1 // SPDX-License-Identifier: GPL-2.0
3 * Disassemble s390 instructions.
5 * Copyright IBM Corp. 2007
6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
9 #include <linux/sched.h>
10 #include <linux/kernel.h>
11 #include <linux/string.h>
12 #include <linux/errno.h>
13 #include <linux/ptrace.h>
14 #include <linux/timer.h>
16 #include <linux/smp.h>
17 #include <linux/init.h>
18 #include <linux/interrupt.h>
19 #include <linux/delay.h>
20 #include <linux/export.h>
21 #include <linux/kallsyms.h>
22 #include <linux/reboot.h>
23 #include <linux/kprobes.h>
24 #include <linux/kdebug.h>
25 #include <linux/uaccess.h>
26 #include <linux/atomic.h>
29 #include <asm/cpcmd.h>
30 #include <asm/lowcore.h>
31 #include <asm/debug.h>
35 #define OPERAND_GPR 0x1 /* Operand printed as %rx */
36 #define OPERAND_FPR 0x2 /* Operand printed as %fx */
37 #define OPERAND_AR 0x4 /* Operand printed as %ax */
38 #define OPERAND_CR 0x8 /* Operand printed as %cx */
39 #define OPERAND_VR 0x10 /* Operand printed as %vx */
40 #define OPERAND_DISP 0x20 /* Operand printed as displacement */
41 #define OPERAND_BASE 0x40 /* Operand printed as base register */
42 #define OPERAND_INDEX 0x80 /* Operand printed as index register */
43 #define OPERAND_PCREL 0x100 /* Operand printed as pc-relative symbol */
44 #define OPERAND_SIGNED 0x200 /* Operand printed as signed value */
45 #define OPERAND_LENGTH 0x400 /* Operand printed as length (+1) */
48 unsigned char bits; /* The number of bits in the operand. */
49 unsigned char shift; /* The number of bits to shift. */
50 unsigned short flags; /* One bit syntax flags. */
65 struct s390_opcode_offset {
69 unsigned short offset;
75 A_8, /* Access reg. starting at position 8 */
76 A_12, /* Access reg. starting at position 12 */
77 A_24, /* Access reg. starting at position 24 */
78 A_28, /* Access reg. starting at position 28 */
79 B_16, /* Base register starting at position 16 */
80 B_32, /* Base register starting at position 32 */
81 C_8, /* Control reg. starting at position 8 */
82 C_12, /* Control reg. starting at position 12 */
83 D20_20, /* 20 bit displacement starting at 20 */
84 D_20, /* Displacement starting at position 20 */
85 D_36, /* Displacement starting at position 36 */
86 F_8, /* FPR starting at position 8 */
87 F_12, /* FPR starting at position 12 */
88 F_16, /* FPR starting at position 16 */
89 F_24, /* FPR starting at position 24 */
90 F_28, /* FPR starting at position 28 */
91 F_32, /* FPR starting at position 32 */
92 I8_8, /* 8 bit signed value starting at 8 */
93 I8_32, /* 8 bit signed value starting at 32 */
94 I16_16, /* 16 bit signed value starting at 16 */
95 I16_32, /* 16 bit signed value starting at 32 */
96 I32_16, /* 32 bit signed value starting at 16 */
97 J12_12, /* 12 bit PC relative offset at 12 */
98 J16_16, /* 16 bit PC relative offset at 16 */
99 J16_32, /* 16 bit PC relative offset at 32 */
100 J24_24, /* 24 bit PC relative offset at 24 */
101 J32_16, /* 32 bit PC relative offset at 16 */
102 L4_8, /* 4 bit length starting at position 8 */
103 L4_12, /* 4 bit length starting at position 12 */
104 L8_8, /* 8 bit length starting at position 8 */
105 R_8, /* GPR starting at position 8 */
106 R_12, /* GPR starting at position 12 */
107 R_16, /* GPR starting at position 16 */
108 R_24, /* GPR starting at position 24 */
109 R_28, /* GPR starting at position 28 */
110 U4_8, /* 4 bit unsigned value starting at 8 */
111 U4_12, /* 4 bit unsigned value starting at 12 */
112 U4_16, /* 4 bit unsigned value starting at 16 */
113 U4_20, /* 4 bit unsigned value starting at 20 */
114 U4_24, /* 4 bit unsigned value starting at 24 */
115 U4_28, /* 4 bit unsigned value starting at 28 */
116 U4_32, /* 4 bit unsigned value starting at 32 */
117 U4_36, /* 4 bit unsigned value starting at 36 */
118 U8_8, /* 8 bit unsigned value starting at 8 */
119 U8_16, /* 8 bit unsigned value starting at 16 */
120 U8_24, /* 8 bit unsigned value starting at 24 */
121 U8_28, /* 8 bit unsigned value starting at 28 */
122 U8_32, /* 8 bit unsigned value starting at 32 */
123 U12_16, /* 12 bit unsigned value starting at 16 */
124 U16_16, /* 16 bit unsigned value starting at 16 */
125 U16_32, /* 16 bit unsigned value starting at 32 */
126 U32_16, /* 32 bit unsigned value starting at 16 */
127 VX_12, /* Vector index register starting at position 12 */
128 V_8, /* Vector reg. starting at position 8 */
129 V_12, /* Vector reg. starting at position 12 */
130 V_16, /* Vector reg. starting at position 16 */
131 V_32, /* Vector reg. starting at position 32 */
132 X_12, /* Index register starting at position 12 */
135 static const struct s390_operand operands[] = {
136 [UNUSED] = { 0, 0, 0 },
137 [A_8] = { 4, 8, OPERAND_AR },
138 [A_12] = { 4, 12, OPERAND_AR },
139 [A_24] = { 4, 24, OPERAND_AR },
140 [A_28] = { 4, 28, OPERAND_AR },
141 [B_16] = { 4, 16, OPERAND_BASE | OPERAND_GPR },
142 [B_32] = { 4, 32, OPERAND_BASE | OPERAND_GPR },
143 [C_8] = { 4, 8, OPERAND_CR },
144 [C_12] = { 4, 12, OPERAND_CR },
145 [D20_20] = { 20, 20, OPERAND_DISP | OPERAND_SIGNED },
146 [D_20] = { 12, 20, OPERAND_DISP },
147 [D_36] = { 12, 36, OPERAND_DISP },
148 [F_8] = { 4, 8, OPERAND_FPR },
149 [F_12] = { 4, 12, OPERAND_FPR },
150 [F_16] = { 4, 16, OPERAND_FPR },
151 [F_24] = { 4, 24, OPERAND_FPR },
152 [F_28] = { 4, 28, OPERAND_FPR },
153 [F_32] = { 4, 32, OPERAND_FPR },
154 [I8_8] = { 8, 8, OPERAND_SIGNED },
155 [I8_32] = { 8, 32, OPERAND_SIGNED },
156 [I16_16] = { 16, 16, OPERAND_SIGNED },
157 [I16_32] = { 16, 32, OPERAND_SIGNED },
158 [I32_16] = { 32, 16, OPERAND_SIGNED },
159 [J12_12] = { 12, 12, OPERAND_PCREL },
160 [J16_16] = { 16, 16, OPERAND_PCREL },
161 [J16_32] = { 16, 32, OPERAND_PCREL },
162 [J24_24] = { 24, 24, OPERAND_PCREL },
163 [J32_16] = { 32, 16, OPERAND_PCREL },
164 [L4_8] = { 4, 8, OPERAND_LENGTH },
165 [L4_12] = { 4, 12, OPERAND_LENGTH },
166 [L8_8] = { 8, 8, OPERAND_LENGTH },
167 [R_8] = { 4, 8, OPERAND_GPR },
168 [R_12] = { 4, 12, OPERAND_GPR },
169 [R_16] = { 4, 16, OPERAND_GPR },
170 [R_24] = { 4, 24, OPERAND_GPR },
171 [R_28] = { 4, 28, OPERAND_GPR },
172 [U4_8] = { 4, 8, 0 },
173 [U4_12] = { 4, 12, 0 },
174 [U4_16] = { 4, 16, 0 },
175 [U4_20] = { 4, 20, 0 },
176 [U4_24] = { 4, 24, 0 },
177 [U4_28] = { 4, 28, 0 },
178 [U4_32] = { 4, 32, 0 },
179 [U4_36] = { 4, 36, 0 },
180 [U8_8] = { 8, 8, 0 },
181 [U8_16] = { 8, 16, 0 },
182 [U8_24] = { 8, 24, 0 },
183 [U8_28] = { 8, 28, 0 },
184 [U8_32] = { 8, 32, 0 },
185 [U12_16] = { 12, 16, 0 },
186 [U16_16] = { 16, 16, 0 },
187 [U16_32] = { 16, 32, 0 },
188 [U32_16] = { 32, 16, 0 },
189 [VX_12] = { 4, 12, OPERAND_INDEX | OPERAND_VR },
190 [V_8] = { 4, 8, OPERAND_VR },
191 [V_12] = { 4, 12, OPERAND_VR },
192 [V_16] = { 4, 16, OPERAND_VR },
193 [V_32] = { 4, 32, OPERAND_VR },
194 [X_12] = { 4, 12, OPERAND_INDEX | OPERAND_GPR },
197 static const unsigned char formats[][6] = {
198 [INSTR_E] = { 0, 0, 0, 0, 0, 0 },
199 [INSTR_IE_UU] = { U4_24, U4_28, 0, 0, 0, 0 },
200 [INSTR_MII_UPP] = { U4_8, J12_12, J24_24 },
201 [INSTR_RIE_R0IU] = { R_8, I16_16, U4_32, 0, 0, 0 },
202 [INSTR_RIE_R0UU] = { R_8, U16_16, U4_32, 0, 0, 0 },
203 [INSTR_RIE_RRI0] = { R_8, R_12, I16_16, 0, 0, 0 },
204 [INSTR_RIE_RRP] = { R_8, R_12, J16_16, 0, 0, 0 },
205 [INSTR_RIE_RRPU] = { R_8, R_12, U4_32, J16_16, 0, 0 },
206 [INSTR_RIE_RRUUU] = { R_8, R_12, U8_16, U8_24, U8_32, 0 },
207 [INSTR_RIE_RUI0] = { R_8, I16_16, U4_12, 0, 0, 0 },
208 [INSTR_RIE_RUPI] = { R_8, I8_32, U4_12, J16_16, 0, 0 },
209 [INSTR_RIE_RUPU] = { R_8, U8_32, U4_12, J16_16, 0, 0 },
210 [INSTR_RIL_RI] = { R_8, I32_16, 0, 0, 0, 0 },
211 [INSTR_RIL_RP] = { R_8, J32_16, 0, 0, 0, 0 },
212 [INSTR_RIL_RU] = { R_8, U32_16, 0, 0, 0, 0 },
213 [INSTR_RIL_UP] = { U4_8, J32_16, 0, 0, 0, 0 },
214 [INSTR_RIS_RURDI] = { R_8, I8_32, U4_12, D_20, B_16, 0 },
215 [INSTR_RIS_RURDU] = { R_8, U8_32, U4_12, D_20, B_16, 0 },
216 [INSTR_RI_RI] = { R_8, I16_16, 0, 0, 0, 0 },
217 [INSTR_RI_RP] = { R_8, J16_16, 0, 0, 0, 0 },
218 [INSTR_RI_RU] = { R_8, U16_16, 0, 0, 0, 0 },
219 [INSTR_RI_UP] = { U4_8, J16_16, 0, 0, 0, 0 },
220 [INSTR_RRE_00] = { 0, 0, 0, 0, 0, 0 },
221 [INSTR_RRE_AA] = { A_24, A_28, 0, 0, 0, 0 },
222 [INSTR_RRE_AR] = { A_24, R_28, 0, 0, 0, 0 },
223 [INSTR_RRE_F0] = { F_24, 0, 0, 0, 0, 0 },
224 [INSTR_RRE_FF] = { F_24, F_28, 0, 0, 0, 0 },
225 [INSTR_RRE_FR] = { F_24, R_28, 0, 0, 0, 0 },
226 [INSTR_RRE_R0] = { R_24, 0, 0, 0, 0, 0 },
227 [INSTR_RRE_RA] = { R_24, A_28, 0, 0, 0, 0 },
228 [INSTR_RRE_RF] = { R_24, F_28, 0, 0, 0, 0 },
229 [INSTR_RRE_RR] = { R_24, R_28, 0, 0, 0, 0 },
230 [INSTR_RRF_0UFF] = { F_24, F_28, U4_20, 0, 0, 0 },
231 [INSTR_RRF_0URF] = { R_24, F_28, U4_20, 0, 0, 0 },
232 [INSTR_RRF_F0FF] = { F_16, F_24, F_28, 0, 0, 0 },
233 [INSTR_RRF_F0FF2] = { F_24, F_16, F_28, 0, 0, 0 },
234 [INSTR_RRF_F0FR] = { F_24, F_16, R_28, 0, 0, 0 },
235 [INSTR_RRF_FFRU] = { F_24, F_16, R_28, U4_20, 0, 0 },
236 [INSTR_RRF_FUFF] = { F_24, F_16, F_28, U4_20, 0, 0 },
237 [INSTR_RRF_FUFF2] = { F_24, F_28, F_16, U4_20, 0, 0 },
238 [INSTR_RRF_R0RR] = { R_24, R_16, R_28, 0, 0, 0 },
239 [INSTR_RRF_R0RR2] = { R_24, R_28, R_16, 0, 0, 0 },
240 [INSTR_RRF_RURR] = { R_24, R_28, R_16, U4_20, 0, 0 },
241 [INSTR_RRF_RURR2] = { R_24, R_16, R_28, U4_20, 0, 0 },
242 [INSTR_RRF_U0FF] = { F_24, U4_16, F_28, 0, 0, 0 },
243 [INSTR_RRF_U0RF] = { R_24, U4_16, F_28, 0, 0, 0 },
244 [INSTR_RRF_U0RR] = { R_24, R_28, U4_16, 0, 0, 0 },
245 [INSTR_RRF_URR] = { R_24, R_28, U8_16, 0, 0, 0 },
246 [INSTR_RRF_UUFF] = { F_24, U4_16, F_28, U4_20, 0, 0 },
247 [INSTR_RRF_UUFR] = { F_24, U4_16, R_28, U4_20, 0, 0 },
248 [INSTR_RRF_UURF] = { R_24, U4_16, F_28, U4_20, 0, 0 },
249 [INSTR_RRS_RRRDU] = { R_8, R_12, U4_32, D_20, B_16 },
250 [INSTR_RR_FF] = { F_8, F_12, 0, 0, 0, 0 },
251 [INSTR_RR_R0] = { R_8, 0, 0, 0, 0, 0 },
252 [INSTR_RR_RR] = { R_8, R_12, 0, 0, 0, 0 },
253 [INSTR_RR_U0] = { U8_8, 0, 0, 0, 0, 0 },
254 [INSTR_RR_UR] = { U4_8, R_12, 0, 0, 0, 0 },
255 [INSTR_RSI_RRP] = { R_8, R_12, J16_16, 0, 0, 0 },
256 [INSTR_RSL_LRDFU] = { F_32, D_20, L8_8, B_16, U4_36, 0 },
257 [INSTR_RSL_R0RD] = { D_20, L4_8, B_16, 0, 0, 0 },
258 [INSTR_RSY_AARD] = { A_8, A_12, D20_20, B_16, 0, 0 },
259 [INSTR_RSY_CCRD] = { C_8, C_12, D20_20, B_16, 0, 0 },
260 [INSTR_RSY_RDRU] = { R_8, D20_20, B_16, U4_12, 0, 0 },
261 [INSTR_RSY_RRRD] = { R_8, R_12, D20_20, B_16, 0, 0 },
262 [INSTR_RSY_RURD] = { R_8, U4_12, D20_20, B_16, 0, 0 },
263 [INSTR_RSY_RURD2] = { R_8, D20_20, B_16, U4_12, 0, 0 },
264 [INSTR_RS_AARD] = { A_8, A_12, D_20, B_16, 0, 0 },
265 [INSTR_RS_CCRD] = { C_8, C_12, D_20, B_16, 0, 0 },
266 [INSTR_RS_R0RD] = { R_8, D_20, B_16, 0, 0, 0 },
267 [INSTR_RS_RRRD] = { R_8, R_12, D_20, B_16, 0, 0 },
268 [INSTR_RS_RURD] = { R_8, U4_12, D_20, B_16, 0, 0 },
269 [INSTR_RXE_FRRD] = { F_8, D_20, X_12, B_16, 0, 0 },
270 [INSTR_RXE_RRRDU] = { R_8, D_20, X_12, B_16, U4_32, 0 },
271 [INSTR_RXF_FRRDF] = { F_32, F_8, D_20, X_12, B_16, 0 },
272 [INSTR_RXY_FRRD] = { F_8, D20_20, X_12, B_16, 0, 0 },
273 [INSTR_RXY_RRRD] = { R_8, D20_20, X_12, B_16, 0, 0 },
274 [INSTR_RXY_URRD] = { U4_8, D20_20, X_12, B_16, 0, 0 },
275 [INSTR_RX_FRRD] = { F_8, D_20, X_12, B_16, 0, 0 },
276 [INSTR_RX_RRRD] = { R_8, D_20, X_12, B_16, 0, 0 },
277 [INSTR_RX_URRD] = { U4_8, D_20, X_12, B_16, 0, 0 },
278 [INSTR_SIL_RDI] = { D_20, B_16, I16_32, 0, 0, 0 },
279 [INSTR_SIL_RDU] = { D_20, B_16, U16_32, 0, 0, 0 },
280 [INSTR_SIY_IRD] = { D20_20, B_16, I8_8, 0, 0, 0 },
281 [INSTR_SIY_URD] = { D20_20, B_16, U8_8, 0, 0, 0 },
282 [INSTR_SI_RD] = { D_20, B_16, 0, 0, 0, 0 },
283 [INSTR_SI_URD] = { D_20, B_16, U8_8, 0, 0, 0 },
284 [INSTR_SMI_U0RDP] = { U4_8, J16_32, D_20, B_16, 0, 0 },
285 [INSTR_SSE_RDRD] = { D_20, B_16, D_36, B_32, 0, 0 },
286 [INSTR_SSF_RRDRD] = { D_20, B_16, D_36, B_32, R_8, 0 },
287 [INSTR_SSF_RRDRD2] = { R_8, D_20, B_16, D_36, B_32, 0 },
288 [INSTR_SS_L0RDRD] = { D_20, L8_8, B_16, D_36, B_32, 0 },
289 [INSTR_SS_L2RDRD] = { D_20, B_16, D_36, L8_8, B_32, 0 },
290 [INSTR_SS_LIRDRD] = { D_20, L4_8, B_16, D_36, B_32, U4_12 },
291 [INSTR_SS_LLRDRD] = { D_20, L4_8, B_16, D_36, L4_12, B_32 },
292 [INSTR_SS_RRRDRD] = { D_20, R_8, B_16, D_36, B_32, R_12 },
293 [INSTR_SS_RRRDRD2] = { R_8, D_20, B_16, R_12, D_36, B_32 },
294 [INSTR_SS_RRRDRD3] = { R_8, R_12, D_20, B_16, D_36, B_32 },
295 [INSTR_S_00] = { 0, 0, 0, 0, 0, 0 },
296 [INSTR_S_RD] = { D_20, B_16, 0, 0, 0, 0 },
297 [INSTR_VRI_V0IU] = { V_8, I16_16, U4_32, 0, 0, 0 },
298 [INSTR_VRI_V0U] = { V_8, U16_16, 0, 0, 0, 0 },
299 [INSTR_VRI_V0UU2] = { V_8, U16_16, U4_32, 0, 0, 0 },
300 [INSTR_VRI_V0UUU] = { V_8, U8_16, U8_24, U4_32, 0, 0 },
301 [INSTR_VRI_VR0UU] = { V_8, R_12, U8_28, U4_24, 0, 0 },
302 [INSTR_VRI_VVUU] = { V_8, V_12, U16_16, U4_32, 0, 0 },
303 [INSTR_VRI_VVUUU] = { V_8, V_12, U12_16, U4_32, U4_28, 0 },
304 [INSTR_VRI_VVUUU2] = { V_8, V_12, U8_28, U8_16, U4_24, 0 },
305 [INSTR_VRI_VVV0U] = { V_8, V_12, V_16, U8_24, 0, 0 },
306 [INSTR_VRI_VVV0UU] = { V_8, V_12, V_16, U8_24, U4_32, 0 },
307 [INSTR_VRI_VVV0UU2] = { V_8, V_12, V_16, U8_28, U4_24, 0 },
308 [INSTR_VRR_0V] = { V_12, 0, 0, 0, 0, 0 },
309 [INSTR_VRR_0VV0U] = { V_12, V_16, U4_24, 0, 0, 0 },
310 [INSTR_VRR_RV0UU] = { R_8, V_12, U4_24, U4_28, 0, 0 },
311 [INSTR_VRR_VRR] = { V_8, R_12, R_16, 0, 0, 0 },
312 [INSTR_VRR_VV] = { V_8, V_12, 0, 0, 0, 0 },
313 [INSTR_VRR_VV0U] = { V_8, V_12, U4_32, 0, 0, 0 },
314 [INSTR_VRR_VV0U0U] = { V_8, V_12, U4_32, U4_24, 0, 0 },
315 [INSTR_VRR_VV0UU2] = { V_8, V_12, U4_32, U4_28, 0, 0 },
316 [INSTR_VRR_VV0UUU] = { V_8, V_12, U4_32, U4_28, U4_24, 0 },
317 [INSTR_VRR_VVV] = { V_8, V_12, V_16, 0, 0, 0 },
318 [INSTR_VRR_VVV0U] = { V_8, V_12, V_16, U4_32, 0, 0 },
319 [INSTR_VRR_VVV0U0U] = { V_8, V_12, V_16, U4_32, U4_24, 0 },
320 [INSTR_VRR_VVV0UU] = { V_8, V_12, V_16, U4_32, U4_28, 0 },
321 [INSTR_VRR_VVV0UUU] = { V_8, V_12, V_16, U4_32, U4_28, U4_24 },
322 [INSTR_VRR_VVV0V] = { V_8, V_12, V_16, V_32, 0, 0 },
323 [INSTR_VRR_VVVU0UV] = { V_8, V_12, V_16, V_32, U4_28, U4_20 },
324 [INSTR_VRR_VVVU0V] = { V_8, V_12, V_16, V_32, U4_20, 0 },
325 [INSTR_VRR_VVVUU0V] = { V_8, V_12, V_16, V_32, U4_20, U4_24 },
326 [INSTR_VRS_RRDV] = { V_32, R_12, D_20, B_16, 0, 0 },
327 [INSTR_VRS_RVRDU] = { R_8, V_12, D_20, B_16, U4_32, 0 },
328 [INSTR_VRS_VRRD] = { V_8, R_12, D_20, B_16, 0, 0 },
329 [INSTR_VRS_VRRDU] = { V_8, R_12, D_20, B_16, U4_32, 0 },
330 [INSTR_VRS_VVRDU] = { V_8, V_12, D_20, B_16, U4_32, 0 },
331 [INSTR_VRV_VVXRDU] = { V_8, D_20, VX_12, B_16, U4_32, 0 },
332 [INSTR_VRX_VRRDU] = { V_8, D_20, X_12, B_16, U4_32, 0 },
333 [INSTR_VRX_VV] = { V_8, V_12, 0, 0, 0, 0 },
334 [INSTR_VSI_URDV] = { V_32, D_20, B_16, U8_8, 0, 0 },
337 static char long_insn_name[][7] = LONG_INSN_INITIALIZER;
338 static struct s390_insn opcode[] = OPCODE_TABLE_INITIALIZER;
339 static struct s390_opcode_offset opcode_offset[] = OPCODE_OFFSET_INITIALIZER;
341 /* Extracts an operand value from an instruction. */
342 static unsigned int extract_operand(unsigned char *code,
343 const struct s390_operand *operand)
349 /* Extract fragments of the operand byte for byte. */
350 cp = code + operand->shift / 8;
351 bits = (operand->shift & 7) + operand->bits;
355 val |= (unsigned int) *cp++;
359 val &= ((1U << (operand->bits - 1)) << 1) - 1;
361 /* Check for special long displacement case. */
362 if (operand->bits == 20 && operand->shift == 20)
363 val = (val & 0xff) << 12 | (val & 0xfff00) >> 8;
365 /* Check for register extensions bits for vector registers. */
366 if (operand->flags & OPERAND_VR) {
367 if (operand->shift == 8)
368 val |= (code[4] & 8) << 1;
369 else if (operand->shift == 12)
370 val |= (code[4] & 4) << 2;
371 else if (operand->shift == 16)
372 val |= (code[4] & 2) << 3;
373 else if (operand->shift == 32)
374 val |= (code[4] & 1) << 4;
377 /* Sign extend value if the operand is signed or pc relative. */
378 if ((operand->flags & (OPERAND_SIGNED | OPERAND_PCREL)) &&
379 (val & (1U << (operand->bits - 1))))
380 val |= (-1U << (operand->bits - 1)) << 1;
382 /* Double value if the operand is pc relative. */
383 if (operand->flags & OPERAND_PCREL)
386 /* Length x in an instructions has real length x + 1. */
387 if (operand->flags & OPERAND_LENGTH)
392 struct s390_insn *find_insn(unsigned char *code)
394 struct s390_opcode_offset *entry;
395 struct s390_insn *insn;
396 unsigned char opfrag;
399 /* Search the opcode offset table to find an entry which
400 * matches the beginning of the opcode. If there is no match
401 * the last entry will be used, which is the default entry for
402 * unknown instructions as well as 1-byte opcode instructions.
404 for (i = 0; i < ARRAY_SIZE(opcode_offset); i++) {
405 entry = &opcode_offset[i];
406 if (entry->opcode == code[0])
410 opfrag = *(code + entry->byte) & entry->mask;
412 insn = &opcode[entry->offset];
413 for (i = 0; i < entry->count; i++) {
414 if (insn->opfrag == opfrag)
421 static int print_insn(char *buffer, unsigned char *code, unsigned long addr)
423 struct s390_insn *insn;
424 const unsigned char *ops;
425 const struct s390_operand *operand;
432 insn = find_insn(code);
435 ptr += sprintf(ptr, "%.7s\t",
436 long_insn_name[insn->offset]);
438 ptr += sprintf(ptr, "%.5s\t", insn->name);
439 /* Extract the operands. */
441 for (ops = formats[insn->format], i = 0;
442 *ops != 0 && i < 6; ops++, i++) {
443 operand = operands + *ops;
444 value = extract_operand(code, operand);
445 if ((operand->flags & OPERAND_INDEX) && value == 0)
447 if ((operand->flags & OPERAND_BASE) &&
448 value == 0 && separator == '(') {
453 ptr += sprintf(ptr, "%c", separator);
454 if (operand->flags & OPERAND_GPR)
455 ptr += sprintf(ptr, "%%r%i", value);
456 else if (operand->flags & OPERAND_FPR)
457 ptr += sprintf(ptr, "%%f%i", value);
458 else if (operand->flags & OPERAND_AR)
459 ptr += sprintf(ptr, "%%a%i", value);
460 else if (operand->flags & OPERAND_CR)
461 ptr += sprintf(ptr, "%%c%i", value);
462 else if (operand->flags & OPERAND_VR)
463 ptr += sprintf(ptr, "%%v%i", value);
464 else if (operand->flags & OPERAND_PCREL) {
465 void *pcrel = (void *)((int)value + addr);
467 ptr += sprintf(ptr, "%px", pcrel);
468 } else if (operand->flags & OPERAND_SIGNED)
469 ptr += sprintf(ptr, "%i", value);
471 ptr += sprintf(ptr, "%u", value);
472 if (operand->flags & OPERAND_DISP)
474 else if (operand->flags & OPERAND_BASE) {
475 ptr += sprintf(ptr, ")");
481 ptr += sprintf(ptr, "unknown");
482 return (int) (ptr - buffer);
485 static int copy_from_regs(struct pt_regs *regs, void *dst, void *src, int len)
487 if (user_mode(regs)) {
488 if (copy_from_user(dst, (char __user *)src, len))
491 if (copy_from_kernel_nofault(dst, src, len))
497 void show_code(struct pt_regs *regs)
499 char *mode = user_mode(regs) ? "User" : "Krnl";
500 unsigned char code[64];
501 char buffer[128], *ptr;
503 int start, end, opsize, hops, i;
505 /* Get a snapshot of the 64 bytes surrounding the fault address. */
506 for (start = 32; start && regs->psw.addr >= 34 - start; start -= 2) {
507 addr = regs->psw.addr - 34 + start;
508 if (copy_from_regs(regs, code + start - 2, (void *)addr, 2))
511 for (end = 32; end < 64; end += 2) {
512 addr = regs->psw.addr + end - 32;
513 if (copy_from_regs(regs, code + end, (void *)addr, 2))
516 /* Code snapshot useable ? */
517 if ((regs->psw.addr & 1) || start >= end) {
518 printk("%s Code: Bad PSW.\n", mode);
521 /* Find a starting point for the disassembly. */
523 for (i = 0, hops = 0; start + i < 32 && hops < 3; hops++) {
524 if (!find_insn(code + start + i))
526 i += insn_length(code[start + i]);
529 /* Looks good, sequence ends at PSW. */
533 /* Decode the instructions. */
535 ptr += sprintf(ptr, "%s Code:", mode);
537 while (start < end && hops < 8) {
538 opsize = insn_length(code[start]);
539 if (start + opsize == 32)
541 else if (start == 32)
545 addr = regs->psw.addr + start - 32;
546 ptr += sprintf(ptr, "%px: ", (void *)addr);
547 if (start + opsize >= end)
549 for (i = 0; i < opsize; i++)
550 ptr += sprintf(ptr, "%02x", code[start + i]);
554 ptr += print_insn(ptr, code + start, addr);
556 pr_cont("%s", buffer);
558 ptr += sprintf(ptr, "\n ");
564 void print_fn_code(unsigned char *code, unsigned long len)
566 char buffer[128], *ptr;
571 opsize = insn_length(*code);
574 ptr += sprintf(ptr, "%px: ", code);
575 for (i = 0; i < opsize; i++)
576 ptr += sprintf(ptr, "%02x", code[i]);
580 ptr += print_insn(ptr, code, (unsigned long) code);
583 printk("%s", buffer);