[PATCH] Kprobes: prevent possible race conditions ia64 changes

This patch contains the ia64 architecture specific changes to prevent the
possible race conditions.
Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/ia64/kernel/jprobes.S

@@ -49,6 +49,7 @@
 	/*
 	 * void jprobe_break(void)
 	 */
+	.section .kprobes.text, "ax"
 ENTRY(jprobe_break)
 	break.m 0x80300
 END(jprobe_break)

arch/ia64/kernel/kprobes.c

@@ -87,8 +87,10 @@ static enum instruction_type bundle_encoding[32][3] = {
  * 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)
+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;
@@ -126,8 +128,10 @@ static void update_kprobe_inst_flag(uint template, uint  slot, uint major_opcode
  * 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)
+static int __kprobes unsupported_inst(uint template, uint  slot,
+				      uint major_opcode,
+				      unsigned long kprobe_inst,
+				      struct kprobe *p)
 {
 	unsigned long addr = (unsigned long)p->addr;
 
@@ -168,8 +172,9 @@ static int unsupported_inst(uint template, uint  slot, uint major_opcode,
  * 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)
+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;
@@ -201,8 +206,10 @@ out:
  * 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)
+static void __kprobes 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;
@@ -271,7 +278,8 @@ static inline int in_ivt_functions(unsigned long addr)
 		&& addr < (unsigned long)__end_ivt_text);
 }
 
-static int valid_kprobe_addr(int template, int slot, unsigned long addr)
+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 "
@@ -323,7 +331,7 @@ static void kretprobe_trampoline(void)
  *    - cleanup by marking the instance as unused
  *    - long jump back to the original return address
  */
-int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
+int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
 {
 	struct kretprobe_instance *ri = NULL;
 	struct hlist_head *head;
@@ -381,7 +389,8 @@ int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
         return 1;
 }
 
-void arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs)
+void __kprobes arch_prepare_kretprobe(struct kretprobe *rp,
+				      struct pt_regs *regs)
 {
 	struct kretprobe_instance *ri;
 
@@ -399,7 +408,7 @@ void arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs)
 	}
 }
 
-int arch_prepare_kprobe(struct kprobe *p)
+int __kprobes arch_prepare_kprobe(struct kprobe *p)
 {
 	unsigned long addr = (unsigned long) p->addr;
 	unsigned long *kprobe_addr = (unsigned long *)(addr & ~0xFULL);
@@ -430,7 +439,7 @@ int arch_prepare_kprobe(struct kprobe *p)
 	return 0;
 }
 
-void arch_arm_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;
@@ -439,7 +448,7 @@ void arch_arm_kprobe(struct kprobe *p)
 	flush_icache_range(arm_addr, arm_addr + sizeof(bundle_t));
 }
 
-void arch_disarm_kprobe(struct kprobe *p)
+void __kprobes arch_disarm_kprobe(struct kprobe *p)
 {
 	unsigned long addr = (unsigned long)p->addr;
 	unsigned long arm_addr = addr & ~0xFULL;
@@ -449,7 +458,7 @@ void arch_disarm_kprobe(struct kprobe *p)
 	flush_icache_range(arm_addr, arm_addr + sizeof(bundle_t));
 }
 
-void arch_remove_kprobe(struct kprobe *p)
+void __kprobes arch_remove_kprobe(struct kprobe *p)
 {
 }
 
@@ -461,7 +470,7 @@ void arch_remove_kprobe(struct kprobe *p)
  * 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)
+static void __kprobes 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;
@@ -528,7 +537,7 @@ turn_ss_off:
   	ia64_psr(regs)->ss = 0;
 }
 
-static void prepare_ss(struct kprobe *p, struct pt_regs *regs)
+static void __kprobes 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;
@@ -545,7 +554,7 @@ static void prepare_ss(struct kprobe *p, struct pt_regs *regs)
 	ia64_psr(regs)->ss = 1;
 }
 
-static int pre_kprobes_handler(struct die_args *args)
+static int __kprobes pre_kprobes_handler(struct die_args *args)
 {
 	struct kprobe *p;
 	int ret = 0;
@@ -616,7 +625,7 @@ no_kprobe:
 	return ret;
 }
 
-static int post_kprobes_handler(struct pt_regs *regs)
+static int __kprobes post_kprobes_handler(struct pt_regs *regs)
 {
 	if (!kprobe_running())
 		return 0;
@@ -641,7 +650,7 @@ out:
 	return 1;
 }
 
-static int kprobes_fault_handler(struct pt_regs *regs, int trapnr)
+static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr)
 {
 	if (!kprobe_running())
 		return 0;
@@ -659,8 +668,8 @@ static int kprobes_fault_handler(struct pt_regs *regs, int trapnr)
 	return 0;
 }
 
-int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val,
-			     void *data)
+int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
+				       unsigned long val, void *data)
 {
 	struct die_args *args = (struct die_args *)data;
 	switch(val) {
@@ -681,7 +690,7 @@ int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val,
 	return NOTIFY_DONE;
 }
 
-int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
+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;
@@ -703,7 +712,7 @@ int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
 	return 1;
 }
 
-int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
+int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
 {
 	*regs = jprobe_saved_regs;
 	return 1;

arch/ia64/kernel/traps.c

@@ -15,6 +15,7 @@
 #include <linux/vt_kern.h>		/* For unblank_screen() */
 #include <linux/module.h>       /* for EXPORT_SYMBOL */
 #include <linux/hardirq.h>
+#include <linux/kprobes.h>
 
 #include <asm/fpswa.h>
 #include <asm/ia32.h>
@@ -122,7 +123,7 @@ die_if_kernel (char *str, struct pt_regs *regs, long err)
 }
 
 void
-ia64_bad_break (unsigned long break_num, struct pt_regs *regs)
+__kprobes ia64_bad_break (unsigned long break_num, struct pt_regs *regs)
 {
 	siginfo_t siginfo;
 	int sig, code;
@@ -444,7 +445,7 @@ ia64_illegal_op_fault (unsigned long ec, long arg1, long arg2, long arg3,
 	return rv;
 }
 
-void
+void __kprobes
 ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 	    unsigned long iim, unsigned long itir, long arg5, long arg6,
 	    long arg7, struct pt_regs regs)

arch/ia64/kernel/vmlinux.lds.S

@@ -48,6 +48,7 @@ SECTIONS
 	*(.text)
 	SCHED_TEXT
 	LOCK_TEXT
+	KPROBES_TEXT
 	*(.gnu.linkonce.t*)
     }
   .text2 : AT(ADDR(.text2) - LOAD_OFFSET)

arch/ia64/lib/flush.S

@@ -20,6 +20,7 @@
 	 *
 	 *	Note: "in0" and "in1" are preserved for debugging purposes.
 	 */
+	.section .kprobes.text,"ax"
 GLOBAL_ENTRY(flush_icache_range)
 
 	.prologue

arch/ia64/mm/fault.c

@@ -9,6 +9,7 @@
 #include <linux/mm.h>
 #include <linux/smp_lock.h>
 #include <linux/interrupt.h>
+#include <linux/kprobes.h>
 
 #include <asm/pgtable.h>
 #include <asm/processor.h>
@@ -76,7 +77,7 @@ mapped_kernel_page_is_present (unsigned long address)
 	return pte_present(pte);
 }
 
-void
+void __kprobes
 ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *regs)
 {
 	int signal = SIGSEGV, code = SEGV_MAPERR;