iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

s390/test_unwind: add kretprobe tests

Browse Source 
Add tests to verify that s390 kretprobes maintain a correct stack
chain and ensure their proper function.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Tobias Huschle <huschle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Tobias Huschle 2022-02-24 16:14:21 +01:00 committed by Vasily Gorbik
parent 63bf38ff5b
commit c65f677b62
1 changed files with 56 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
arch/s390/lib/test_unwind.c
View File

@ -132,6 +132,7 @@ 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. */
static __always_inline unsigned long get_psw_addr(void)
{
@ -143,6 +144,55 @@ static __always_inline unsigned long get_psw_addr(void)
return psw_addr;
}
static int kretprobe_ret_handler(struct kretprobe_instance *ri, struct pt_regs *regs)
{
struct unwindme *u = unwindme;
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)
{
asm volatile(" nop\n");
}
static noinline void test_unwind_kretprobed_func_caller(void)
{
test_unwind_kretprobed_func();
}
static int test_unwind_kretprobe(struct unwindme *u)
{
int ret;
struct kretprobe my_kretprobe;
if (!IS_ENABLED(CONFIG_KPROBES))
kunit_skip(current_test, "requires CONFIG_KPROBES");
u->ret = -1; /* make sure kprobe is called */
unwindme = u;
memset(&my_kretprobe, 0, sizeof(my_kretprobe));
my_kretprobe.handler = kretprobe_ret_handler;
my_kretprobe.maxactive = 1;
my_kretprobe.kp.addr = (kprobe_opcode_t *)test_unwind_kretprobed_func;
ret = register_kretprobe(&my_kretprobe);
if (ret < 0) {
kunit_err(current_test, "register_kretprobe failed %d\n", ret);
return -EINVAL;
}
test_unwind_kretprobed_func_caller();
unregister_kretprobe(&my_kretprobe);
unwindme = NULL;
return u->ret;
}
static int kprobe_pre_handler(struct kprobe *p, struct pt_regs *regs)
{
struct unwindme *u = unwindme;
@ -254,6 +304,8 @@ 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)) {
return test_unwind_kretprobe(u);
} else if (u->flags & UWM_FTRACE) {
return test_unwind_ftrace(u);
} else {
@ -396,6 +448,10 @@ static const struct test_params param_list[] = {
TEST_WITH_FLAGS(UWM_FTRACE | UWM_SP),
TEST_WITH_FLAGS(UWM_FTRACE | UWM_REGS),
TEST_WITH_FLAGS(UWM_FTRACE | UWM_SP | UWM_REGS),
TEST_WITH_FLAGS(UWM_KRETPROBE),
TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_SP),
TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_REGS),
TEST_WITH_FLAGS(UWM_KRETPROBE | UWM_SP | UWM_REGS),
};
/*