s390/test_unwind: add program check context tests (de6921cc) · Commits · 戴 / test

arch/s390/lib/test_unwind.c

+47 −0

Original line number	Diff line number	Diff line
		@@ -10,6 +10,7 @@
		#include <linux/kthread.h>
		#include <linux/module.h>
		#include <linux/string.h>
		#include <linux/kprobes.h>
		#include <linux/wait.h>
		#include <asm/irq.h>
		#include <asm/delay.h>
		@@ -119,6 +120,7 @@ static struct unwindme *unwindme;
		#define UWM_CALLER 0x8 /* Unwind starting from caller. */
		#define UWM_SWITCH_STACK 0x10 /* Use CALL_ON_STACK. */
		#define UWM_IRQ 0x20 /* Unwind from irq context. */
		#define UWM_PGM 0x40 /* Unwind from program check handler. */

		static __always_inline unsigned long get_psw_addr(void)
		{
		@@ -130,6 +132,17 @@ static __always_inline unsigned long get_psw_addr(void)
		return psw_addr;
		}

		#ifdef CONFIG_KPROBES
		static int pgm_pre_handler(struct kprobe p, 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;
		}
		#endif

		/* This function may or may not appear in the backtrace. */
		static noinline int unwindme_func4(struct unwindme *u)
		{
		@@ -140,6 +153,34 @@ static noinline int unwindme_func4(struct unwindme *u)
		wait_event(u->task_wq, kthread_should_park());
		kthread_parkme();
		return 0;
		#ifdef CONFIG_KPROBES
		} else if (u->flags & UWM_PGM) {
		struct kprobe kp;
		int ret;

		unwindme = u;
		memset(&kp, 0, sizeof(kp));
		kp.symbol_name = "do_report_trap";
		kp.pre_handler = pgm_pre_handler;
		ret = register_kprobe(&kp);
		if (ret < 0) {
		pr_err("register_kprobe failed %d\n", ret);
		return -EINVAL;
		}

		/*
		* trigger specification exception
		*/
		asm volatile(
		" mvcl %%r1,%%r1\n"
		"0: nopr %%r7\n"
		EX_TABLE(0b, 0b)
		:);

		unregister_kprobe(&kp);
		unwindme = NULL;
		return u->ret;
		#endif
		} else {
		struct pt_regs regs;

		@@ -286,6 +327,12 @@ do { \
		TEST(UWM_IRQ \| UWM_CALLER \| UWM_SP);
		TEST(UWM_IRQ \| UWM_CALLER \| UWM_SP \| UWM_REGS);
		TEST(UWM_IRQ \| UWM_CALLER \| UWM_SP \| UWM_REGS \| UWM_SWITCH_STACK);
		#ifdef CONFIG_KPROBES
		TEST(UWM_PGM);
		TEST(UWM_PGM \| UWM_SP);
		TEST(UWM_PGM \| UWM_REGS);
		TEST(UWM_PGM \| UWM_SP \| UWM_REGS);
		#endif
		#undef TEST

		return ret;

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