linux/arch/ia64/kernel/kprobes.c

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/*
* 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/kprobes.h>
#include <linux/ptrace.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/preempt.h>
#include <linux/moduleloader.h>
#include <linux/kdebug.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/uaccess.h>
extern void jprobe_inst_return(void);
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
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 __kprobes 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;
p->ainsn.slot = slot;
/* Check for Break instruction
* Bits 37:40 Major opcode to be zero
* Bits 27:32 X6 to be zero
* Bits 32:35 X3 to be zero
*/
if ((!major_opcode) && (!((kprobe_inst >> 27) & 0x1FF)) ) {
/* is a break instruction */
p->ainsn.inst_flag |= INST_FLAG_BREAK_INST;
return;
}
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
* (qp) cmpx.crel.ctype p1,p2=r2,r3
* on which we are inserting kprobe is cmp instruction
* with ctype as unc.
*/
static uint __kprobes 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 check to see if the instruction
* on which we are inserting kprobe is supported.
* Returns qp value if supported
* Returns -EINVAL if unsupported
*/
static int __kprobes unsupported_inst(uint template, uint slot,
uint major_opcode,
unsigned long kprobe_inst,
unsigned long addr)
{
int qp;
qp = kprobe_inst & 0x3f;
if (is_cmp_ctype_unc_inst(template, slot, major_opcode, kprobe_inst)) {
if (slot == 1 && qp) {
printk(KERN_WARNING "Kprobes on cmp unc"
"instruction on slot 1 at <0x%lx>"
"is not supported\n", addr);
return -EINVAL;
}
qp = 0;
}
else if (bundle_encoding[template][slot] == I) {
if (major_opcode == 0) {
/*
* 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;
}
}
else if ((major_opcode == 5) && !(kprobe_inst & (0xFUl << 33)) &&
(kprobe_inst & (0x1UL << 12))) {
/* test bit instructions, tbit,tnat,tf
* bit 33-36 to be equal to 0
* bit 12 to be equal to 1
*/
if (slot == 1 && qp) {
printk(KERN_WARNING "Kprobes on test bit"
"instruction on slot at <0x%lx>"
"is not supported\n", addr);
return -EINVAL;
}
qp = 0;
}
}
else if (bundle_encoding[template][slot] == B) {
if (major_opcode == 7) {
/* IP-Relative Predict major code is 7 */
printk(KERN_WARNING "Kprobes on IP-Relative"
"Predict is not supported\n");
return -EINVAL;
}
else if (major_opcode == 2) {
/* Indirect Predict, major code is 2
* bit 27-32 to be equal to 10 or 11
*/
int x6=(kprobe_inst >> 27) & 0x3F;
if ((x6 == 0x10) || (x6 == 0x11)) {
printk(KERN_WARNING "Kprobes on"
"Indirect Predict is not supported\n");
return -EINVAL;
}
}
}
/* kernel does not use float instruction, here for safety kprobe
* will judge whether it is fcmp/flass/float approximation instruction
*/
else if (unlikely(bundle_encoding[template][slot] == F)) {
if ((major_opcode == 4 || major_opcode == 5) &&
(kprobe_inst & (0x1 << 12))) {
/* fcmp/fclass unc instruction */
if (slot == 1 && qp) {
printk(KERN_WARNING "Kprobes on fcmp/fclass "
"instruction on slot at <0x%lx> "
"is not supported\n", addr);
return -EINVAL;
}
qp = 0;
}
if ((major_opcode == 0 || major_opcode == 1) &&
(kprobe_inst & (0x1UL << 33))) {
/* float Approximation instruction */
if (slot == 1 && qp) {
printk(KERN_WARNING "Kprobes on float Approx "
"instr at <0x%lx> is not supported\n",
addr);
return -EINVAL;
}
qp = 0;
}
}
return qp;
}
/*
* In this function we override the bundle with
* the break instruction at the given slot.
*/
static void __kprobes prepare_break_inst(uint template, uint slot,
uint major_opcode,
unsigned long kprobe_inst,
struct kprobe *p,
int qp)
{
unsigned long break_inst = BREAK_INST;
bundle_t *bundle = &p->opcode.bundle;
/*
* Copy the original kprobe_inst qualifying predicate(qp)
* to the break instruction
*/
break_inst |= qp;
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 void __kprobes 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;
}
}
/* Returns non-zero if the addr is in the Interrupt Vector Table */
static int __kprobes in_ivt_functions(unsigned long addr)
{
return (addr >= (unsigned long)__start_ivt_text
&& addr < (unsigned long)__end_ivt_text);
}
static int __kprobes 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;
}
if (in_ivt_functions(addr)) {
printk(KERN_WARNING "Kprobes can't be inserted inside "
"IVT functions at 0x%lx\n", addr);
return -EINVAL;
}
return 0;
}
static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb)
{
kcb->prev_kprobe.kp = kprobe_running();
kcb->prev_kprobe.status = kcb->kprobe_status;
}
static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
{
__get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp;
kcb->kprobe_status = kcb->prev_kprobe.status;
}
static void __kprobes set_current_kprobe(struct kprobe *p,
struct kprobe_ctlblk *kcb)
{
__get_cpu_var(current_kprobe) = p;
}
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
static void kretprobe_trampoline(void)
{
}
/*
* At this point the target function has been tricked into
* returning into our trampoline. Lookup the associated instance
* and then:
* - call the handler function
* - cleanup by marking the instance as unused
* - long jump back to the original return address
*/
int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
{
struct kretprobe_instance *ri = NULL;
struct hlist_head *head, empty_rp;
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
struct hlist_node *node, *tmp;
unsigned long flags, orig_ret_address = 0;
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
unsigned long trampoline_address =
((struct fnptr *)kretprobe_trampoline)->ip;
INIT_HLIST_HEAD(&empty_rp);
spin_lock_irqsave(&kretprobe_lock, flags);
[IA64] Extend notify_die() hooks for IA64 notify_die() added for MCA_{MONARCH,SLAVE,RENDEZVOUS}_{ENTER,PROCESS,LEAVE} and INIT_{MONARCH,SLAVE}_{ENTER,PROCESS,LEAVE}. We need multiple notification points for these events because they can take many seconds to run which has nasty effects on the behaviour of the rest of the system. DIE_SS replaced by a generic DIE_FAULT which checks the vector number, to allow interception of faults other than SS. DIE_MACHINE_{HALT,RESTART} added to allow last minute close down processing, especially when the halt/restart routines are called from error handlers. DIE_OOPS added. The check for kprobe's break numbers has been moved from traps.c to kprobes.c, allowing DIE_BREAK to be used for any additional break numbers, i.e. it is no longer kprobes specific. Hooks for kernel debuggers and kernel dumpers added, ENTER and LEAVE. Both of these disable the system for long periods which impact on watchdogs and heartbeat systems in general. More patches to come that use these events to reset watchdogs and heartbeats. unregister_die_notifier() added and both routines exported. Requested by Dean Nelson. Lock removed from {un,}register_die_notifier. notifier_chain_register() already takes a lock. Also the generic notifier chain locking is being reworked to distinguish between callbacks that can block and those that cannot, the lock in {un,}register_die_notifier would interfere with that change. http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 Leading white space removed from arch/ia64/kernel/kprobes.c. Typo in mca.c in original version of this patch found & fixed by Dean Nelson. Signed-off-by: Keith Owens <kaos@sgi.com> Acked-by: Dean Nelson <dcn@sgi.com> Acked-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-11-08 03:27:13 +08:00
head = kretprobe_inst_table_head(current);
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
/*
* It is possible to have multiple instances associated with a given
* task either because an multiple functions in the call path
* have a return probe installed on them, and/or more then one return
* return probe was registered for a target function.
*
* We can handle this because:
* - instances are always inserted at the head of the list
* - when multiple return probes are registered for the same
* function, the first instance's ret_addr will point to the
* real return address, and all the rest will point to
* kretprobe_trampoline
*/
hlist_for_each_entry_safe(ri, node, tmp, head, hlist) {
[IA64] Extend notify_die() hooks for IA64 notify_die() added for MCA_{MONARCH,SLAVE,RENDEZVOUS}_{ENTER,PROCESS,LEAVE} and INIT_{MONARCH,SLAVE}_{ENTER,PROCESS,LEAVE}. We need multiple notification points for these events because they can take many seconds to run which has nasty effects on the behaviour of the rest of the system. DIE_SS replaced by a generic DIE_FAULT which checks the vector number, to allow interception of faults other than SS. DIE_MACHINE_{HALT,RESTART} added to allow last minute close down processing, especially when the halt/restart routines are called from error handlers. DIE_OOPS added. The check for kprobe's break numbers has been moved from traps.c to kprobes.c, allowing DIE_BREAK to be used for any additional break numbers, i.e. it is no longer kprobes specific. Hooks for kernel debuggers and kernel dumpers added, ENTER and LEAVE. Both of these disable the system for long periods which impact on watchdogs and heartbeat systems in general. More patches to come that use these events to reset watchdogs and heartbeats. unregister_die_notifier() added and both routines exported. Requested by Dean Nelson. Lock removed from {un,}register_die_notifier. notifier_chain_register() already takes a lock. Also the generic notifier chain locking is being reworked to distinguish between callbacks that can block and those that cannot, the lock in {un,}register_die_notifier would interfere with that change. http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 Leading white space removed from arch/ia64/kernel/kprobes.c. Typo in mca.c in original version of this patch found & fixed by Dean Nelson. Signed-off-by: Keith Owens <kaos@sgi.com> Acked-by: Dean Nelson <dcn@sgi.com> Acked-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-11-08 03:27:13 +08:00
if (ri->task != current)
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
/* another task is sharing our hash bucket */
[IA64] Extend notify_die() hooks for IA64 notify_die() added for MCA_{MONARCH,SLAVE,RENDEZVOUS}_{ENTER,PROCESS,LEAVE} and INIT_{MONARCH,SLAVE}_{ENTER,PROCESS,LEAVE}. We need multiple notification points for these events because they can take many seconds to run which has nasty effects on the behaviour of the rest of the system. DIE_SS replaced by a generic DIE_FAULT which checks the vector number, to allow interception of faults other than SS. DIE_MACHINE_{HALT,RESTART} added to allow last minute close down processing, especially when the halt/restart routines are called from error handlers. DIE_OOPS added. The check for kprobe's break numbers has been moved from traps.c to kprobes.c, allowing DIE_BREAK to be used for any additional break numbers, i.e. it is no longer kprobes specific. Hooks for kernel debuggers and kernel dumpers added, ENTER and LEAVE. Both of these disable the system for long periods which impact on watchdogs and heartbeat systems in general. More patches to come that use these events to reset watchdogs and heartbeats. unregister_die_notifier() added and both routines exported. Requested by Dean Nelson. Lock removed from {un,}register_die_notifier. notifier_chain_register() already takes a lock. Also the generic notifier chain locking is being reworked to distinguish between callbacks that can block and those that cannot, the lock in {un,}register_die_notifier would interfere with that change. http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 Leading white space removed from arch/ia64/kernel/kprobes.c. Typo in mca.c in original version of this patch found & fixed by Dean Nelson. Signed-off-by: Keith Owens <kaos@sgi.com> Acked-by: Dean Nelson <dcn@sgi.com> Acked-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-11-08 03:27:13 +08:00
continue;
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
if (ri->rp && ri->rp->handler)
ri->rp->handler(ri, regs);
orig_ret_address = (unsigned long)ri->ret_addr;
recycle_rp_inst(ri, &empty_rp);
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
if (orig_ret_address != trampoline_address)
/*
* This is the real return address. Any other
* instances associated with this task are for
* other calls deeper on the call stack
*/
break;
}
kretprobe_assert(ri, orig_ret_address, trampoline_address);
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
regs->cr_iip = orig_ret_address;
reset_current_kprobe();
spin_unlock_irqrestore(&kretprobe_lock, flags);
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
preempt_enable_no_resched();
hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
hlist_del(&ri->hlist);
kfree(ri);
}
/*
* By returning a non-zero value, we are telling
* kprobe_handler() that we don't want the post_handler
* to run (and have re-enabled preemption)
*/
[IA64] Extend notify_die() hooks for IA64 notify_die() added for MCA_{MONARCH,SLAVE,RENDEZVOUS}_{ENTER,PROCESS,LEAVE} and INIT_{MONARCH,SLAVE}_{ENTER,PROCESS,LEAVE}. We need multiple notification points for these events because they can take many seconds to run which has nasty effects on the behaviour of the rest of the system. DIE_SS replaced by a generic DIE_FAULT which checks the vector number, to allow interception of faults other than SS. DIE_MACHINE_{HALT,RESTART} added to allow last minute close down processing, especially when the halt/restart routines are called from error handlers. DIE_OOPS added. The check for kprobe's break numbers has been moved from traps.c to kprobes.c, allowing DIE_BREAK to be used for any additional break numbers, i.e. it is no longer kprobes specific. Hooks for kernel debuggers and kernel dumpers added, ENTER and LEAVE. Both of these disable the system for long periods which impact on watchdogs and heartbeat systems in general. More patches to come that use these events to reset watchdogs and heartbeats. unregister_die_notifier() added and both routines exported. Requested by Dean Nelson. Lock removed from {un,}register_die_notifier. notifier_chain_register() already takes a lock. Also the generic notifier chain locking is being reworked to distinguish between callbacks that can block and those that cannot, the lock in {un,}register_die_notifier would interfere with that change. http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 Leading white space removed from arch/ia64/kernel/kprobes.c. Typo in mca.c in original version of this patch found & fixed by Dean Nelson. Signed-off-by: Keith Owens <kaos@sgi.com> Acked-by: Dean Nelson <dcn@sgi.com> Acked-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-11-08 03:27:13 +08:00
return 1;
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
}
/* Called with kretprobe_lock held */
void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
struct pt_regs *regs)
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
{
ri->ret_addr = (kprobe_opcode_t *)regs->b0;
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
/* Replace the return addr with trampoline addr */
regs->b0 = ((struct fnptr *)kretprobe_trampoline)->ip;
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
}
int __kprobes 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;
int qp;
bundle = &((kprobe_opcode_t *)kprobe_addr)->bundle;
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);
qp = unsupported_inst(template, slot, major_opcode, kprobe_inst, addr);
if (qp < 0)
return -EINVAL;
p->ainsn.insn = get_insn_slot();
if (!p->ainsn.insn)
return -ENOMEM;
memcpy(&p->opcode, kprobe_addr, sizeof(kprobe_opcode_t));
memcpy(p->ainsn.insn, kprobe_addr, sizeof(kprobe_opcode_t));
prepare_break_inst(template, slot, major_opcode, kprobe_inst, p, qp);
return 0;
}
void __kprobes arch_arm_kprobe(struct kprobe *p)
{
unsigned long arm_addr;
bundle_t *src, *dest;
arm_addr = ((unsigned long)p->addr) & ~0xFUL;
dest = &((kprobe_opcode_t *)arm_addr)->bundle;
src = &p->opcode.bundle;
flush_icache_range((unsigned long)p->ainsn.insn,
(unsigned long)p->ainsn.insn + sizeof(kprobe_opcode_t));
switch (p->ainsn.slot) {
case 0:
dest->quad0.slot0 = src->quad0.slot0;
break;
case 1:
dest->quad1.slot1_p1 = src->quad1.slot1_p1;
break;
case 2:
dest->quad1.slot2 = src->quad1.slot2;
break;
}
flush_icache_range(arm_addr, arm_addr + sizeof(kprobe_opcode_t));
}
void __kprobes arch_disarm_kprobe(struct kprobe *p)
{
unsigned long arm_addr;
bundle_t *src, *dest;
arm_addr = ((unsigned long)p->addr) & ~0xFUL;
dest = &((kprobe_opcode_t *)arm_addr)->bundle;
/* p->ainsn.insn contains the original unaltered kprobe_opcode_t */
src = &p->ainsn.insn->bundle;
switch (p->ainsn.slot) {
case 0:
dest->quad0.slot0 = src->quad0.slot0;
break;
case 1:
dest->quad1.slot1_p1 = src->quad1.slot1_p1;
break;
case 2:
dest->quad1.slot2 = src->quad1.slot2;
break;
}
flush_icache_range(arm_addr, arm_addr + sizeof(kprobe_opcode_t));
}
void __kprobes arch_remove_kprobe(struct kprobe *p)
{
mutex_lock(&kprobe_mutex);
[PATCH] kprobes: enable booster on the preemptible kernel When we are unregistering a kprobe-booster, we can't release its instruction buffer immediately on the preemptive kernel, because some processes might be preempted on the buffer. The freeze_processes() and thaw_processes() functions can clean most of processes up from the buffer. There are still some non-frozen threads who have the PF_NOFREEZE flag. If those threads are sleeping (not preempted) at the known place outside the buffer, we can ensure safety of freeing. However, the processing of this check routine takes a long time. So, this patch introduces the garbage collection mechanism of insn_slot. It also introduces the "dirty" flag to free_insn_slot because of efficiency. The "clean" instruction slots (dirty flag is cleared) are released immediately. But the "dirty" slots which are used by boosted kprobes, are marked as garbages. collect_garbage_slots() will be invoked to release "dirty" slots if there are more than INSNS_PER_PAGE garbage slots or if there are no unused slots. Cc: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: "bibo,mao" <bibo.mao@intel.com> Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com> Cc: Yumiko Sugita <yumiko.sugita.yf@hitachi.com> Cc: Satoshi Oshima <soshima@redhat.com> Cc: Hideo Aoki <haoki@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 12:38:11 +08:00
free_insn_slot(p->ainsn.insn, 0);
mutex_unlock(&kprobe_mutex);
}
/*
* 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 __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs)
{
unsigned long bundle_addr = (unsigned long) (&p->ainsn.insn->bundle);
unsigned long resume_addr = (unsigned long)p->addr & ~0xFULL;
unsigned long template;
int slot = ((unsigned long)p->addr & 0xf);
template = p->ainsn.insn->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 __kprobes prepare_ss(struct kprobe *p, struct pt_regs *regs)
{
unsigned long bundle_addr = (unsigned long) &p->ainsn.insn->bundle;
unsigned long slot = (unsigned long)p->addr & 0xf;
/* single step inline if break instruction */
if (p->ainsn.inst_flag == INST_FLAG_BREAK_INST)
regs->cr_iip = (unsigned long)p->addr & ~0xFULL;
else
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 __kprobes is_ia64_break_inst(struct pt_regs *regs)
{
unsigned int slot = ia64_psr(regs)->ri;
unsigned int template, major_opcode;
unsigned long kprobe_inst;
unsigned long *kprobe_addr = (unsigned long *)regs->cr_iip;
bundle_t bundle;
memcpy(&bundle, kprobe_addr, sizeof(bundle_t));
template = bundle.quad0.template;
/* 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 probe instruction at given slot*/
get_kprobe_inst(&bundle, slot, &kprobe_inst, &major_opcode);
/* For break instruction,
* Bits 37:40 Major opcode to be zero
* Bits 27:32 X6 to be zero
* Bits 32:35 X3 to be zero
*/
if (major_opcode || ((kprobe_inst >> 27) & 0x1FF) ) {
/* Not a break instruction */
return 0;
}
/* Is a break instruction */
return 1;
}
static int __kprobes 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);
struct kprobe_ctlblk *kcb;
/*
* We don't want to be preempted for the entire
* duration of kprobe processing
*/
preempt_disable();
kcb = get_kprobe_ctlblk();
/* Handle recursion cases */
if (kprobe_running()) {
p = get_kprobe(addr);
if (p) {
if ((kcb->kprobe_status == KPROBE_HIT_SS) &&
(p->ainsn.inst_flag == INST_FLAG_BREAK_INST)) {
ia64_psr(regs)->ss = 0;
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(kcb);
set_current_kprobe(p, kcb);
kprobes_inc_nmissed_count(p);
prepare_ss(p, regs);
kcb->kprobe_status = KPROBE_REENTER;
return 1;
} else if (args->err == __IA64_BREAK_JPROBE) {
/*
* jprobe instrumented function just completed
*/
p = __get_cpu_var(current_kprobe);
if (p->break_handler && p->break_handler(p, regs)) {
goto ss_probe;
}
} else if (!is_ia64_break_inst(regs)) {
/* The breakpoint instruction was removed by
* another cpu right after we hit, no further
* handling of this interrupt is appropriate
*/
ret = 1;
goto no_kprobe;
} else {
/* Not our break */
goto no_kprobe;
}
}
p = get_kprobe(addr);
if (!p) {
if (!is_ia64_break_inst(regs)) {
/*
* The breakpoint instruction was removed right
* after we hit it. Another cpu has removed
* either a probepoint or a debugger breakpoint
* at this address. In either case, no further
* handling of this interrupt is appropriate.
*/
ret = 1;
}
/* Not one of our break, let kernel handle it */
goto no_kprobe;
}
set_current_kprobe(p, kcb);
kcb->kprobe_status = KPROBE_HIT_ACTIVE;
if (p->pre_handler && p->pre_handler(p, regs))
/*
* Our pre-handler is specifically requesting that we just
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
* do a return. This is used for both the jprobe pre-handler
* and the kretprobe trampoline
*/
return 1;
ss_probe:
prepare_ss(p, regs);
kcb->kprobe_status = KPROBE_HIT_SS;
return 1;
no_kprobe:
preempt_enable_no_resched();
return ret;
}
static int __kprobes post_kprobes_handler(struct pt_regs *regs)
{
struct kprobe *cur = kprobe_running();
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
if (!cur)
return 0;
if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
kcb->kprobe_status = KPROBE_HIT_SSDONE;
cur->post_handler(cur, regs, 0);
}
resume_execution(cur, regs);
/*Restore back the original saved kprobes variables and continue. */
if (kcb->kprobe_status == KPROBE_REENTER) {
restore_previous_kprobe(kcb);
goto out;
}
reset_current_kprobe();
out:
preempt_enable_no_resched();
return 1;
}
static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr)
{
struct kprobe *cur = kprobe_running();
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
switch(kcb->kprobe_status) {
case KPROBE_HIT_SS:
case KPROBE_REENTER:
/*
* We are here because the instruction being single
* stepped caused a page fault. We reset the current
* kprobe and the instruction pointer points back to
* the probe address and allow the page fault handler
* to continue as a normal page fault.
*/
regs->cr_iip = ((unsigned long)cur->addr) & ~0xFULL;
ia64_psr(regs)->ri = ((unsigned long)cur->addr) & 0xf;
if (kcb->kprobe_status == KPROBE_REENTER)
restore_previous_kprobe(kcb);
else
reset_current_kprobe();
preempt_enable_no_resched();
break;
case KPROBE_HIT_ACTIVE:
case KPROBE_HIT_SSDONE:
/*
* We increment the nmissed count for accounting,
* we can also use npre/npostfault count for accouting
* these specific fault cases.
*/
kprobes_inc_nmissed_count(cur);
/*
* We come here because instructions in the pre/post
* handler caused the page_fault, this could happen
* if handler tries to access user space by
* copy_from_user(), get_user() etc. Let the
* user-specified handler try to fix it first.
*/
if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
return 1;
/*
* In case the user-specified fault handler returned
* zero, try to fix up.
*/
if (ia64_done_with_exception(regs))
return 1;
/*
* Let ia64_do_page_fault() fix it.
*/
break;
default:
break;
}
return 0;
}
int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data)
{
struct die_args *args = (struct die_args *)data;
2005-11-07 17:00:07 +08:00
int ret = NOTIFY_DONE;
if (args->regs && user_mode(args->regs))
return ret;
switch(val) {
case DIE_BREAK:
[IA64] Extend notify_die() hooks for IA64 notify_die() added for MCA_{MONARCH,SLAVE,RENDEZVOUS}_{ENTER,PROCESS,LEAVE} and INIT_{MONARCH,SLAVE}_{ENTER,PROCESS,LEAVE}. We need multiple notification points for these events because they can take many seconds to run which has nasty effects on the behaviour of the rest of the system. DIE_SS replaced by a generic DIE_FAULT which checks the vector number, to allow interception of faults other than SS. DIE_MACHINE_{HALT,RESTART} added to allow last minute close down processing, especially when the halt/restart routines are called from error handlers. DIE_OOPS added. The check for kprobe's break numbers has been moved from traps.c to kprobes.c, allowing DIE_BREAK to be used for any additional break numbers, i.e. it is no longer kprobes specific. Hooks for kernel debuggers and kernel dumpers added, ENTER and LEAVE. Both of these disable the system for long periods which impact on watchdogs and heartbeat systems in general. More patches to come that use these events to reset watchdogs and heartbeats. unregister_die_notifier() added and both routines exported. Requested by Dean Nelson. Lock removed from {un,}register_die_notifier. notifier_chain_register() already takes a lock. Also the generic notifier chain locking is being reworked to distinguish between callbacks that can block and those that cannot, the lock in {un,}register_die_notifier would interfere with that change. http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 Leading white space removed from arch/ia64/kernel/kprobes.c. Typo in mca.c in original version of this patch found & fixed by Dean Nelson. Signed-off-by: Keith Owens <kaos@sgi.com> Acked-by: Dean Nelson <dcn@sgi.com> Acked-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-11-08 03:27:13 +08:00
/* err is break number from ia64_bad_break() */
if ((args->err >> 12) == (__IA64_BREAK_KPROBE >> 12)
|| args->err == __IA64_BREAK_JPROBE
|| args->err == 0)
[IA64] Extend notify_die() hooks for IA64 notify_die() added for MCA_{MONARCH,SLAVE,RENDEZVOUS}_{ENTER,PROCESS,LEAVE} and INIT_{MONARCH,SLAVE}_{ENTER,PROCESS,LEAVE}. We need multiple notification points for these events because they can take many seconds to run which has nasty effects on the behaviour of the rest of the system. DIE_SS replaced by a generic DIE_FAULT which checks the vector number, to allow interception of faults other than SS. DIE_MACHINE_{HALT,RESTART} added to allow last minute close down processing, especially when the halt/restart routines are called from error handlers. DIE_OOPS added. The check for kprobe's break numbers has been moved from traps.c to kprobes.c, allowing DIE_BREAK to be used for any additional break numbers, i.e. it is no longer kprobes specific. Hooks for kernel debuggers and kernel dumpers added, ENTER and LEAVE. Both of these disable the system for long periods which impact on watchdogs and heartbeat systems in general. More patches to come that use these events to reset watchdogs and heartbeats. unregister_die_notifier() added and both routines exported. Requested by Dean Nelson. Lock removed from {un,}register_die_notifier. notifier_chain_register() already takes a lock. Also the generic notifier chain locking is being reworked to distinguish between callbacks that can block and those that cannot, the lock in {un,}register_die_notifier would interfere with that change. http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 Leading white space removed from arch/ia64/kernel/kprobes.c. Typo in mca.c in original version of this patch found & fixed by Dean Nelson. Signed-off-by: Keith Owens <kaos@sgi.com> Acked-by: Dean Nelson <dcn@sgi.com> Acked-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-11-08 03:27:13 +08:00
if (pre_kprobes_handler(args))
ret = NOTIFY_STOP;
break;
[IA64] Extend notify_die() hooks for IA64 notify_die() added for MCA_{MONARCH,SLAVE,RENDEZVOUS}_{ENTER,PROCESS,LEAVE} and INIT_{MONARCH,SLAVE}_{ENTER,PROCESS,LEAVE}. We need multiple notification points for these events because they can take many seconds to run which has nasty effects on the behaviour of the rest of the system. DIE_SS replaced by a generic DIE_FAULT which checks the vector number, to allow interception of faults other than SS. DIE_MACHINE_{HALT,RESTART} added to allow last minute close down processing, especially when the halt/restart routines are called from error handlers. DIE_OOPS added. The check for kprobe's break numbers has been moved from traps.c to kprobes.c, allowing DIE_BREAK to be used for any additional break numbers, i.e. it is no longer kprobes specific. Hooks for kernel debuggers and kernel dumpers added, ENTER and LEAVE. Both of these disable the system for long periods which impact on watchdogs and heartbeat systems in general. More patches to come that use these events to reset watchdogs and heartbeats. unregister_die_notifier() added and both routines exported. Requested by Dean Nelson. Lock removed from {un,}register_die_notifier. notifier_chain_register() already takes a lock. Also the generic notifier chain locking is being reworked to distinguish between callbacks that can block and those that cannot, the lock in {un,}register_die_notifier would interfere with that change. http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 Leading white space removed from arch/ia64/kernel/kprobes.c. Typo in mca.c in original version of this patch found & fixed by Dean Nelson. Signed-off-by: Keith Owens <kaos@sgi.com> Acked-by: Dean Nelson <dcn@sgi.com> Acked-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-11-08 03:27:13 +08:00
case DIE_FAULT:
/* err is vector number from ia64_fault() */
if (args->err == 36)
if (post_kprobes_handler(args->regs))
ret = NOTIFY_STOP;
break;
case DIE_PAGE_FAULT:
/* kprobe_running() needs smp_processor_id() */
preempt_disable();
if (kprobe_running() &&
kprobes_fault_handler(args->regs, args->trapnr))
2005-11-07 17:00:07 +08:00
ret = NOTIFY_STOP;
preempt_enable();
default:
break;
}
2005-11-07 17:00:07 +08:00
return ret;
}
struct param_bsp_cfm {
unsigned long ip;
unsigned long *bsp;
unsigned long cfm;
};
static void ia64_get_bsp_cfm(struct unw_frame_info *info, void *arg)
{
unsigned long ip;
struct param_bsp_cfm *lp = arg;
do {
unw_get_ip(info, &ip);
if (ip == 0)
break;
if (ip == lp->ip) {
unw_get_bsp(info, (unsigned long*)&lp->bsp);
unw_get_cfm(info, (unsigned long*)&lp->cfm);
return;
}
} while (unw_unwind(info) >= 0);
lp->bsp = NULL;
lp->cfm = 0;
return;
}
int __kprobes 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;
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
struct param_bsp_cfm pa;
int bytes;
/*
* Callee owns the argument space and could overwrite it, eg
* tail call optimization. So to be absolutely safe
* we save the argument space before transfering the control
* to instrumented jprobe function which runs in
* the process context
*/
pa.ip = regs->cr_iip;
unw_init_running(ia64_get_bsp_cfm, &pa);
bytes = (char *)ia64_rse_skip_regs(pa.bsp, pa.cfm & 0x3f)
- (char *)pa.bsp;
memcpy( kcb->jprobes_saved_stacked_regs,
pa.bsp,
bytes );
kcb->bsp = pa.bsp;
kcb->cfm = pa.cfm;
/* save architectural state */
kcb->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 __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
{
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
int bytes;
/* restoring architectural state */
*regs = kcb->jprobe_saved_regs;
/* restoring the original argument space */
flush_register_stack();
bytes = (char *)ia64_rse_skip_regs(kcb->bsp, kcb->cfm & 0x3f)
- (char *)kcb->bsp;
memcpy( kcb->bsp,
kcb->jprobes_saved_stacked_regs,
bytes );
invalidate_stacked_regs();
preempt_enable_no_resched();
return 1;
}
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
static struct kprobe trampoline_p = {
.pre_handler = trampoline_probe_handler
};
int __init arch_init_kprobes(void)
[PATCH] Return probe redesign: ia64 specific implementation The following patch implements function return probes for ia64 using the revised design. With this new design we no longer need to do some of the odd hacks previous required on the last ia64 return probe port that I sent out for comments. Note that this new implementation still does not resolve the problem noted by Keith Owens where backtrace data is lost after a return probe is hit. Changes include: * Addition of kretprobe_trampoline to act as a dummy function for instrumented functions to return to, and for the return probe infrastructure to place a kprobe on on, gaining control so that the return probe handler can be called, and so that the instruction pointer can be moved back to the original return address. * Addition of arch_init(), allowing a kprobe to be registered on kretprobe_trampoline * Addition of trampoline_probe_handler() which is used as the pre_handler for the kprobe inserted on kretprobe_implementation. This is the function that handles the details for calling the return probe handler function and returning control back at the original return address * Addition of arch_prepare_kretprobe() which is setup as the pre_handler for a kprobe registered at the beginning of the target function by kernel/kprobes.c so that a return probe instance can be setup when a caller enters the target function. (A return probe instance contains all the needed information for trampoline_probe_handler to do it's job.) * Hooks added to the exit path of a task so that we can cleanup any left-over return probe instances (i.e. if a task dies while inside a targeted function then the return probe instance was reserved at the beginning of the function but the function never returns so we need to mark the instance as unused.) Signed-off-by: Rusty Lynch <rusty.lynch@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 06:17:12 +08:00
{
trampoline_p.addr =
(kprobe_opcode_t *)((struct fnptr *)kretprobe_trampoline)->ip;
return register_kprobe(&trampoline_p);
}
int __kprobes arch_trampoline_kprobe(struct kprobe *p)
{
if (p->addr ==
(kprobe_opcode_t *)((struct fnptr *)kretprobe_trampoline)->ip)
return 1;
return 0;
}