobe_inst))
|
|
|
|
+ break_inst |= (0x3f & kprobe_inst);
|
|
|
|
+
|
|
|
|
+ switch (slot) {
|
|
|
|
+ case 0:
|
|
|
|
+ bundle->quad0.slot0 = break_inst;
|
|
|
|
+ break;
|
|
|
|
+ case 1:
|
|
|
|
+ bundle->quad0.slot1_p0 = break_inst;
|
|
|
|
+ bundle->quad1.slot1_p1 = break_inst >> (64-46);
|
|
|
|
+ break;
|
|
|
|
+ case 2:
|
|
|
|
+ bundle->quad1.slot2 = break_inst;
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * Update the instruction flag, so that we can
|
|
|
|
+ * emulate the instruction properly after we
|
|
|
|
+ * single step on original instruction
|
|
|
|
+ */
|
|
|
|
+ update_kprobe_inst_flag(template, slot, major_opcode, kprobe_inst, p);
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static inline void get_kprobe_inst(bundle_t *bundle, uint slot,
|
|
|
|
+ unsigned long *kprobe_inst, uint *major_opcode)
|
|
|
|
+{
|
|
|
|
+ unsigned long kprobe_inst_p0, kprobe_inst_p1;
|
|
|
|
+ unsigned int template;
|
|
|
|
+
|
|
|
|
+ template = bundle->quad0.template;
|
|
|
|
+
|
|
|
|
+ switch (slot) {
|
|
|
|
+ case 0:
|
|
|
|
+ *major_opcode = (bundle->quad0.slot0 >> SLOT0_OPCODE_SHIFT);
|
|
|
|
+ *kprobe_inst = bundle->quad0.slot0;
|
|
|
|
+ break;
|
|
|
|
+ case 1:
|
|
|
|
+ *major_opcode = (bundle->quad1.slot1_p1 >> SLOT1_p1_OPCODE_SHIFT);
|
|
|
|
+ kprobe_inst_p0 = bundle->quad0.slot1_p0;
|
|
|
|
+ kprobe_inst_p1 = bundle->quad1.slot1_p1;
|
|
|
|
+ *kprobe_inst = kprobe_inst_p0 | (kprobe_inst_p1 << (64-46));
|
|
|
|
+ break;
|
|
|
|
+ case 2:
|
|
|
|
+ *major_opcode = (bundle->quad1.slot2 >> SLOT2_OPCODE_SHIFT);
|
|
|
|
+ *kprobe_inst = bundle->quad1.slot2;
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static int valid_kprobe_addr(int template, int slot, unsigned long addr)
|
|
|
|
+{
|
|
|
|
+ if ((slot > 2) || ((bundle_encoding[template][1] == L) && slot > 1)) {
|
|
|
|
+ printk(KERN_WARNING "Attempting to insert unaligned kprobe at 0x%lx\n",
|
|
|
|
+ addr);
|
|
|
|
+ return -EINVAL;
|
|
|
|
+ }
|
|
|
|
+ return 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static inline void save_previous_kprobe(void)
|
|
|
|
+{
|
|
|
|
+ kprobe_prev = current_kprobe;
|
|
|
|
+ kprobe_status_prev = kprobe_status;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static inline void restore_previous_kprobe(void)
|
|
|
|
+{
|
|
|
|
+ current_kprobe = kprobe_prev;
|
|
|
|
+ kprobe_status = kprobe_status_prev;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static inline void set_current_kprobe(struct kprobe *p)
|
|
|
|
+{
|
|
|
|
+ current_kprobe = p;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+int arch_prepare_kprobe(struct kprobe *p)
|
|
|
|
+{
|
|
|
|
+ unsigned long addr = (unsigned long) p->addr;
|
|
|
|
+ unsigned long *kprobe_addr = (unsigned long *)(addr & ~0xFULL);
|
|
|
|
+ unsigned long kprobe_inst=0;
|
|
|
|
+ unsigned int slot = addr & 0xf, template, major_opcode = 0;
|
|
|
|
+ bundle_t *bundle = &p->ainsn.insn.bundle;
|
|
|
|
+
|
|
|
|
+ memcpy(&p->opcode.bundle, kprobe_addr, sizeof(bundle_t));
|
|
|
|
+ memcpy(&p->ainsn.insn.bundle, kprobe_addr, sizeof(bundle_t));
|
|
|
|
+
|
|
|
|
+ template = bundle->quad0.template;
|
|
|
|
+
|
|
|
|
+ if(valid_kprobe_addr(template, slot, addr))
|
|
|
|
+ return -EINVAL;
|
|
|
|
+
|
|
|
|
+ /* Move to slot 2, if bundle is MLX type and kprobe slot is 1 */
|
|
|
|
+ if (slot == 1 && bundle_encoding[template][1] == L)
|
|
|
|
+ slot++;
|
|
|
|
+
|
|
|
|
+ /* Get kprobe_inst and major_opcode from the bundle */
|
|
|
|
+ get_kprobe_inst(bundle, slot, &kprobe_inst, &major_opcode);
|
|
|
|
+
|
|
|
|
+ if (unsupported_inst(template, slot, major_opcode, kprobe_inst, p))
|
|
|
|
+ return -EINVAL;
|
|
|
|
+
|
|
|
|
+ prepare_break_inst(template, slot, major_opcode, kprobe_inst, p);
|
|
|
|
+
|
|
|
|
+ return 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+void arch_arm_kprobe(struct kprobe *p)
|
|
|
|
+{
|
|
|
|
+ unsigned long addr = (unsigned long)p->addr;
|
|
|
|
+ unsigned long arm_addr = addr & ~0xFULL;
|
|
|
|
+
|
|
|
|
+ memcpy((char *)arm_addr, &p->ainsn.insn.bundle, sizeof(bundle_t));
|
|
|
|
+ flush_icache_range(arm_addr, arm_addr + sizeof(bundle_t));
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+void arch_disarm_kprobe(struct kprobe *p)
|
|
|
|
+{
|
|
|
|
+ unsigned long addr = (unsigned long)p->addr;
|
|
|
|
+ unsigned long arm_addr = addr & ~0xFULL;
|
|
|
|
+
|
|
|
|
+ /* p->opcode contains the original unaltered bundle */
|
|
|
|
+ memcpy((char *) arm_addr, (char *) &p->opcode.bundle, sizeof(bundle_t));
|
|
|
|
+ flush_icache_range(arm_addr, arm_addr + sizeof(bundle_t));
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+void arch_remove_kprobe(struct kprobe *p)
|
|
|
|
+{
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+/*
|
|
|
|
+ * We are resuming execution after a single step fault, so the pt_regs
|
|
|
|
+ * structure reflects the register state after we executed the instruction
|
|
|
|
+ * located in the kprobe (p->ainsn.insn.bundle). We still need to adjust
|
|
|
|
+ * the ip to point back to the original stack address. To set the IP address
|
|
|
|
+ * to original stack address, handle the case where we need to fixup the
|
|
|
|
+ * relative IP address and/or fixup branch register.
|
|
|
|
+ */
|
|
|
|
+static void resume_execution(struct kprobe *p, struct pt_regs *regs)
|
|
|
|
+{
|
|
|
|
+ unsigned long bundle_addr = ((unsigned long) (&p->opcode.bundle)) & ~0xFULL;
|
|
|
|
+ unsigned long resume_addr = (unsigned long)p->addr & ~0xFULL;
|
|
|
|
+ unsigned long template;
|
|
|
|
+ int slot = ((unsigned long)p->addr & 0xf);
|
|
|
|
+
|
|
|
|
+ template = p->opcode.bundle.quad0.template;
|
|
|
|
+
|
|
|
|
+ if (slot == 1 && bundle_encoding[template][1] == L)
|
|
|
|
+ slot = 2;
|
|
|
|
+
|
|
|
|
+ if (p->ainsn.inst_flag) {
|
|
|
|
+
|
|
|
|
+ if (p->ainsn.inst_flag & INST_FLAG_FIX_RELATIVE_IP_ADDR) {
|
|
|
|
+ /* Fix relative IP address */
|
|
|
|
+ regs->cr_iip = (regs->cr_iip - bundle_addr) + resume_addr;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ if (p->ainsn.inst_flag & INST_FLAG_FIX_BRANCH_REG) {
|
|
|
|
+ /*
|
|
|
|
+ * Fix target branch register, software convention is
|
|
|
|
+ * to use either b0 or b6 or b7, so just checking
|
|
|
|
+ * only those registers
|
|
|
|
+ */
|
|
|
|
+ switch (p->ainsn.target_br_reg) {
|
|
|
|
+ case 0:
|
|
|
|
+ if ((regs->b0 == bundle_addr) ||
|
|
|
|
+ (regs->b0 == bundle_addr + 0x10)) {
|
|
|
|
+ regs->b0 = (regs->b0 - bundle_addr) +
|
|
|
|
+ resume_addr;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ case 6:
|
|
|
|
+ if ((regs->b6 == bundle_addr) ||
|
|
|
|
+ (regs->b6 == bundle_addr + 0x10)) {
|
|
|
|
+ regs->b6 = (regs->b6 - bundle_addr) +
|
|
|
|
+ resume_addr;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ case 7:
|
|
|
|
+ if ((regs->b7 == bundle_addr) ||
|
|
|
|
+ (regs->b7 == bundle_addr + 0x10)) {
|
|
|
|
+ regs->b7 = (regs->b7 - bundle_addr) +
|
|
|
|
+ resume_addr;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ } /* end switch */
|
|
|
|
+ }
|
|
|
|
+ goto turn_ss_off;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ if (slot == 2) {
|
|
|
|
+ if (regs->cr_iip == bundle_addr + 0x10) {
|
|
|
|
+ regs->cr_iip = resume_addr + 0x10;
|
|
|
|
+ }
|
|
|
|
+ } else {
|
|
|
|
+ if (regs->cr_iip == bundle_addr) {
|
|
|
|
+ regs->cr_iip = resume_addr;
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+turn_ss_off:
|
|
|
|
+ /* Turn off Single Step bit */
|
|
|
|
+ ia64_psr(regs)->ss = 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static void prepare_ss(struct kprobe *p, struct pt_regs *regs)
|
|
|
|
+{
|
|
|
|
+ unsigned long bundle_addr = (unsigned long) &p->opcode.bundle;
|
|
|
|
+ unsigned long slot = (unsigned long)p->addr & 0xf;
|
|
|
|
+
|
|
|
|
+ /* Update instruction pointer (IIP) and slot number (IPSR.ri) */
|
|
|
|
+ regs->cr_iip = bundle_addr & ~0xFULL;
|
|
|
|
+
|
|
|
|
+ if (slot > 2)
|
|
|
|
+ slot = 0;
|
|
|
|
+
|
|
|
|
+ ia64_psr(regs)->ri = slot;
|
|
|
|
+
|
|
|
|
+ /* turn on single stepping */
|
|
|
|
+ ia64_psr(regs)->ss = 1;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static int pre_kprobes_handler(struct die_args *args)
|
|
|
|
+{
|
|
|
|
+ struct kprobe *p;
|
|
|
|
+ int ret = 0;
|
|
|
|
+ struct pt_regs *regs = args->regs;
|
|
|
|
+ kprobe_opcode_t *addr = (kprobe_opcode_t *)instruction_pointer(regs);
|
|
|
|
+
|
|
|
|
+ preempt_disable();
|
|
|
|
+
|
|
|
|
+ /* Handle recursion cases */
|
|
|
|
+ if (kprobe_running()) {
|
|
|
|
+ p = get_kprobe(addr);
|
|
|
|
+ if (p) {
|
|
|
|
+ if (kprobe_status == KPROBE_HIT_SS) {
|
|
|
|
+ unlock_kprobes();
|
|
|
|
+ goto no_kprobe;
|
|
|
|
+ }
|
|
|
|
+ /* We have reentered the pre_kprobe_handler(), since
|
|
|
|
+ * another probe was hit while within the handler.
|
|
|
|
+ * We here save the original kprobes variables and
|
|
|
|
+ * just single step on the instruction of the new probe
|
|
|
|
+ * without calling any user handlers.
|
|
|
|
+ */
|
|
|
|
+ save_previous_kprobe();
|
|
|
|
+ set_current_kprobe(p);
|
|
|
|
+ p->nmissed++;
|
|
|
|
+ prepare_ss(p, regs);
|
|
|
|
+ kprobe_status = KPROBE_REENTER;
|
|
|
|
+ return 1;
|
|
|
|
+ } else if (args->err == __IA64_BREAK_JPROBE) {
|
|
|
|
+ /*
|
|
|
|
+ * jprobe instrumented function just completed
|
|
|
|
+ */
|
|
|
|
+ p = current_kprobe;
|
|
|
|
+ if (p->break_handler && p->break_handler(p, regs)) {
|
|
|
|
+ goto ss_probe;
|
|
|
|
+ }
|
|
|
|
+ } else {
|
|
|
|
+ /* Not our break */
|
|
|
|
+ goto no_kprobe;
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ lock_kprobes();
|
|
|
|
+ p = get_kprobe(addr);
|
|
|
|
+ if (!p) {
|
|
|
|
+ unlock_kprobes();
|
|
|
|
+ goto no_kprobe;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ kprobe_status = KPROBE_HIT_ACTIVE;
|
|
|
|
+ set_current_kprobe(p);
|
|
|
|
+
|
|
|
|
+ if (p->pre_handler && p->pre_handler(p, regs))
|
|
|
|
+ /*
|
|
|
|
+ * Our pre-handler is specifically requesting that we just
|
|
|
|
+ * do a return. This is handling the case where the
|
|
|
|
+ * pre-handler is really our special jprobe pre-handler.
|
|
|
|
+ */
|
|
|
|
+ return 1;
|
|
|
|
+
|
|
|
|
+ss_probe:
|
|
|
|
+ prepare_ss(p, regs);
|
|
|
|
+ kprobe_status = KPROBE_HIT_SS;
|
|
|
|
+ return 1;
|
|
|
|
+
|
|
|
|
+no_kprobe:
|
|
|
|
+ preempt_enable_no_resched();
|
|
|
|
+ return ret;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static int post_kprobes_handler(struct pt_regs *regs)
|
|
|
|
+{
|
|
|
|
+ if (!kprobe_running())
|
|
|
|
+ return 0;
|
|
|
|
+
|
|
|
|
+ if ((kprobe_status != KPROBE_REENTER) && current_kprobe->post_handler) {
|
|
|
|
+ kprobe_status = KPROBE_HIT_SSDONE;
|
|
|
|
+ current_kprobe->post_handler(current_kprobe, regs, 0);
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ resume_execution(current_kprobe, regs);
|
|
|
|
+
|
|
|
|
+ /*Restore back the original saved kprobes variables and continue. */
|
|
|
|
+ if (kprobe_status == KPROBE_REENTER) {
|
|
|
|
+ restore_previous_kprobe();
|
|
|
|
+ goto out;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ unlock_kprobes();
|
|
|
|
+
|
|
|
|
+out:
|
|
|
|
+ preempt_enable_no_resched();
|
|
|
|
+ return 1;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static int kprobes_fault_handler(struct pt_regs *regs, int trapnr)
|
|
|
|
+{
|
|
|
|
+ if (!kprobe_running())
|
|
|
|
+ return 0;
|
|
|
|
+
|
|
|
|
+ if (current_kprobe->fault_handler &&
|
|
|
|
+ current_kprobe->fault_handler(current_kprobe, regs, trapnr))
|
|
|
|
+ return 1;
|
|
|
|
+
|
|
|
|
+ if (kprobe_status & KPROBE_HIT_SS) {
|
|
|
|
+ resume_execution(current_kprobe, regs);
|
|
|
|
+ unlock_kprobes();
|
|
|
|
+ preempt_enable_no_resched();
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ return 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val,
|
|
|
|
+ void *data)
|
|
|
|
+{
|
|
|
|
+ struct die_args *args = (struct die_args *)data;
|
|
|
|
+ switch(val) {
|
|
|
|
+ case DIE_BREAK:
|
|
|
|
+ if (pre_kprobes_handler(args))
|
|
|
|
+ return NOTIFY_STOP;
|
|
|
|
+ break;
|
|
|
|
+ case DIE_SS:
|
|
|
|
+ if (post_kprobes_handler(args->regs))
|
|
|
|
+ return NOTIFY_STOP;
|
|
|
|
+ break;
|
|
|
|
+ case DIE_PAGE_FAULT:
|
|
|
|
+ if (kprobes_fault_handler(args->regs, args->trapnr))
|
|
|
|
+ return NOTIFY_STOP;
|
|
|
|
+ default:
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+ return NOTIFY_DONE;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
|
|
|
|
+{
|
|
|
|
+ struct jprobe *jp = container_of(p, struct jprobe, kp);
|
|
|
|
+ unsigned long addr = ((struct fnptr *)(jp->entry))->ip;
|
|
|
|
+
|
|
|
|
+ /* save architectural state */
|
|
|
|
+ jprobe_saved_regs = *regs;
|
|
|
|
+
|
|
|
|
+ /* after rfi, execute the jprobe instrumented function */
|
|
|
|
+ regs->cr_iip = addr & ~0xFULL;
|
|
|
|
+ ia64_psr(regs)->ri = addr & 0xf;
|
|
|
|
+ regs->r1 = ((struct fnptr *)(jp->entry))->gp;
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * fix the return address to our jprobe_inst_return() function
|
|
|
|
+ * in the jprobes.S file
|
|
|
|
+ */
|
|
|
|
+ regs->b0 = ((struct fnptr *)(jprobe_inst_return))->ip;
|
|
|
|
+
|
|
|
|
+ return 1;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
|
|
|
|
+{
|
|
|
|
+ *regs = jprobe_saved_regs;
|
|
|
|
+ return 1;
|
|
|
|
+}
|