Linux Audio

Check our new training course

Loading...
v3.15
 
  1/*
  2 *  S390 version
  3 *    Copyright IBM Corp. 1999, 2000
  4 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
  5 *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
  6 *
  7 *  Derived from "arch/i386/kernel/traps.c"
  8 *    Copyright (C) 1991, 1992 Linus Torvalds
  9 */
 10
 11/*
 12 * 'Traps.c' handles hardware traps and faults after we have saved some
 13 * state in 'asm.s'.
 14 */
 
 
 15#include <linux/kprobes.h>
 16#include <linux/kdebug.h>
 17#include <linux/module.h>
 
 18#include <linux/ptrace.h>
 19#include <linux/sched.h>
 
 20#include <linux/mm.h>
 
 
 
 
 
 
 21#include "entry.h"
 22
 23int show_unhandled_signals = 1;
 24
 25static inline void __user *get_trap_ip(struct pt_regs *regs)
 26{
 27#ifdef CONFIG_64BIT
 28	unsigned long address;
 29
 30	if (regs->int_code & 0x200)
 31		address = *(unsigned long *)(current->thread.trap_tdb + 24);
 32	else
 33		address = regs->psw.addr;
 34	return (void __user *)
 35		((address - (regs->int_code >> 16)) & PSW_ADDR_INSN);
 36#else
 37	return (void __user *)
 38		((regs->psw.addr - (regs->int_code >> 16)) & PSW_ADDR_INSN);
 39#endif
 40}
 41
 42static inline void report_user_fault(struct pt_regs *regs, int signr)
 43{
 44	if ((task_pid_nr(current) > 1) && !show_unhandled_signals)
 45		return;
 46	if (!unhandled_signal(current, signr))
 47		return;
 48	if (!printk_ratelimit())
 49		return;
 50	printk("User process fault: interruption code 0x%X ", regs->int_code);
 51	print_vma_addr("in ", regs->psw.addr & PSW_ADDR_INSN);
 52	printk("\n");
 53	show_regs(regs);
 54}
 55
 56int is_valid_bugaddr(unsigned long addr)
 57{
 58	return 1;
 59}
 60
 61static void __kprobes do_trap(struct pt_regs *regs,
 62			      int si_signo, int si_code, char *str)
 63{
 64	siginfo_t info;
 65
 66	if (notify_die(DIE_TRAP, str, regs, 0,
 67		       regs->int_code, si_signo) == NOTIFY_STOP)
 68		return;
 69
 70	if (user_mode(regs)) {
 71		info.si_signo = si_signo;
 72		info.si_errno = 0;
 73		info.si_code = si_code;
 74		info.si_addr = get_trap_ip(regs);
 75		force_sig_info(si_signo, &info, current);
 76		report_user_fault(regs, si_signo);
 77        } else {
 78                const struct exception_table_entry *fixup;
 79                fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
 80                if (fixup)
 81			regs->psw.addr = extable_fixup(fixup) | PSW_ADDR_AMODE;
 82		else {
 83			enum bug_trap_type btt;
 84
 85			btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
 86			if (btt == BUG_TRAP_TYPE_WARN)
 87				return;
 88			die(regs, str);
 89		}
 90        }
 91}
 92
 93void __kprobes do_per_trap(struct pt_regs *regs)
 94{
 95	siginfo_t info;
 
 
 
 
 
 96
 
 
 97	if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
 98		return;
 99	if (!current->ptrace)
100		return;
101	info.si_signo = SIGTRAP;
102	info.si_errno = 0;
103	info.si_code = TRAP_HWBKPT;
104	info.si_addr =
105		(void __force __user *) current->thread.per_event.address;
106	force_sig_info(SIGTRAP, &info, current);
107}
 
108
109void default_trap_handler(struct pt_regs *regs)
110{
111	if (user_mode(regs)) {
112		report_user_fault(regs, SIGSEGV);
113		do_exit(SIGSEGV);
114	} else
115		die(regs, "Unknown program exception");
116}
117
118#define DO_ERROR_INFO(name, signr, sicode, str) \
119void name(struct pt_regs *regs)			\
120{						\
121	do_trap(regs, signr, sicode, str);	\
122}
123
124DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
125	      "addressing exception")
126DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
127	      "execute exception")
128DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
129	      "fixpoint divide exception")
130DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
131	      "fixpoint overflow exception")
132DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
133	      "HFP overflow exception")
134DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
135	      "HFP underflow exception")
136DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
137	      "HFP significance exception")
138DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
139	      "HFP divide exception")
140DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
141	      "HFP square root exception")
142DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
143	      "operand exception")
144DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
145	      "privileged operation")
146DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
147	      "special operation exception")
148DO_ERROR_INFO(translation_exception, SIGILL, ILL_ILLOPN,
149	      "translation exception")
150
151#ifdef CONFIG_64BIT
152DO_ERROR_INFO(transaction_exception, SIGILL, ILL_ILLOPN,
153	      "transaction constraint exception")
154#endif
155
156static inline void do_fp_trap(struct pt_regs *regs, int fpc)
157{
158	int si_code = 0;
159	/* FPC[2] is Data Exception Code */
160	if ((fpc & 0x00000300) == 0) {
161		/* bits 6 and 7 of DXC are 0 iff IEEE exception */
162		if (fpc & 0x8000) /* invalid fp operation */
163			si_code = FPE_FLTINV;
164		else if (fpc & 0x4000) /* div by 0 */
165			si_code = FPE_FLTDIV;
166		else if (fpc & 0x2000) /* overflow */
167			si_code = FPE_FLTOVF;
168		else if (fpc & 0x1000) /* underflow */
169			si_code = FPE_FLTUND;
170		else if (fpc & 0x0800) /* inexact */
171			si_code = FPE_FLTRES;
172	}
173	do_trap(regs, SIGFPE, si_code, "floating point exception");
174}
175
176void __kprobes illegal_op(struct pt_regs *regs)
 
 
 
 
 
 
177{
178	siginfo_t info;
179        __u8 opcode[6];
180	__u16 __user *location;
 
181	int signal = 0;
182
183	location = get_trap_ip(regs);
184
185	if (user_mode(regs)) {
186		if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
187			return;
188		if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
189			if (current->ptrace) {
190				info.si_signo = SIGTRAP;
191				info.si_errno = 0;
192				info.si_code = TRAP_BRKPT;
193				info.si_addr = location;
194				force_sig_info(SIGTRAP, &info, current);
195			} else
196				signal = SIGILL;
197#ifdef CONFIG_MATHEMU
198		} else if (opcode[0] == 0xb3) {
199			if (get_user(*((__u16 *) (opcode+2)), location+1))
200				return;
201			signal = math_emu_b3(opcode, regs);
202                } else if (opcode[0] == 0xed) {
203			if (get_user(*((__u32 *) (opcode+2)),
204				     (__u32 __user *)(location+1)))
205				return;
206			signal = math_emu_ed(opcode, regs);
207		} else if (*((__u16 *) opcode) == 0xb299) {
208			if (get_user(*((__u16 *) (opcode+2)), location+1))
209				return;
210			signal = math_emu_srnm(opcode, regs);
211		} else if (*((__u16 *) opcode) == 0xb29c) {
212			if (get_user(*((__u16 *) (opcode+2)), location+1))
213				return;
214			signal = math_emu_stfpc(opcode, regs);
215		} else if (*((__u16 *) opcode) == 0xb29d) {
216			if (get_user(*((__u16 *) (opcode+2)), location+1))
217				return;
218			signal = math_emu_lfpc(opcode, regs);
219#endif
220		} else
221			signal = SIGILL;
222	} else {
223		/*
224		 * If we get an illegal op in kernel mode, send it through the
225		 * kprobes notifier. If kprobes doesn't pick it up, SIGILL
226		 */
 
 
227		if (notify_die(DIE_BPT, "bpt", regs, 0,
228			       3, SIGTRAP) != NOTIFY_STOP)
229			signal = SIGILL;
230	}
231
232#ifdef CONFIG_MATHEMU
233        if (signal == SIGFPE)
234		do_fp_trap(regs, current->thread.fp_regs.fpc);
235	else if (signal == SIGSEGV)
236		do_trap(regs, signal, SEGV_MAPERR, "user address fault");
237	else
238#endif
239	if (signal)
240		do_trap(regs, signal, ILL_ILLOPC, "illegal operation");
241}
 
242
243
244#ifdef CONFIG_MATHEMU
245void specification_exception(struct pt_regs *regs)
246{
247        __u8 opcode[6];
248	__u16 __user *location = NULL;
249	int signal = 0;
250
251	location = (__u16 __user *) get_trap_ip(regs);
252
253	if (user_mode(regs)) {
254		get_user(*((__u16 *) opcode), location);
255		switch (opcode[0]) {
256		case 0x28: /* LDR Rx,Ry   */
257			signal = math_emu_ldr(opcode);
258			break;
259		case 0x38: /* LER Rx,Ry   */
260			signal = math_emu_ler(opcode);
261			break;
262		case 0x60: /* STD R,D(X,B) */
263			get_user(*((__u16 *) (opcode+2)), location+1);
264			signal = math_emu_std(opcode, regs);
265			break;
266		case 0x68: /* LD R,D(X,B) */
267			get_user(*((__u16 *) (opcode+2)), location+1);
268			signal = math_emu_ld(opcode, regs);
269			break;
270		case 0x70: /* STE R,D(X,B) */
271			get_user(*((__u16 *) (opcode+2)), location+1);
272			signal = math_emu_ste(opcode, regs);
273			break;
274		case 0x78: /* LE R,D(X,B) */
275			get_user(*((__u16 *) (opcode+2)), location+1);
276			signal = math_emu_le(opcode, regs);
277			break;
278		default:
279			signal = SIGILL;
280			break;
281                }
282        } else
283		signal = SIGILL;
284
285        if (signal == SIGFPE)
286		do_fp_trap(regs, current->thread.fp_regs.fpc);
287	else if (signal)
288		do_trap(regs, signal, ILL_ILLOPN, "specification exception");
289}
290#else
291DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
292	      "specification exception");
293#endif
294
295void data_exception(struct pt_regs *regs)
296{
297	__u16 __user *location;
298	int signal = 0;
299
300	location = get_trap_ip(regs);
 
 
 
301
302	if (MACHINE_HAS_IEEE)
303		asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
304
305#ifdef CONFIG_MATHEMU
306	else if (user_mode(regs)) {
307        	__u8 opcode[6];
308		get_user(*((__u16 *) opcode), location);
309		switch (opcode[0]) {
310		case 0x28: /* LDR Rx,Ry   */
311			signal = math_emu_ldr(opcode);
312			break;
313		case 0x38: /* LER Rx,Ry   */
314			signal = math_emu_ler(opcode);
315			break;
316		case 0x60: /* STD R,D(X,B) */
317			get_user(*((__u16 *) (opcode+2)), location+1);
318			signal = math_emu_std(opcode, regs);
319			break;
320		case 0x68: /* LD R,D(X,B) */
321			get_user(*((__u16 *) (opcode+2)), location+1);
322			signal = math_emu_ld(opcode, regs);
323			break;
324		case 0x70: /* STE R,D(X,B) */
325			get_user(*((__u16 *) (opcode+2)), location+1);
326			signal = math_emu_ste(opcode, regs);
327			break;
328		case 0x78: /* LE R,D(X,B) */
329			get_user(*((__u16 *) (opcode+2)), location+1);
330			signal = math_emu_le(opcode, regs);
331			break;
332		case 0xb3:
333			get_user(*((__u16 *) (opcode+2)), location+1);
334			signal = math_emu_b3(opcode, regs);
335			break;
336                case 0xed:
337			get_user(*((__u32 *) (opcode+2)),
338				 (__u32 __user *)(location+1));
339			signal = math_emu_ed(opcode, regs);
340			break;
341	        case 0xb2:
342			if (opcode[1] == 0x99) {
343				get_user(*((__u16 *) (opcode+2)), location+1);
344				signal = math_emu_srnm(opcode, regs);
345			} else if (opcode[1] == 0x9c) {
346				get_user(*((__u16 *) (opcode+2)), location+1);
347				signal = math_emu_stfpc(opcode, regs);
348			} else if (opcode[1] == 0x9d) {
349				get_user(*((__u16 *) (opcode+2)), location+1);
350				signal = math_emu_lfpc(opcode, regs);
351			} else
352				signal = SIGILL;
353			break;
354		default:
355			signal = SIGILL;
356			break;
357                }
358        }
359#endif 
360	if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
361		signal = SIGFPE;
362	else
363		signal = SIGILL;
364        if (signal == SIGFPE)
365		do_fp_trap(regs, current->thread.fp_regs.fpc);
366	else if (signal)
367		do_trap(regs, signal, ILL_ILLOPN, "data exception");
368}
369
370void space_switch_exception(struct pt_regs *regs)
371{
372	/* Set user psw back to home space mode. */
373	if (user_mode(regs))
374		regs->psw.mask |= PSW_ASC_HOME;
375	/* Send SIGILL. */
376	do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event");
377}
378
379void __kprobes kernel_stack_overflow(struct pt_regs * regs)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
380{
381	bust_spinlocks(1);
382	printk("Kernel stack overflow.\n");
383	show_regs(regs);
384	bust_spinlocks(0);
385	panic("Corrupt kernel stack, can't continue.");
386}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
387
388void __init trap_init(void)
389{
 
390	local_mcck_enable();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
391}
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  S390 version
  4 *    Copyright IBM Corp. 1999, 2000
  5 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
  6 *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
  7 *
  8 *  Derived from "arch/i386/kernel/traps.c"
  9 *    Copyright (C) 1991, 1992 Linus Torvalds
 10 */
 11
 12/*
 13 * 'Traps.c' handles hardware traps and faults after we have saved some
 14 * state in 'asm.s'.
 15 */
 16#include "asm/irqflags.h"
 17#include "asm/ptrace.h"
 18#include <linux/kprobes.h>
 19#include <linux/kdebug.h>
 20#include <linux/randomize_kstack.h>
 21#include <linux/extable.h>
 22#include <linux/ptrace.h>
 23#include <linux/sched.h>
 24#include <linux/sched/debug.h>
 25#include <linux/mm.h>
 26#include <linux/slab.h>
 27#include <linux/uaccess.h>
 28#include <linux/cpu.h>
 29#include <linux/entry-common.h>
 30#include <asm/fpu/api.h>
 31#include <asm/vtime.h>
 32#include "entry.h"
 33
 
 
 34static inline void __user *get_trap_ip(struct pt_regs *regs)
 35{
 
 36	unsigned long address;
 37
 38	if (regs->int_code & 0x200)
 39		address = current->thread.trap_tdb.data[3];
 40	else
 41		address = regs->psw.addr;
 42	return (void __user *) (address - (regs->int_code >> 16));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 43}
 44
 45int is_valid_bugaddr(unsigned long addr)
 46{
 47	return 1;
 48}
 49
 50void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
 
 51{
 
 
 
 
 
 
 52	if (user_mode(regs)) {
 53		force_sig_fault(si_signo, si_code, get_trap_ip(regs));
 54		report_user_fault(regs, si_signo, 0);
 
 
 
 
 55        } else {
 56                const struct exception_table_entry *fixup;
 57		fixup = s390_search_extables(regs->psw.addr);
 58		if (!fixup || !ex_handle(fixup, regs))
 
 
 
 
 
 
 
 59			die(regs, str);
 
 60        }
 61}
 62
 63static void do_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
 64{
 65	if (notify_die(DIE_TRAP, str, regs, 0,
 66		       regs->int_code, si_signo) == NOTIFY_STOP)
 67		return;
 68	do_report_trap(regs, si_signo, si_code, str);
 69}
 70NOKPROBE_SYMBOL(do_trap);
 71
 72void do_per_trap(struct pt_regs *regs)
 73{
 74	if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
 75		return;
 76	if (!current->ptrace)
 77		return;
 78	force_sig_fault(SIGTRAP, TRAP_HWBKPT,
 79		(void __force __user *) current->thread.per_event.address);
 
 
 
 
 80}
 81NOKPROBE_SYMBOL(do_per_trap);
 82
 83static void default_trap_handler(struct pt_regs *regs)
 84{
 85	if (user_mode(regs)) {
 86		report_user_fault(regs, SIGSEGV, 0);
 87		do_exit(SIGSEGV);
 88	} else
 89		die(regs, "Unknown program exception");
 90}
 91
 92#define DO_ERROR_INFO(name, signr, sicode, str) \
 93static void name(struct pt_regs *regs)		\
 94{						\
 95	do_trap(regs, signr, sicode, str);	\
 96}
 97
 98DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
 99	      "addressing exception")
100DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
101	      "execute exception")
102DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
103	      "fixpoint divide exception")
104DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
105	      "fixpoint overflow exception")
106DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
107	      "HFP overflow exception")
108DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
109	      "HFP underflow exception")
110DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
111	      "HFP significance exception")
112DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
113	      "HFP divide exception")
114DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
115	      "HFP square root exception")
116DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
117	      "operand exception")
118DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
119	      "privileged operation")
120DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
121	      "special operation exception")
 
 
 
 
122DO_ERROR_INFO(transaction_exception, SIGILL, ILL_ILLOPN,
123	      "transaction constraint exception")
 
124
125static inline void do_fp_trap(struct pt_regs *regs, __u32 fpc)
126{
127	int si_code = 0;
128	/* FPC[2] is Data Exception Code */
129	if ((fpc & 0x00000300) == 0) {
130		/* bits 6 and 7 of DXC are 0 iff IEEE exception */
131		if (fpc & 0x8000) /* invalid fp operation */
132			si_code = FPE_FLTINV;
133		else if (fpc & 0x4000) /* div by 0 */
134			si_code = FPE_FLTDIV;
135		else if (fpc & 0x2000) /* overflow */
136			si_code = FPE_FLTOVF;
137		else if (fpc & 0x1000) /* underflow */
138			si_code = FPE_FLTUND;
139		else if (fpc & 0x0800) /* inexact */
140			si_code = FPE_FLTRES;
141	}
142	do_trap(regs, SIGFPE, si_code, "floating point exception");
143}
144
145static void translation_exception(struct pt_regs *regs)
146{
147	/* May never happen. */
148	panic("Translation exception");
149}
150
151static void illegal_op(struct pt_regs *regs)
152{
 
153        __u8 opcode[6];
154	__u16 __user *location;
155	int is_uprobe_insn = 0;
156	int signal = 0;
157
158	location = get_trap_ip(regs);
159
160	if (user_mode(regs)) {
161		if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
162			return;
163		if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
164			if (current->ptrace)
165				force_sig_fault(SIGTRAP, TRAP_BRKPT, location);
166			else
 
 
 
 
167				signal = SIGILL;
168#ifdef CONFIG_UPROBES
169		} else if (*((__u16 *) opcode) == UPROBE_SWBP_INSN) {
170			is_uprobe_insn = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
171#endif
172		} else
173			signal = SIGILL;
174	}
175	/*
176	 * We got either an illegal op in kernel mode, or user space trapped
177	 * on a uprobes illegal instruction. See if kprobes or uprobes picks
178	 * it up. If not, SIGILL.
179	 */
180	if (is_uprobe_insn || !user_mode(regs)) {
181		if (notify_die(DIE_BPT, "bpt", regs, 0,
182			       3, SIGTRAP) != NOTIFY_STOP)
183			signal = SIGILL;
184	}
 
 
 
 
 
 
 
 
185	if (signal)
186		do_trap(regs, signal, ILL_ILLOPC, "illegal operation");
187}
188NOKPROBE_SYMBOL(illegal_op);
189
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
190DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
191	      "specification exception");
 
192
193static void vector_exception(struct pt_regs *regs)
194{
195	int si_code, vic;
 
196
197	if (!MACHINE_HAS_VX) {
198		do_trap(regs, SIGILL, ILL_ILLOPN, "illegal operation");
199		return;
200	}
201
202	/* get vector interrupt code from fpc */
203	save_fpu_regs();
204	vic = (current->thread.fpu.fpc & 0xf00) >> 8;
205	switch (vic) {
206	case 1: /* invalid vector operation */
207		si_code = FPE_FLTINV;
208		break;
209	case 2: /* division by zero */
210		si_code = FPE_FLTDIV;
211		break;
212	case 3: /* overflow */
213		si_code = FPE_FLTOVF;
214		break;
215	case 4: /* underflow */
216		si_code = FPE_FLTUND;
217		break;
218	case 5:	/* inexact */
219		si_code = FPE_FLTRES;
220		break;
221	default: /* unknown cause */
222		si_code = 0;
223	}
224	do_trap(regs, SIGFPE, si_code, "vector exception");
225}
226
227static void data_exception(struct pt_regs *regs)
228{
229	save_fpu_regs();
230	if (current->thread.fpu.fpc & FPC_DXC_MASK)
231		do_fp_trap(regs, current->thread.fpu.fpc);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
232	else
233		do_trap(regs, SIGILL, ILL_ILLOPN, "data exception");
 
 
 
 
234}
235
236static void space_switch_exception(struct pt_regs *regs)
237{
238	/* Set user psw back to home space mode. */
239	if (user_mode(regs))
240		regs->psw.mask |= PSW_ASC_HOME;
241	/* Send SIGILL. */
242	do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event");
243}
244
245static void monitor_event_exception(struct pt_regs *regs)
246{
247	const struct exception_table_entry *fixup;
248
249	if (user_mode(regs))
250		return;
251
252	switch (report_bug(regs->psw.addr - (regs->int_code >> 16), regs)) {
253	case BUG_TRAP_TYPE_NONE:
254		fixup = s390_search_extables(regs->psw.addr);
255		if (fixup)
256			ex_handle(fixup, regs);
257		break;
258	case BUG_TRAP_TYPE_WARN:
259		break;
260	case BUG_TRAP_TYPE_BUG:
261		die(regs, "monitor event");
262		break;
263	}
264}
265
266void kernel_stack_overflow(struct pt_regs *regs)
267{
268	bust_spinlocks(1);
269	printk("Kernel stack overflow.\n");
270	show_regs(regs);
271	bust_spinlocks(0);
272	panic("Corrupt kernel stack, can't continue.");
273}
274NOKPROBE_SYMBOL(kernel_stack_overflow);
275
276static void __init test_monitor_call(void)
277{
278	int val = 1;
279
280	if (!IS_ENABLED(CONFIG_BUG))
281		return;
282	asm volatile(
283		"	mc	0,0\n"
284		"0:	xgr	%0,%0\n"
285		"1:\n"
286		EX_TABLE(0b,1b)
287		: "+d" (val));
288	if (!val)
289		panic("Monitor call doesn't work!\n");
290}
291
292void __init trap_init(void)
293{
294	sort_extable(__start_dma_ex_table, __stop_dma_ex_table);
295	local_mcck_enable();
296	test_monitor_call();
297}
298
299static void (*pgm_check_table[128])(struct pt_regs *regs);
300
301void noinstr __do_pgm_check(struct pt_regs *regs)
302{
303	unsigned long last_break = S390_lowcore.breaking_event_addr;
304	unsigned int trapnr;
305	irqentry_state_t state;
306
307	regs->int_code = *(u32 *)&S390_lowcore.pgm_ilc;
308	regs->int_parm_long = S390_lowcore.trans_exc_code;
309
310	state = irqentry_enter(regs);
311
312	if (user_mode(regs)) {
313		update_timer_sys();
314		if (last_break < 4096)
315			last_break = 1;
316		current->thread.last_break = last_break;
317		regs->args[0] = last_break;
318	}
319
320	if (S390_lowcore.pgm_code & 0x0200) {
321		/* transaction abort */
322		current->thread.trap_tdb = S390_lowcore.pgm_tdb;
323	}
324
325	if (S390_lowcore.pgm_code & PGM_INT_CODE_PER) {
326		if (user_mode(regs)) {
327			struct per_event *ev = &current->thread.per_event;
328
329			set_thread_flag(TIF_PER_TRAP);
330			ev->address = S390_lowcore.per_address;
331			ev->cause = *(u16 *)&S390_lowcore.per_code;
332			ev->paid = S390_lowcore.per_access_id;
333		} else {
334			/* PER event in kernel is kprobes */
335			__arch_local_irq_ssm(regs->psw.mask & ~PSW_MASK_PER);
336			do_per_trap(regs);
337			goto out;
338		}
339	}
340
341	if (!irqs_disabled_flags(regs->psw.mask))
342		trace_hardirqs_on();
343	__arch_local_irq_ssm(regs->psw.mask & ~PSW_MASK_PER);
344
345	trapnr = regs->int_code & PGM_INT_CODE_MASK;
346	if (trapnr)
347		pgm_check_table[trapnr](regs);
348out:
349	local_irq_disable();
350	irqentry_exit(regs, state);
351}
352
353/*
354 * The program check table contains exactly 128 (0x00-0x7f) entries. Each
355 * line defines the function to be called corresponding to the program check
356 * interruption code.
357 */
358static void (*pgm_check_table[128])(struct pt_regs *regs) = {
359	[0x00]		= default_trap_handler,
360	[0x01]		= illegal_op,
361	[0x02]		= privileged_op,
362	[0x03]		= execute_exception,
363	[0x04]		= do_protection_exception,
364	[0x05]		= addressing_exception,
365	[0x06]		= specification_exception,
366	[0x07]		= data_exception,
367	[0x08]		= overflow_exception,
368	[0x09]		= divide_exception,
369	[0x0a]		= overflow_exception,
370	[0x0b]		= divide_exception,
371	[0x0c]		= hfp_overflow_exception,
372	[0x0d]		= hfp_underflow_exception,
373	[0x0e]		= hfp_significance_exception,
374	[0x0f]		= hfp_divide_exception,
375	[0x10]		= do_dat_exception,
376	[0x11]		= do_dat_exception,
377	[0x12]		= translation_exception,
378	[0x13]		= special_op_exception,
379	[0x14]		= default_trap_handler,
380	[0x15]		= operand_exception,
381	[0x16]		= default_trap_handler,
382	[0x17]		= default_trap_handler,
383	[0x18]		= transaction_exception,
384	[0x19]		= default_trap_handler,
385	[0x1a]		= default_trap_handler,
386	[0x1b]		= vector_exception,
387	[0x1c]		= space_switch_exception,
388	[0x1d]		= hfp_sqrt_exception,
389	[0x1e ... 0x37] = default_trap_handler,
390	[0x38]		= do_dat_exception,
391	[0x39]		= do_dat_exception,
392	[0x3a]		= do_dat_exception,
393	[0x3b]		= do_dat_exception,
394	[0x3c]		= default_trap_handler,
395	[0x3d]		= do_secure_storage_access,
396	[0x3e]		= do_non_secure_storage_access,
397	[0x3f]		= do_secure_storage_violation,
398	[0x40]		= monitor_event_exception,
399	[0x41 ... 0x7f] = default_trap_handler,
400};
401
402#define COND_TRAP(x) asm(			\
403	".weak " __stringify(x) "\n\t"		\
404	".set  " __stringify(x) ","		\
405	__stringify(default_trap_handler))
406
407COND_TRAP(do_secure_storage_access);
408COND_TRAP(do_non_secure_storage_access);
409COND_TRAP(do_secure_storage_violation);