xref: /netbsd-src/sys/compat/linux/arch/amd64/linux_machdep.c (revision 75219f3a016dfaad1cb304eb017f9787b1de8292)
1 /*	$NetBSD: linux_machdep.c,v 1.42 2013/11/18 01:32:32 chs Exp $ */
2 
3 /*-
4  * Copyright (c) 2005 Emmanuel Dreyfus, all rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Emmanuel Dreyfus
17  * 4. The name of the author may not be used to endorse or promote
18  *    products derived from this software without specific prior written
19  *    permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR AND CONTRIBUTORS ``AS IS''
22  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 
36 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.42 2013/11/18 01:32:32 chs Exp $");
37 
38 #include <sys/param.h>
39 #include <sys/types.h>
40 #include <sys/systm.h>
41 #include <sys/signal.h>
42 #include <sys/exec.h>
43 #include <sys/proc.h>
44 #include <sys/ptrace.h> /* for process_read_fpregs() */
45 #include <sys/ucontext.h>
46 #include <sys/conf.h>
47 #include <sys/pcu.h>
48 
49 #include <machine/reg.h>
50 #include <machine/pcb.h>
51 #include <machine/fpu.h>
52 #include <machine/mcontext.h>
53 #include <machine/specialreg.h>
54 #include <machine/vmparam.h>
55 #include <machine/cpufunc.h>
56 
57 /*
58  * To see whether wscons is configured (for virtual console ioctl calls).
59  */
60 #if defined(_KERNEL_OPT)
61 #include "wsdisplay.h"
62 #endif
63 #if (NWSDISPLAY > 0)
64 #include <dev/wscons/wsconsio.h>
65 #include <dev/wscons/wsdisplay_usl_io.h>
66 #endif
67 
68 extern const pcu_ops_t fpu_ops;
69 
70 #include <compat/linux/common/linux_signal.h>
71 #include <compat/linux/common/linux_errno.h>
72 #include <compat/linux/common/linux_exec.h>
73 #include <compat/linux/common/linux_ioctl.h>
74 #include <compat/linux/common/linux_prctl.h>
75 #include <compat/linux/common/linux_machdep.h>
76 #include <compat/linux/common/linux_ipc.h>
77 #include <compat/linux/common/linux_sem.h>
78 #include <compat/linux/linux_syscall.h>
79 #include <compat/linux/linux_syscallargs.h>
80 
81 static void linux_buildcontext(struct lwp *, void *, void *);
82 
83 void
84 linux_setregs(struct lwp *l, struct exec_package *epp, vaddr_t stack)
85 {
86 	struct pcb *pcb = lwp_getpcb(l);
87 	struct trapframe *tf;
88 
89 	pcu_discard(&fpu_ops, false);
90 
91 	pcb->pcb_flags = 0;
92 	pcb->pcb_savefpu.fp_fxsave.fx_fcw = __NetBSD_NPXCW__;
93 	pcb->pcb_savefpu.fp_fxsave.fx_mxcsr = __INITIAL_MXCSR__;
94 	pcb->pcb_savefpu.fp_fxsave.fx_mxcsr_mask = __INITIAL_MXCSR_MASK__;
95 
96 	l->l_proc->p_flag &= ~PK_32;
97 
98 	tf = l->l_md.md_regs;
99 	tf->tf_rax = 0;
100 	tf->tf_rbx = 0;
101 	tf->tf_rcx = epp->ep_entry;
102 	tf->tf_rdx = 0;
103 	tf->tf_rsi = 0;
104 	tf->tf_rdi = 0;
105 	tf->tf_rbp = 0;
106 	tf->tf_rsp = stack;
107 	tf->tf_r8 = 0;
108 	tf->tf_r9 = 0;
109 	tf->tf_r10 = 0;
110 	tf->tf_r11 = 0;
111 	tf->tf_r12 = 0;
112 	tf->tf_r13 = 0;
113 	tf->tf_r14 = 0;
114 	tf->tf_r15 = 0;
115 	tf->tf_rip = epp->ep_entry;
116 	tf->tf_rflags = PSL_USERSET;
117 	tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL);
118 	tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL);
119 	tf->tf_ds = GSEL(GUDATA_SEL, SEL_UPL);
120 	tf->tf_es = 0;
121 	cpu_fsgs_zero(l);
122 
123 	return;
124 }
125 
126 void
127 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
128 {
129 	struct lwp *l = curlwp;
130 	struct proc *p = l->l_proc;
131 	struct pcb *pcb = lwp_getpcb(l);
132 	struct sigacts *ps = p->p_sigacts;
133 	int onstack, error;
134 	int sig = ksi->ksi_signo;
135 	struct linux_rt_sigframe *sfp, sigframe;
136 	struct linux__fpstate *fpsp, fpstate;
137 	struct fpreg fpregs;
138 	struct trapframe *tf = l->l_md.md_regs;
139 	sig_t catcher = SIGACTION(p, sig).sa_handler;
140 	linux_sigset_t lmask;
141 	char *sp;
142 
143 	/* Do we need to jump onto the signal stack? */
144 	onstack =
145 	    (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
146 	    (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
147 
148 	/* Allocate space for the signal handler context. */
149 	if (onstack)
150 		sp = ((char *)l->l_sigstk.ss_sp +
151 		    l->l_sigstk.ss_size);
152 	else
153 		sp = (char *)tf->tf_rsp - 128;
154 
155 	/*
156 	 * Save FPU state, if any
157 	 */
158 	if (pcu_used_p(&fpu_ops)) {
159 		sp = (char *)
160 		    (((long)sp - sizeof(struct linux__fpstate)) & ~0xfUL);
161 		fpsp = (struct linux__fpstate *)sp;
162 	} else
163 		fpsp = NULL;
164 
165 	/*
166 	 * Populate the rt_sigframe
167 	 */
168 	sp = (char *)
169 	    ((((long)sp - sizeof(struct linux_rt_sigframe)) & ~0xfUL) - 8);
170 	sfp = (struct linux_rt_sigframe *)sp;
171 
172 	memset(&sigframe, 0, sizeof(sigframe));
173 	if (ps->sa_sigdesc[sig].sd_vers != 0)
174 		sigframe.pretcode =
175 		    (char *)(u_long)ps->sa_sigdesc[sig].sd_tramp;
176 	else
177 		sigframe.pretcode = NULL;
178 
179 	/*
180 	 * The user context
181 	 */
182 	sigframe.uc.luc_flags = 0;
183 	sigframe.uc.luc_link = NULL;
184 
185 	/* This is used regardless of SA_ONSTACK in Linux */
186 	sigframe.uc.luc_stack.ss_sp = l->l_sigstk.ss_sp;
187 	sigframe.uc.luc_stack.ss_size = l->l_sigstk.ss_size;
188 	sigframe.uc.luc_stack.ss_flags = 0;
189 	if (l->l_sigstk.ss_flags & SS_ONSTACK)
190 		sigframe.uc.luc_stack.ss_flags |= LINUX_SS_ONSTACK;
191 	if (l->l_sigstk.ss_flags & SS_DISABLE)
192 		sigframe.uc.luc_stack.ss_flags |= LINUX_SS_DISABLE;
193 
194 	sigframe.uc.luc_mcontext.r8 = tf->tf_r8;
195 	sigframe.uc.luc_mcontext.r9 = tf->tf_r9;
196 	sigframe.uc.luc_mcontext.r10 = tf->tf_r10;
197 	sigframe.uc.luc_mcontext.r11 = tf->tf_r11;
198 	sigframe.uc.luc_mcontext.r12 = tf->tf_r12;
199 	sigframe.uc.luc_mcontext.r13 = tf->tf_r13;
200 	sigframe.uc.luc_mcontext.r14 = tf->tf_r14;
201 	sigframe.uc.luc_mcontext.r15 = tf->tf_r15;
202 	sigframe.uc.luc_mcontext.rdi = tf->tf_rdi;
203 	sigframe.uc.luc_mcontext.rsi = tf->tf_rsi;
204 	sigframe.uc.luc_mcontext.rbp = tf->tf_rbp;
205 	sigframe.uc.luc_mcontext.rbx = tf->tf_rbx;
206 	sigframe.uc.luc_mcontext.rdx = tf->tf_rdx;
207 	sigframe.uc.luc_mcontext.rax = tf->tf_rax;
208 	sigframe.uc.luc_mcontext.rcx = tf->tf_rcx;
209 	sigframe.uc.luc_mcontext.rsp = tf->tf_rsp;
210 	sigframe.uc.luc_mcontext.rip = tf->tf_rip;
211 	sigframe.uc.luc_mcontext.eflags = tf->tf_rflags;
212 	sigframe.uc.luc_mcontext.cs = tf->tf_cs;
213 	sigframe.uc.luc_mcontext.gs = tf->tf_gs;
214 	sigframe.uc.luc_mcontext.fs = tf->tf_fs;
215 	sigframe.uc.luc_mcontext.err = tf->tf_err;
216 	sigframe.uc.luc_mcontext.trapno = tf->tf_trapno;
217 	native_to_linux_sigset(&lmask, mask);
218 	sigframe.uc.luc_mcontext.oldmask = lmask.sig[0];
219 	sigframe.uc.luc_mcontext.cr2 = (long)pcb->pcb_onfault;
220 	sigframe.uc.luc_mcontext.fpstate = fpsp;
221 	native_to_linux_sigset(&sigframe.uc.luc_sigmask, mask);
222 	native_to_linux_siginfo(&sigframe.info, &ksi->ksi_info);
223 	sendsig_reset(l, sig);
224 	mutex_exit(p->p_lock);
225 	error = 0;
226 
227 	/*
228 	 * Save FPU state, if any
229 	 */
230 	if (fpsp != NULL) {
231 		(void)process_read_fpregs(l, &fpregs);
232 		memset(&fpstate, 0, sizeof(fpstate));
233 		fpstate.cwd = fpregs.fp_fcw;
234 		fpstate.swd = fpregs.fp_fsw;
235 		fpstate.twd = fpregs.fp_ftw;
236 		fpstate.fop = fpregs.fp_fop;
237 		fpstate.rip = fpregs.fp_rip;
238 		fpstate.rdp = fpregs.fp_rdp;
239 		fpstate.mxcsr = fpregs.fp_mxcsr;
240 		fpstate.mxcsr_mask = fpregs.fp_mxcsr_mask;
241 		memcpy(&fpstate.st_space, &fpregs.fp_st,
242 		    sizeof(fpstate.st_space));
243 		memcpy(&fpstate.xmm_space, &fpregs.fp_xmm,
244 		    sizeof(fpstate.xmm_space));
245 		error = copyout(&fpstate, fpsp, sizeof(fpstate));
246 	}
247 
248 	if (error == 0)
249 		error = copyout(&sigframe, sp, sizeof(sigframe));
250 
251 	mutex_enter(p->p_lock);
252 
253 	if (error != 0) {
254 		sigexit(l, SIGILL);
255 		return;
256 	}
257 
258 	linux_buildcontext(l, catcher, sp);
259 	tf->tf_rdi = sigframe.info.lsi_signo;
260 	tf->tf_rax = 0;
261 	tf->tf_rsi = (long)&sfp->info;
262 	tf->tf_rdx = (long)&sfp->uc;
263 
264 	/*
265 	 * Remember we use signal stack
266 	 */
267 	if (onstack)
268 		l->l_sigstk.ss_flags |= SS_ONSTACK;
269 	return;
270 }
271 
272 int
273 linux_sys_modify_ldt(struct lwp *l, const struct linux_sys_modify_ldt_args *v, register_t *retval)
274 {
275 	printf("linux_sys_modify_ldt\n");
276 	return 0;
277 }
278 
279 int
280 linux_sys_iopl(struct lwp *l, const struct linux_sys_iopl_args *v, register_t *retval)
281 {
282 	return 0;
283 }
284 
285 int
286 linux_sys_ioperm(struct lwp *l, const struct linux_sys_ioperm_args *v, register_t *retval)
287 {
288 	return 0;
289 }
290 
291 dev_t
292 linux_fakedev(dev_t dev, int raw)
293 {
294 
295        extern const struct cdevsw ptc_cdevsw, pts_cdevsw;
296        const struct cdevsw *cd = cdevsw_lookup(dev);
297 
298        if (raw) {
299 #if (NWSDISPLAY > 0)
300 	       extern const struct cdevsw wsdisplay_cdevsw;
301 	       if (cd == &wsdisplay_cdevsw)
302 		       return makedev(LINUX_CONS_MAJOR, (minor(dev) + 1));
303 #endif
304        }
305 
306        if (cd == &ptc_cdevsw)
307 	       return makedev(LINUX_PTC_MAJOR, minor(dev));
308        if (cd == &pts_cdevsw)
309 	       return makedev(LINUX_PTS_MAJOR, minor(dev));
310 
311 	return ((minor(dev) & 0xff) | ((major(dev) & 0xfff) << 8)
312 	    | (((unsigned long long int) (minor(dev) & ~0xff)) << 12)
313 	    | (((unsigned long long int) (major(dev) & ~0xfff)) << 32));
314 }
315 
316 int
317 linux_machdepioctl(struct lwp *l, const struct linux_sys_ioctl_args *v, register_t *retval)
318 {
319 	return 0;
320 }
321 
322 int
323 linux_sys_rt_sigreturn(struct lwp *l, const void *v, register_t *retval)
324 {
325 	struct linux_ucontext *luctx;
326 	struct trapframe *tf = l->l_md.md_regs;
327 	struct linux_sigcontext *lsigctx;
328 	struct linux__fpstate fpstate;
329 	struct linux_rt_sigframe frame, *fp;
330 	ucontext_t uctx;
331 	mcontext_t *mctx;
332 	struct fxsave64 *fxarea;
333 	int error;
334 
335 	fp = (struct linux_rt_sigframe *)(tf->tf_rsp - 8);
336 	if ((error = copyin(fp, &frame, sizeof(frame))) != 0) {
337 		mutex_enter(l->l_proc->p_lock);
338 		sigexit(l, SIGILL);
339 		return error;
340 	}
341 	luctx = &frame.uc;
342 	lsigctx = &luctx->luc_mcontext;
343 
344 	memset(&uctx, 0, sizeof(uctx));
345 	mctx = (mcontext_t *)&uctx.uc_mcontext;
346 	fxarea = (struct fxsave64 *)&mctx->__fpregs;
347 
348 	/*
349 	 * Set the flags. Linux always have CPU, stack and signal state,
350 	 * FPU is optional. uc_flags is not used to tell what we have.
351 	 */
352 	uctx.uc_flags = (_UC_SIGMASK|_UC_CPU|_UC_STACK|_UC_CLRSTACK);
353 	if (lsigctx->fpstate != NULL)
354 		uctx.uc_flags |= _UC_FPU;
355 	uctx.uc_link = NULL;
356 
357 	/*
358 	 * Signal set
359 	 */
360 	linux_to_native_sigset(&uctx.uc_sigmask, &luctx->luc_sigmask);
361 
362 	/*
363 	 * CPU state
364 	 */
365 	mctx->__gregs[_REG_R8] = lsigctx->r8;
366 	mctx->__gregs[_REG_R9] = lsigctx->r9;
367 	mctx->__gregs[_REG_R10] = lsigctx->r10;
368 	mctx->__gregs[_REG_R11] = lsigctx->r11;
369 	mctx->__gregs[_REG_R12] = lsigctx->r12;
370 	mctx->__gregs[_REG_R13] = lsigctx->r13;
371 	mctx->__gregs[_REG_R14] = lsigctx->r14;
372 	mctx->__gregs[_REG_R15] = lsigctx->r15;
373 	mctx->__gregs[_REG_RDI] = lsigctx->rdi;
374 	mctx->__gregs[_REG_RSI] = lsigctx->rsi;
375 	mctx->__gregs[_REG_RBP] = lsigctx->rbp;
376 	mctx->__gregs[_REG_RBX] = lsigctx->rbx;
377 	mctx->__gregs[_REG_RAX] = lsigctx->rax;
378 	mctx->__gregs[_REG_RDX] = lsigctx->rdx;
379 	mctx->__gregs[_REG_RCX] = lsigctx->rcx;
380 	mctx->__gregs[_REG_RIP] = lsigctx->rip;
381 	mctx->__gregs[_REG_RFLAGS] = lsigctx->eflags;
382 	mctx->__gregs[_REG_CS] = lsigctx->cs;
383 	mctx->__gregs[_REG_GS] = lsigctx->gs;
384 	mctx->__gregs[_REG_FS] = lsigctx->fs;
385 	mctx->__gregs[_REG_ERR] = lsigctx->err;
386 	mctx->__gregs[_REG_TRAPNO] = lsigctx->trapno;
387 	mctx->__gregs[_REG_ES] = tf->tf_es;
388 	mctx->__gregs[_REG_DS] = tf->tf_ds;
389 	mctx->__gregs[_REG_RSP] = lsigctx->rsp; /* XXX */
390 	mctx->__gregs[_REG_SS] = tf->tf_ss;
391 
392 	/*
393 	 * FPU state
394 	 */
395 	if (lsigctx->fpstate != NULL) {
396 		error = copyin(lsigctx->fpstate, &fpstate, sizeof(fpstate));
397 		if (error != 0) {
398 			mutex_enter(l->l_proc->p_lock);
399 			sigexit(l, SIGILL);
400 			return error;
401 		}
402 
403 		fxarea->fx_fcw = fpstate.cwd;
404 		fxarea->fx_fsw = fpstate.swd;
405 		fxarea->fx_ftw = fpstate.twd;
406 		fxarea->fx_fop = fpstate.fop;
407 		fxarea->fx_rip = fpstate.rip;
408 		fxarea->fx_rdp = fpstate.rdp;
409 		fxarea->fx_mxcsr = fpstate.mxcsr;
410 		fxarea->fx_mxcsr_mask = fpstate.mxcsr_mask;
411 		memcpy(&fxarea->fx_st, &fpstate.st_space,
412 		    sizeof(fxarea->fx_st));
413 		memcpy(&fxarea->fx_xmm, &fpstate.xmm_space,
414 		    sizeof(fxarea->fx_xmm));
415 	}
416 
417 	/*
418 	 * And the stack
419 	 */
420 	uctx.uc_stack.ss_flags = 0;
421 	if (luctx->luc_stack.ss_flags & LINUX_SS_ONSTACK)
422 		uctx.uc_stack.ss_flags |= SS_ONSTACK;
423 
424 	if (luctx->luc_stack.ss_flags & LINUX_SS_DISABLE)
425 		uctx.uc_stack.ss_flags |= SS_DISABLE;
426 
427 	uctx.uc_stack.ss_sp = luctx->luc_stack.ss_sp;
428 	uctx.uc_stack.ss_size = luctx->luc_stack.ss_size;
429 
430 	/*
431 	 * And let setucontext deal with that.
432 	 */
433 	mutex_enter(l->l_proc->p_lock);
434 	error = setucontext(l, &uctx);
435 	mutex_exit(l->l_proc->p_lock);
436 	if (error)
437 		return error;
438 
439 	return EJUSTRETURN;
440 }
441 
442 int
443 linux_sys_arch_prctl(struct lwp *l,
444     const struct linux_sys_arch_prctl_args *uap, register_t *retval)
445 {
446 	/* {
447 		syscallarg(int) code;
448 		syscallarg(unsigned long) addr;
449 	} */
450 	void *addr = (void *)SCARG(uap, addr);
451 
452 	switch(SCARG(uap, code)) {
453 	case LINUX_ARCH_SET_GS:
454 		return x86_set_sdbase(addr, 'g', l, true);
455 
456 	case LINUX_ARCH_GET_GS:
457 		return x86_get_sdbase(addr, 'g');
458 
459 	case LINUX_ARCH_SET_FS:
460 		return x86_set_sdbase(addr, 'f', l, true);
461 
462 	case LINUX_ARCH_GET_FS:
463 		return x86_get_sdbase(addr, 'f');
464 
465 	default:
466 #ifdef DEBUG_LINUX
467 		printf("linux_sys_arch_prctl: unexpected code %d\n",
468 		    SCARG(uap, code));
469 #endif
470 		return EINVAL;
471 	}
472 	/* NOTREACHED */
473 }
474 
475 const int linux_vsyscall_to_syscall[] = {
476 	LINUX_SYS_gettimeofday,
477 	LINUX_SYS_time,
478 	LINUX_SYS_nosys,	/* nosys */
479 	LINUX_SYS_nosys,	/* nosys */
480 };
481 
482 int
483 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg)
484 {
485 	struct trapframe *tf = arg;
486 	uint64_t retaddr;
487 	int vsyscallnr;
488 
489 	/*
490 	 * Check for a vsyscall. %rip must be the fault address,
491 	 * and the address must be in the Linux vsyscall area.
492 	 * Also, vsyscalls are only done at 1024-byte boundaries.
493 	 */
494 
495 	if (__predict_true(trapaddr < LINUX_VSYSCALL_START))
496 		return 0;
497 
498 	if (trapaddr != tf->tf_rip)
499 		return 0;
500 
501 	if ((tf->tf_rip & (LINUX_VSYSCALL_SIZE - 1)) != 0)
502 		return 0;
503 
504 	vsyscallnr = (tf->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SIZE;
505 
506 	if (vsyscallnr > LINUX_VSYSCALL_MAXNR)
507 		return 0;
508 
509 	/*
510 	 * Get the return address from the top of the stack,
511 	 * and fix up the return address.
512 	 * This assumes the faulting instruction was callq *reg,
513 	 * which is the only way that vsyscalls are ever entered.
514 	 */
515 	if (copyin((void *)tf->tf_rsp, &retaddr, sizeof retaddr) != 0)
516 		return 0;
517 	tf->tf_rip = retaddr;
518 	tf->tf_rax = linux_vsyscall_to_syscall[vsyscallnr];
519 	tf->tf_rsp += 8;	/* "pop" the return address */
520 
521 #if 0
522 	printf("usertrap: rip %p rsp %p retaddr %p vsys %d sys %d\n",
523 	    (void *)tf->tf_rip, (void *)tf->tf_rsp, (void *)retaddr,
524 	    vsyscallnr, (int)tf->tf_rax);
525 #endif
526 
527 	(*l->l_proc->p_md.md_syscall)(tf);
528 
529 	return 1;
530 }
531 
532 static void
533 linux_buildcontext(struct lwp *l, void *catcher, void *f)
534 {
535 	struct trapframe *tf = l->l_md.md_regs;
536 
537 	tf->tf_ds = GSEL(GUDATA_SEL, SEL_UPL);
538 	tf->tf_rip = (u_int64_t)catcher;
539 	tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL);
540 	tf->tf_rflags &= ~PSL_CLEARSIG;
541 	tf->tf_rsp = (u_int64_t)f;
542 	tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL);
543 }
544