Commit 0b452520 authored by Vasily Gorbik's avatar Vasily Gorbik
Browse files

s390/test_unwind: extend kretprobe test 



Verify unwinding from kretprobed function.

Reviewed-by: default avatarTobias Huschle <huschle@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent a7e196f5

arch/s390/lib/test_unwind.c

+33 −16
Original line number Diff line number Diff line
@@ -132,36 +132,50 @@ static struct unwindme *unwindme; 
#define UWM_PGM			0x40	/* Unwind from program check handler */

#define UWM_KPROBE_ON_FTRACE	0x80	/* Unwind from kprobe handler called via ftrace. */

#define UWM_FTRACE		0x100	/* Unwind from ftrace handler. */

#define UWM_KRETPROBE		0x200	/* Unwind kretprobe handlers. */

#define UWM_KRETPROBE		0x200	/* Unwind through kretprobed function. */

#define UWM_KRETPROBE_HANDLER	0x400	/* Unwind from kretprobe handler. */



static __always_inline unsigned long get_psw_addr(void)

static __always_inline struct pt_regs fake_pt_regs(void)

{

	unsigned long psw_addr;

	struct pt_regs regs;



	memset(&regs, 0, sizeof(regs));

	regs.gprs[15] = current_stack_pointer();



	asm volatile(

		"basr	%[psw_addr],0\n"

		: [psw_addr] "=d" (psw_addr));

	return psw_addr;

		: [psw_addr] "=d" (regs.psw.addr));

	return regs;

}



static int kretprobe_ret_handler(struct kretprobe_instance *ri, struct pt_regs *regs)

{

	struct unwindme *u = unwindme;



	if (!(u->flags & UWM_KRETPROBE_HANDLER))

		return 0;



	u->ret = test_unwind(NULL, (u->flags & UWM_REGS) ? regs : NULL,

			     (u->flags & UWM_SP) ? u->sp : 0);



	return 0;

}



static noinline notrace void test_unwind_kretprobed_func(void)

static noinline notrace int test_unwind_kretprobed_func(struct unwindme *u)

{

	asm volatile("	nop\n");

	struct pt_regs regs;



	if (!(u->flags & UWM_KRETPROBE))

		return 0;



	regs = fake_pt_regs();

	return test_unwind(NULL, (u->flags & UWM_REGS) ? &regs : NULL,

			   (u->flags & UWM_SP) ? u->sp : 0);

}



static noinline void test_unwind_kretprobed_func_caller(void)

static noinline int test_unwind_kretprobed_func_caller(struct unwindme *u)

{

	test_unwind_kretprobed_func();

	return test_unwind_kretprobed_func(u);

}



static int test_unwind_kretprobe(struct unwindme *u)
@@ -187,10 +201,12 @@ static int test_unwind_kretprobe(struct unwindme *u) 
		return -EINVAL;

	}



	test_unwind_kretprobed_func_caller();

	ret = test_unwind_kretprobed_func_caller(u);

	unregister_kretprobe(&my_kretprobe);

	unwindme = NULL;

	return u->ret;

	if (u->flags & UWM_KRETPROBE_HANDLER)

		ret = u->ret;

	return ret;

}



static int kprobe_pre_handler(struct kprobe *p, struct pt_regs *regs)
@@ -304,16 +320,13 @@ static noinline int unwindme_func4(struct unwindme *u) 
		return 0;

	} else if (u->flags & (UWM_PGM | UWM_KPROBE_ON_FTRACE)) {

		return test_unwind_kprobe(u);

	} else if (u->flags & (UWM_KRETPROBE)) {

	} else if (u->flags & (UWM_KRETPROBE | UWM_KRETPROBE_HANDLER)) {

		return test_unwind_kretprobe(u);

	} else if (u->flags & UWM_FTRACE) {

		return test_unwind_ftrace(u);

	} else {

		struct pt_regs regs;

		struct pt_regs regs = fake_pt_regs();



		memset(&regs, 0, sizeof(regs));

		regs.psw.addr = get_psw_addr();

		regs.gprs[15] = current_stack_pointer();

		return test_unwind(NULL,

				   (u->flags & UWM_REGS) ? &regs : NULL,

				   (u->flags & UWM_SP) ? u->sp : 0);
@@ -452,6 +465,10 @@ static const struct test_params param_list[] = { 
	TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_SP),

	TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_REGS),

	TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_SP | UWM_REGS),

	TEST_WITH_FLAGS(UWM_KRETPROBE_HANDLER),

	TEST_WITH_FLAGS(UWM_KRETPROBE_HANDLER | UWM_SP),

	TEST_WITH_FLAGS(UWM_KRETPROBE_HANDLER | UWM_REGS),

	TEST_WITH_FLAGS(UWM_KRETPROBE_HANDLER | UWM_SP | UWM_REGS),

};



/*