[PATCH] Kprobes: Track kprobe on a per_cpu basis - ia64 changes (8a5c4dc5) · Commits · e / devices / android_kernel_xiaomi_markw

arch/ia64/kernel/kprobes.c

+45 −38

Original line number	Original line	Diff line number	Diff line
	@@ -38,13 +38,8 @@

	extern void jprobe_inst_return(void);		extern void jprobe_inst_return(void);

	/* kprobe_status settings */		DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
	#define KPROBE_HIT_ACTIVE 0x00000001		DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
	#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};		enum instruction_type {A, I, M, F, B, L, X, u};
	static enum instruction_type bundle_encoding[32][3] = {		static enum instruction_type bundle_encoding[32][3] = {
	@@ -313,21 +308,22 @@ static int __kprobes valid_kprobe_addr(int template, int slot,
	return 0;		return 0;
	}		}

	static inline void save_previous_kprobe(void)		static inline void save_previous_kprobe(struct kprobe_ctlblk *kcb)
	{		{
	kprobe_prev = current_kprobe;		kcb->prev_kprobe.kp = kprobe_running();
	kprobe_status_prev = kprobe_status;		kcb->prev_kprobe.status = kcb->kprobe_status;
	}		}

	static inline void restore_previous_kprobe(void)		static inline void restore_previous_kprobe(struct kprobe_ctlblk *kcb)
	{		{
	current_kprobe = kprobe_prev;		__get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp;
	kprobe_status = kprobe_status_prev;		kcb->kprobe_status = kcb->prev_kprobe.status;
	}		}

	static inline void set_current_kprobe(struct kprobe *p)		static inline void set_current_kprobe(struct kprobe *p,
			struct kprobe_ctlblk *kcb)
	{		{
	current_kprobe = p;		__get_cpu_var(current_kprobe) = p;
	}		}

	static void kretprobe_trampoline(void)		static void kretprobe_trampoline(void)
	@@ -389,6 +385,7 @@ int __kprobes trampoline_probe_handler(struct kprobe p, struct pt_regs regs)
	BUG_ON(!orig_ret_address \|\| (orig_ret_address == trampoline_address));		BUG_ON(!orig_ret_address \|\| (orig_ret_address == trampoline_address));
	regs->cr_iip = orig_ret_address;		regs->cr_iip = orig_ret_address;

			reset_current_kprobe();
	unlock_kprobes();		unlock_kprobes();
	preempt_enable_no_resched();		preempt_enable_no_resched();

	@@ -606,12 +603,13 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
	int ret = 0;		int ret = 0;
	struct pt_regs *regs = args->regs;		struct pt_regs *regs = args->regs;
	kprobe_opcode_t addr = (kprobe_opcode_t )instruction_pointer(regs);		kprobe_opcode_t addr = (kprobe_opcode_t )instruction_pointer(regs);
			struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();

	/* Handle recursion cases */		/* Handle recursion cases */
	if (kprobe_running()) {		if (kprobe_running()) {
	p = get_kprobe(addr);		p = get_kprobe(addr);
	if (p) {		if (p) {
	if ( (kprobe_status == KPROBE_HIT_SS) &&		if ((kcb->kprobe_status == KPROBE_HIT_SS) &&
	(p->ainsn.inst_flag == INST_FLAG_BREAK_INST)) {		(p->ainsn.inst_flag == INST_FLAG_BREAK_INST)) {
	ia64_psr(regs)->ss = 0;		ia64_psr(regs)->ss = 0;
	unlock_kprobes();		unlock_kprobes();
	@@ -623,17 +621,17 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
	* just single step on the instruction of the new probe		* just single step on the instruction of the new probe
	* without calling any user handlers.		* without calling any user handlers.
	*/		*/
	save_previous_kprobe();		save_previous_kprobe(kcb);
	set_current_kprobe(p);		set_current_kprobe(p, kcb);
	p->nmissed++;		p->nmissed++;
	prepare_ss(p, regs);		prepare_ss(p, regs);
	kprobe_status = KPROBE_REENTER;		kcb->kprobe_status = KPROBE_REENTER;
	return 1;		return 1;
	} else if (args->err == __IA64_BREAK_JPROBE) {		} else if (args->err == __IA64_BREAK_JPROBE) {
	/*		/*
	* jprobe instrumented function just completed		* jprobe instrumented function just completed
	*/		*/
	p = current_kprobe;		p = __get_cpu_var(current_kprobe);
	if (p->break_handler && p->break_handler(p, regs)) {		if (p->break_handler && p->break_handler(p, regs)) {
	goto ss_probe;		goto ss_probe;
	}		}
	@@ -668,8 +666,8 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
	* in post_kprobes_handler()		* in post_kprobes_handler()
	*/		*/
	preempt_disable();		preempt_disable();
	kprobe_status = KPROBE_HIT_ACTIVE;		set_current_kprobe(p, kcb);
	set_current_kprobe(p);		kcb->kprobe_status = KPROBE_HIT_ACTIVE;

	if (p->pre_handler && p->pre_handler(p, regs))		if (p->pre_handler && p->pre_handler(p, regs))
	/*		/*
	@@ -681,7 +679,7 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)

	ss_probe:		ss_probe:
	prepare_ss(p, regs);		prepare_ss(p, regs);
	kprobe_status = KPROBE_HIT_SS;		kcb->kprobe_status = KPROBE_HIT_SS;
	return 1;		return 1;

	no_kprobe:		no_kprobe:
	@@ -690,22 +688,25 @@ no_kprobe:

	static int __kprobes post_kprobes_handler(struct pt_regs *regs)		static int __kprobes post_kprobes_handler(struct pt_regs *regs)
	{		{
	if (!kprobe_running())		struct kprobe *cur = kprobe_running();
			struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();

			if (!cur)
	return 0;		return 0;

	if ((kprobe_status != KPROBE_REENTER) && current_kprobe->post_handler) {		if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
	kprobe_status = KPROBE_HIT_SSDONE;		kcb->kprobe_status = KPROBE_HIT_SSDONE;
	current_kprobe->post_handler(current_kprobe, regs, 0);		cur->post_handler(cur, regs, 0);
	}		}

	resume_execution(current_kprobe, regs);		resume_execution(cur, regs);

	/Restore back the original saved kprobes variables and continue. /		/Restore back the original saved kprobes variables and continue. /
	if (kprobe_status == KPROBE_REENTER) {		if (kcb->kprobe_status == KPROBE_REENTER) {
	restore_previous_kprobe();		restore_previous_kprobe(kcb);
	goto out;		goto out;
	}		}
			reset_current_kprobe();
	unlock_kprobes();		unlock_kprobes();

	out:		out:
	@@ -715,15 +716,18 @@ out:

	static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr)		static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr)
	{		{
	if (!kprobe_running())		struct kprobe *cur = kprobe_running();
			struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();

			if (!cur)
	return 0;		return 0;

	if (current_kprobe->fault_handler &&		if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
	current_kprobe->fault_handler(current_kprobe, regs, trapnr))
	return 1;		return 1;

	if (kprobe_status & KPROBE_HIT_SS) {		if (kcb->kprobe_status & KPROBE_HIT_SS) {
	resume_execution(current_kprobe, regs);		resume_execution(cur, regs);
			reset_current_kprobe();
	unlock_kprobes();		unlock_kprobes();
	preempt_enable_no_resched();		preempt_enable_no_resched();
	}		}
	@@ -761,9 +765,10 @@ int __kprobes setjmp_pre_handler(struct kprobe p, struct pt_regs regs)
	{		{
	struct jprobe *jp = container_of(p, struct jprobe, kp);		struct jprobe *jp = container_of(p, struct jprobe, kp);
	unsigned long addr = ((struct fnptr *)(jp->entry))->ip;		unsigned long addr = ((struct fnptr *)(jp->entry))->ip;
			struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();

	/* save architectural state */		/* save architectural state */
	jprobe_saved_regs = *regs;		kcb->jprobe_saved_regs = *regs;

	/* after rfi, execute the jprobe instrumented function */		/* after rfi, execute the jprobe instrumented function */
	regs->cr_iip = addr & ~0xFULL;		regs->cr_iip = addr & ~0xFULL;
	@@ -781,7 +786,9 @@ int __kprobes setjmp_pre_handler(struct kprobe p, struct pt_regs regs)

	int __kprobes 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;		struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();

			*regs = kcb->jprobe_saved_regs;
	return 1;		return 1;
	}		}

include/asm-ia64/kprobes.h

+13 −0

Original line number	Original line	Diff line number	Diff line
	@@ -26,6 +26,7 @@
	*/		*/
	#include <linux/types.h>		#include <linux/types.h>
	#include <linux/ptrace.h>		#include <linux/ptrace.h>
			#include <linux/percpu.h>
	#include <asm/break.h>		#include <asm/break.h>

	#define MAX_INSN_SIZE 16		#define MAX_INSN_SIZE 16
	@@ -62,6 +63,18 @@ typedef struct _bundle {
	} quad1;		} quad1;
	} __attribute__((__aligned__(16))) bundle_t;		} __attribute__((__aligned__(16))) bundle_t;

			struct prev_kprobe {
			struct kprobe *kp;
			unsigned long status;
			};

			/* per-cpu kprobe control block */
			struct kprobe_ctlblk {
			unsigned long kprobe_status;
			struct pt_regs jprobe_saved_regs;
			struct prev_kprobe prev_kprobe;
			};

	#define JPROBE_ENTRY(pentry) (kprobe_opcode_t *)pentry		#define JPROBE_ENTRY(pentry) (kprobe_opcode_t *)pentry

	#define ARCH_SUPPORTS_KRETPROBES		#define ARCH_SUPPORTS_KRETPROBES