From 08ed38b68099f2a492196414b08a7f5dd8dc3537 Mon Sep 17 00:00:00 2001
From: Tony Luck <tony.luck@intel.com>
Date: Tue, 14 Nov 2006 09:33:38 -0800
Subject: [PATCH] [IA64] enable trap code on slot 1
Because slot 1 of one instr bundle crosses border of two consecutive
8-bytes, kprobe on slot 1 is disabled. This patch enables kprobe on
slot1, it only replaces higher 8-bytes of the instruction bundle and
changes the exception code to ignore the low 12 bits of the break
number (which is across the border in the lower 8-bytes of the bundle).
For those instructions which must execute regardless qp bits,
kprobe on slot 1 is still disabled.
Signed-off-by: bibo,mao <bibo.mao@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
---
arch/ia64/kernel/jprobes.S | 3 ++-
arch/ia64/kernel/kprobes.c | 51 +++++++++++++++++++++++++++-----------
include/asm-ia64/break.h | 4 +--
include/asm-ia64/kprobes.h | 1 +
4 files changed, 42 insertions(+), 17 deletions(-)
diff --git a/arch/ia64/kernel/jprobes.S b/arch/ia64/kernel/jprobes.S
index 5cd6226f44f2..621630256c4a 100644
--- a/arch/ia64/kernel/jprobes.S
+++ b/arch/ia64/kernel/jprobes.S
@@ -45,13 +45,14 @@
* to the correct location.
*/
#include <asm/asmmacro.h>
+#include <asm-ia64/break.h>
/*
* void jprobe_break(void)
*/
.section .kprobes.text, "ax"
ENTRY(jprobe_break)
- break.m 0x80300
+ break.m __IA64_BREAK_JPROBE
END(jprobe_break)
/*
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 76e778951e20..8406d24d516b 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -88,6 +88,7 @@ static void __kprobes update_kprobe_inst_flag(uint template, uint slot,
{
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
@@ -296,12 +297,6 @@ static int __kprobes valid_kprobe_addr(int template, int slot,
return -EINVAL;
}
- if (slot == 1 && bundle_encoding[template][1] != L) {
- printk(KERN_WARNING "Inserting kprobes on slot #1 "
- "is not supported\n");
- return -EINVAL;
- }
-
return 0;
}
@@ -458,23 +453,49 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
void __kprobes arch_arm_kprobe(struct kprobe *p)
{
- unsigned long addr = (unsigned long)p->addr;
- unsigned long arm_addr = addr & ~0xFULL;
+ 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));
- memcpy((char *)arm_addr, &p->opcode, 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 addr = (unsigned long)p->addr;
- unsigned long arm_addr = addr & ~0xFULL;
+ 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 */
- memcpy((char *) arm_addr, (char *) p->ainsn.insn,
- sizeof(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));
}
@@ -807,7 +828,9 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
switch(val) {
case DIE_BREAK:
/* err is break number from ia64_bad_break() */
- if (args->err == 0x80200 || args->err == 0x80300 || args->err == 0)
+ if ((args->err >> 12) == (__IA64_BREAK_KPROBE >> 12)
+ || args->err == __IA64_BREAK_JPROBE
+ || args->err == 0)
if (pre_kprobes_handler(args))
ret = NOTIFY_STOP;
break;
diff --git a/include/asm-ia64/break.h b/include/asm-ia64/break.h
index 8167828edc4b..f03402039896 100644
--- a/include/asm-ia64/break.h
+++ b/include/asm-ia64/break.h
@@ -12,8 +12,8 @@
* OS-specific debug break numbers:
*/
#define __IA64_BREAK_KDB 0x80100
-#define __IA64_BREAK_KPROBE 0x80200
-#define __IA64_BREAK_JPROBE 0x80300
+#define __IA64_BREAK_KPROBE 0x81000 /* .. 0x81fff */
+#define __IA64_BREAK_JPROBE 0x82000
/*
* OS-specific break numbers:
diff --git a/include/asm-ia64/kprobes.h b/include/asm-ia64/kprobes.h
index 1b45b71c79b9..828ae00e47c1 100644
--- a/include/asm-ia64/kprobes.h
+++ b/include/asm-ia64/kprobes.h
@@ -115,6 +115,7 @@ struct arch_specific_insn {
#define INST_FLAG_BREAK_INST 4
unsigned long inst_flag;
unsigned short target_br_reg;
+ unsigned short slot;
};
extern int kprobe_exceptions_notify(struct notifier_block *self,