cpu_x86_64.c revision 1.2.28.1
1 /* $NetBSD: cpu_x86_64.c,v 1.2.28.1 2019/01/30 13:32:58 martin Exp $ */ 2 3 /*- 4 * Copyright (c) 2011 Reinoud Zandijk <reinoud (at) netbsd.org> 5 * Copyright (c) 2007 Jared D. McNeill <jmcneill (at) invisible.ca> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 /* 31 * Note that this machdep.c uses the `dummy' mcontext_t defined for usermode. 32 * This is basicly a blob of PAGE_SIZE big. We might want to switch over to 33 * non-generic mcontext_t's one day, but will this break non-NetBSD hosts? 34 */ 35 36 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: cpu_x86_64.c,v 1.2.28.1 2019/01/30 13:32:58 martin Exp $"); 39 40 #include <sys/types.h> 41 #include <sys/systm.h> 42 #include <sys/param.h> 43 #include <sys/time.h> 44 #include <sys/exec.h> 45 #include <sys/buf.h> 46 #include <sys/boot_flag.h> 47 #include <sys/ucontext.h> 48 #include <sys/utsname.h> 49 #include <machine/pcb.h> 50 #include <machine/psl.h> 51 52 #include <uvm/uvm_extern.h> 53 #include <uvm/uvm_page.h> 54 55 #include <dev/mm.h> 56 #include <machine/machdep.h> 57 #include <machine/thunk.h> 58 59 60 #if 0 61 static void dump_regs(register_t *reg);; 62 63 static void 64 dump_regs(register_t *reg) 65 { 66 int i; 67 68 /* register dump before call */ 69 const char *name[] = {"RDI", "RSI", "RDX", "RCX", "R8", "R9", "R10", 70 "R11", "R12", "R13", "R14", "R15", "RBP", "RAX", 71 "GS", "FS", "ES", "DS", "TRAPNO", "ERR", "RIP", "CS", 72 "RFLAGS", "RSP", "SS"}; 73 74 for (i =0; i < 26; i++) 75 printf("reg[%02d] (%6s) = %"PRIx32"\n", 76 i, name[i], (uint32_t) reg[i]); 77 } 78 #endif 79 80 81 /* from sys/arch/amd64/include/frame.h : KEEP IN SYNC */ 82 83 /* 84 * Signal frame 85 */ 86 struct sigframe_siginfo { 87 uint64_t sf_ra; /* return address for handler */ 88 siginfo_t sf_si; /* actual saved siginfo */ 89 ucontext_t sf_uc; /* actual saved ucontext */ 90 }; 91 92 93 /* should be the same as i386 */ 94 /* 95 * mcontext extensions to handle signal delivery. 96 */ 97 #define _UC_SETSTACK 0x00010000 98 #define _UC_CLRSTACK 0x00020000 99 #define _UC_VM 0x00040000 100 #define _UC_TLSBASE 0x00080000 101 102 103 void 104 sendsig_siginfo(const ksiginfo_t *ksi, const sigset_t *mask) 105 { 106 struct lwp *l = curlwp; 107 struct proc *p = l->l_proc; 108 struct pcb *pcb = lwp_getpcb(l); 109 struct sigacts *ps = p->p_sigacts; 110 struct sigframe_siginfo *fp, frame; 111 int sig = ksi->ksi_signo; 112 sig_t catcher = SIGACTION(p, sig).sa_handler; 113 ucontext_t *ucp; 114 register_t *reg; 115 int onstack, error; 116 char *sp; 117 118 KASSERT(mutex_owned(p->p_lock)); 119 120 ucp = &pcb->pcb_userret_ucp; 121 reg = (register_t *) &ucp->uc_mcontext; 122 #if 0 123 thunk_printf("%s: ", __func__); 124 thunk_printf("flags %d, ", (int) ksi->ksi_flags); 125 thunk_printf("to lwp %d, signo %d, code %d, errno %d\n", 126 (int) ksi->ksi_lid, 127 ksi->ksi_signo, 128 ksi->ksi_code, 129 ksi->ksi_errno); 130 #endif 131 132 /* do we need to jump onto the signal stack? */ 133 onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 134 && (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; 135 136 sp = ((char *) reg[24] - 128);/* why -128?*//* RSP */ 137 if (onstack) 138 sp = (char *) l->l_sigstk.ss_sp + l->l_sigstk.ss_size; 139 140 sp -= sizeof(struct sigframe_siginfo); 141 /* 142 * Round down the stackpointer to a multiple of 16 for 143 * fxsave and the ABI 144 */ 145 fp = (struct sigframe_siginfo *) (((unsigned long)sp & ~15) - 8); 146 147 /* set up stack frame */ 148 memset(&frame, 0, sizeof(frame)); 149 frame.sf_ra = (uint64_t) ps->sa_sigdesc[sig].sd_tramp; 150 frame.sf_si._info = ksi->ksi_info; 151 152 /* copy our userret context into sf_uc */ 153 memcpy(&frame.sf_uc, ucp, sizeof(ucontext_t)); 154 frame.sf_uc.uc_sigmask = *mask; 155 frame.sf_uc.uc_link = l->l_ctxlink; 156 frame.sf_uc.uc_flags |= (l->l_sigstk.ss_flags & SS_ONSTACK) 157 ? _UC_SETSTACK : _UC_CLRSTACK; 158 memset(&frame.sf_uc.uc_stack, 0, sizeof(frame.sf_uc.uc_stack)); 159 sendsig_reset(l, sig); 160 161 /* copyout our frame to the stackframe */ 162 mutex_exit(p->p_lock); 163 error = copyout(&frame, fp, sizeof(frame)); 164 mutex_enter(p->p_lock); 165 166 if (error != 0) { 167 /* 168 * Process has trashed its stack; give it an illegal 169 * instruction to halt it in its tracks. 170 */ 171 sigexit(l, SIGILL); 172 /* NOTREACHED */ 173 } 174 175 /* set catcher and the new stack pointer */ 176 reg[24] = (register_t) fp; /* RSP */ 177 reg[21] = (register_t) catcher; /* RIP */ 178 179 reg[ 0] = sig; /* RDI */ 180 reg[ 1] = (uint64_t) &fp->sf_si; /* RSI */ 181 reg[ 2] = (uint64_t) &fp->sf_uc; /* RDX */ 182 reg[11] = reg[ 2]; /* R15 = RDX */ 183 184 /* Remember that we're now on the signal stack. */ 185 if (onstack) 186 l->l_sigstk.ss_flags |= SS_ONSTACK; 187 } 188 189 void 190 setregs(struct lwp *l, struct exec_package *pack, vaddr_t stack) 191 { 192 struct pcb *pcb = lwp_getpcb(l); 193 ucontext_t *ucp; 194 register_t *reg; 195 int i; 196 197 /* set up the user context */ 198 ucp = &pcb->pcb_userret_ucp; 199 reg = (register_t *) &ucp->uc_mcontext; 200 for (i = 0; i < 15; i++) 201 reg[i] = 0; 202 203 reg[13] = l->l_proc->p_psstrp; /* RBX */ 204 reg[21] = pack->ep_entry; /* RIP */ 205 reg[24] = (register_t) stack; /* RSP */ 206 207 /* use given stack */ 208 ucp->uc_stack.ss_sp = (void *) stack; 209 ucp->uc_stack.ss_size = pack->ep_ssize; 210 211 //dump_regs(reg); 212 } 213 214 void 215 md_syscall_get_syscallnumber(ucontext_t *ucp, uint32_t *code) 216 { 217 register_t *reg = (register_t *) &ucp->uc_mcontext; 218 *code = reg[14]; /* RAX */ 219 } 220 221 int 222 md_syscall_getargs(lwp_t *l, ucontext_t *ucp, int nargs, int argsize, 223 register_t *args) 224 { 225 register_t *reg = (register_t *) &ucp->uc_mcontext; 226 register_t *sp = (register_t *) reg[24];/* RSP */ 227 int ret; 228 229 //dump_regs(reg); 230 231 /* 232 * 1st 6 syscall args are passed in 233 * rdi, rsi, rdx, r10, r8 and r9 234 */ 235 args[0] = reg[ 0]; /* RDI */ 236 args[1] = reg[ 1]; /* RSI */ 237 args[2] = reg[ 2]; /* RDX */ 238 args[3] = reg[ 6]; /* R10 (RCX got clobbered) */ 239 args[4] = reg[ 4]; /* R8 */ 240 args[5] = reg[ 5]; /* R9 */ 241 242 ret = 0; 243 if (argsize > 6 * 8) { 244 ret = copyin(sp + 1, 245 args + 6, argsize - 6 * 8); 246 } 247 248 return ret; 249 } 250 251 void 252 md_syscall_set_returnargs(lwp_t *l, ucontext_t *ucp, 253 int error, register_t *rval) 254 { 255 register_t *reg = (register_t *) &ucp->uc_mcontext; 256 257 reg[23] &= ~PSL_C; /* RFLAGS */ 258 if (error > 0) { 259 rval[0] = error; 260 reg[23] |= PSL_C; /* RFLAGS */ 261 } 262 263 /* set return parameters */ 264 reg[14] = rval[0]; /* RAX */ 265 if (error == 0) 266 reg[ 2] = rval[1]; /* RDX */ 267 268 //dump_regs(reg); 269 } 270 271 register_t 272 md_get_pc(ucontext_t *ucp) 273 { 274 register_t *reg = (register_t *) &ucp->uc_mcontext; 275 276 return reg[21]; /* RIP */ 277 } 278 279 register_t 280 md_get_sp(ucontext_t *ucp) 281 { 282 register_t *reg = (register_t *) &ucp->uc_mcontext; 283 284 return reg[24]; /* RSP */ 285 } 286 287 int 288 md_syscall_check_opcode(ucontext_t *ucp) 289 { 290 uint32_t opcode; 291 292 md_syscall_get_opcode(ucp, &opcode); 293 294 switch (opcode) { 295 case 0xff0f: /* UD1 */ 296 case 0xff0b: /* UD2 */ 297 case 0x80cd: /* int $80 */ 298 case 0x340f: /* sysenter */ 299 case 0x050f: /* syscall */ 300 return 1; 301 default: 302 return 0; 303 } 304 } 305 306 307 void 308 md_syscall_get_opcode(ucontext_t *ucp, uint32_t *opcode) 309 { 310 register_t *reg = (register_t *) &ucp->uc_mcontext; 311 // uint8_t *p8 = (uint8_t *) (reg[21]); 312 uint16_t *p16 = (uint16_t*) (reg[21]); /* RIP */ 313 314 switch (*p16) { 315 case 0xff0f: /* UD1 */ 316 case 0xff0b: /* UD2 */ 317 case 0x80cd: /* int $80 */ 318 case 0x340f: /* sysenter */ 319 case 0x050f: /* syscall */ 320 *opcode = *p16; 321 break; 322 default: 323 *opcode = 0; 324 } 325 } 326 327 void 328 md_syscall_inc_pc(ucontext_t *ucp, uint32_t opcode) 329 { 330 register_t *reg = (register_t *) &ucp->uc_mcontext; 331 332 /* advance program counter */ 333 switch (opcode) { 334 case 0xff0f: /* UD1 */ 335 case 0xff0b: /* UD2 */ 336 case 0x80cd: /* int $80 */ 337 case 0x340f: /* sysenter */ 338 case 0x050f: /* syscall */ 339 reg[21] += 2; /* RIP */ 340 break; 341 default: 342 panic("%s, unknown illegal instruction: opcode = %x\n", 343 __func__, (uint32_t) opcode); 344 } 345 } 346 347 void 348 md_syscall_dec_pc(ucontext_t *ucp, uint32_t opcode) 349 { 350 register_t *reg = (register_t *) &ucp->uc_mcontext; 351 352 switch (opcode) { 353 case 0xff0f: /* UD1 */ 354 case 0xff0b: /* UD2 */ 355 case 0x80cd: /* int $80 */ 356 case 0x340f: /* sysenter */ 357 case 0x050f: /* syscall */ 358 reg[21] -= 2; /* RIP */ 359 break; 360 default: 361 panic("%s, unknown illegal instruction: opcode = %x\n", 362 __func__, (uint32_t) opcode); 363 } 364 } 365 366
Indexes created Wed Oct 29 12:09:47 GMT 2025