Index: stable/10/sys/amd64/amd64/machdep.c
===================================================================
--- stable/10/sys/amd64/amd64/machdep.c	(revision 292550)
+++ stable/10/sys/amd64/amd64/machdep.c	(revision 292551)
@@ -1,2784 +1,2795 @@
 /*-
  * Copyright (c) 2003 Peter Wemm.
  * Copyright (c) 1992 Terrence R. Lambert.
  * Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
  * All rights reserved.
  *
  * This code is derived from software contributed to Berkeley by
  * William Jolitz.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. All advertising materials mentioning features or use of this software
  *    must display the following acknowledgement:
  *	This product includes software developed by the University of
  *	California, Berkeley and its contributors.
  * 4. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  *	from: @(#)machdep.c	7.4 (Berkeley) 6/3/91
  */
 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
 #include "opt_atalk.h"
 #include "opt_atpic.h"
 #include "opt_compat.h"
 #include "opt_cpu.h"
 #include "opt_ddb.h"
 #include "opt_inet.h"
 #include "opt_ipx.h"
 #include "opt_isa.h"
 #include "opt_kstack_pages.h"
 #include "opt_maxmem.h"
 #include "opt_mp_watchdog.h"
 #include "opt_perfmon.h"
 #include "opt_platform.h"
 #include "opt_sched.h"
 #include "opt_kdtrace.h"
 
 #include <sys/param.h>
 #include <sys/proc.h>
 #include <sys/systm.h>
 #include <sys/bio.h>
 #include <sys/buf.h>
 #include <sys/bus.h>
 #include <sys/callout.h>
 #include <sys/cons.h>
 #include <sys/cpu.h>
 #include <sys/efi.h>
 #include <sys/eventhandler.h>
 #include <sys/exec.h>
 #include <sys/imgact.h>
 #include <sys/kdb.h>
 #include <sys/kernel.h>
 #include <sys/ktr.h>
 #include <sys/linker.h>
 #include <sys/lock.h>
 #include <sys/malloc.h>
 #include <sys/memrange.h>
 #include <sys/msgbuf.h>
 #include <sys/mutex.h>
 #include <sys/pcpu.h>
 #include <sys/ptrace.h>
 #include <sys/reboot.h>
 #include <sys/rwlock.h>
 #include <sys/sched.h>
 #include <sys/signalvar.h>
 #ifdef SMP
 #include <sys/smp.h>
 #endif
 #include <sys/syscallsubr.h>
 #include <sys/sysctl.h>
 #include <sys/sysent.h>
 #include <sys/sysproto.h>
 #include <sys/ucontext.h>
 #include <sys/vmmeter.h>
 
 #include <vm/vm.h>
 #include <vm/vm_extern.h>
 #include <vm/vm_kern.h>
 #include <vm/vm_page.h>
 #include <vm/vm_map.h>
 #include <vm/vm_object.h>
 #include <vm/vm_pager.h>
 #include <vm/vm_param.h>
 
 #ifdef DDB
 #ifndef KDB
 #error KDB must be enabled in order for DDB to work!
 #endif
 #include <ddb/ddb.h>
 #include <ddb/db_sym.h>
 #endif
 
 #include <net/netisr.h>
 
 #include <machine/clock.h>
 #include <machine/cpu.h>
 #include <machine/cputypes.h>
 #include <machine/intr_machdep.h>
 #include <x86/mca.h>
 #include <machine/md_var.h>
 #include <machine/metadata.h>
 #include <machine/mp_watchdog.h>
 #include <machine/pc/bios.h>
 #include <machine/pcb.h>
 #include <machine/proc.h>
 #include <machine/reg.h>
 #include <machine/sigframe.h>
 #include <machine/specialreg.h>
 #ifdef PERFMON
 #include <machine/perfmon.h>
 #endif
 #include <machine/tss.h>
 #ifdef SMP
 #include <machine/smp.h>
 #endif
 #ifdef FDT
 #include <x86/fdt.h>
 #endif
 
 #ifdef DEV_ATPIC
 #include <x86/isa/icu.h>
 #else
 #include <machine/apicvar.h>
 #endif
 
 #include <isa/isareg.h>
 #include <isa/rtc.h>
 
 /* Sanity check for __curthread() */
 CTASSERT(offsetof(struct pcpu, pc_curthread) == 0);
 
 extern u_int64_t hammer_time(u_int64_t, u_int64_t);
 
 #define	CS_SECURE(cs)		(ISPL(cs) == SEL_UPL)
 #define	EFL_SECURE(ef, oef)	((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
 
 static void cpu_startup(void *);
 static void get_fpcontext(struct thread *td, mcontext_t *mcp,
     char *xfpusave, size_t xfpusave_len);
 static int  set_fpcontext(struct thread *td, mcontext_t *mcp,
     char *xfpustate, size_t xfpustate_len);
 SYSINIT(cpu, SI_SUB_CPU, SI_ORDER_FIRST, cpu_startup, NULL);
 
 /*
  * The file "conf/ldscript.amd64" defines the symbol "kernphys".  Its value is
  * the physical address at which the kernel is loaded.
  */
 extern char kernphys[];
 #ifdef DDB
 extern vm_offset_t ksym_start, ksym_end;
 #endif
 
 struct msgbuf *msgbufp;
 
 /* Intel ICH registers */
 #define ICH_PMBASE	0x400
 #define ICH_SMI_EN	ICH_PMBASE + 0x30
 
 int	_udatasel, _ucodesel, _ucode32sel, _ufssel, _ugssel;
 
 int cold = 1;
 
 long Maxmem = 0;
 long realmem = 0;
 
 /*
  * The number of PHYSMAP entries must be one less than the number of
  * PHYSSEG entries because the PHYSMAP entry that spans the largest
  * physical address that is accessible by ISA DMA is split into two
  * PHYSSEG entries.
  */
 #define	PHYSMAP_SIZE	(2 * (VM_PHYSSEG_MAX - 1))
 
 vm_paddr_t phys_avail[PHYSMAP_SIZE + 2];
 vm_paddr_t dump_avail[PHYSMAP_SIZE + 2];
 
 /* must be 2 less so 0 0 can signal end of chunks */
 #define PHYS_AVAIL_ARRAY_END ((sizeof(phys_avail) / sizeof(phys_avail[0])) - 2)
 #define DUMP_AVAIL_ARRAY_END ((sizeof(dump_avail) / sizeof(dump_avail[0])) - 2)
 
 struct kva_md_info kmi;
 
 static struct trapframe proc0_tf;
 struct region_descriptor r_gdt, r_idt;
 
 struct pcpu __pcpu[MAXCPU];
 
 struct mtx icu_lock;
 
 struct mem_range_softc mem_range_softc;
 
 struct mtx dt_lock;	/* lock for GDT and LDT */
 
 void (*vmm_resume_p)(void);
 
 static void
 cpu_startup(dummy)
 	void *dummy;
 {
 	uintmax_t memsize;
 	char *sysenv;
 
 	/*
 	 * On MacBooks, we need to disallow the legacy USB circuit to
 	 * generate an SMI# because this can cause several problems,
 	 * namely: incorrect CPU frequency detection and failure to
 	 * start the APs.
 	 * We do this by disabling a bit in the SMI_EN (SMI Control and
 	 * Enable register) of the Intel ICH LPC Interface Bridge. 
 	 */
 	sysenv = getenv("smbios.system.product");
 	if (sysenv != NULL) {
 		if (strncmp(sysenv, "MacBook1,1", 10) == 0 ||
 		    strncmp(sysenv, "MacBook3,1", 10) == 0 ||
 		    strncmp(sysenv, "MacBook4,1", 10) == 0 ||
 		    strncmp(sysenv, "MacBookPro1,1", 13) == 0 ||
 		    strncmp(sysenv, "MacBookPro1,2", 13) == 0 ||
 		    strncmp(sysenv, "MacBookPro3,1", 13) == 0 ||
 		    strncmp(sysenv, "MacBookPro4,1", 13) == 0 ||
 		    strncmp(sysenv, "Macmini1,1", 10) == 0) {
 			if (bootverbose)
 				printf("Disabling LEGACY_USB_EN bit on "
 				    "Intel ICH.\n");
 			outl(ICH_SMI_EN, inl(ICH_SMI_EN) & ~0x8);
 		}
 		freeenv(sysenv);
 	}
 
 	/*
 	 * Good {morning,afternoon,evening,night}.
 	 */
 	startrtclock();
 	printcpuinfo();
 	panicifcpuunsupported();
 #ifdef PERFMON
 	perfmon_init();
 #endif
 
 	/*
 	 * Display physical memory if SMBIOS reports reasonable amount.
 	 */
 	memsize = 0;
 	sysenv = getenv("smbios.memory.enabled");
 	if (sysenv != NULL) {
 		memsize = (uintmax_t)strtoul(sysenv, (char **)NULL, 10) << 10;
 		freeenv(sysenv);
 	}
 	if (memsize < ptoa((uintmax_t)cnt.v_free_count))
 		memsize = ptoa((uintmax_t)Maxmem);
 	printf("real memory  = %ju (%ju MB)\n", memsize, memsize >> 20);
 	realmem = atop(memsize);
 
 	/*
 	 * Display any holes after the first chunk of extended memory.
 	 */
 	if (bootverbose) {
 		int indx;
 
 		printf("Physical memory chunk(s):\n");
 		for (indx = 0; phys_avail[indx + 1] != 0; indx += 2) {
 			vm_paddr_t size;
 
 			size = phys_avail[indx + 1] - phys_avail[indx];
 			printf(
 			    "0x%016jx - 0x%016jx, %ju bytes (%ju pages)\n",
 			    (uintmax_t)phys_avail[indx],
 			    (uintmax_t)phys_avail[indx + 1] - 1,
 			    (uintmax_t)size, (uintmax_t)size / PAGE_SIZE);
 		}
 	}
 
 	vm_ksubmap_init(&kmi);
 
 	printf("avail memory = %ju (%ju MB)\n",
 	    ptoa((uintmax_t)cnt.v_free_count),
 	    ptoa((uintmax_t)cnt.v_free_count) / 1048576);
 
 	/*
 	 * Set up buffers, so they can be used to read disk labels.
 	 */
 	bufinit();
 	vm_pager_bufferinit();
 
 	cpu_setregs();
 }
 
 /*
  * Send an interrupt to process.
  *
  * Stack is set up to allow sigcode stored
  * at top to call routine, followed by call
  * to sigreturn routine below.  After sigreturn
  * resets the signal mask, the stack, and the
  * frame pointer, it returns to the user
  * specified pc, psl.
  */
 void
 sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
 {
 	struct sigframe sf, *sfp;
 	struct pcb *pcb;
 	struct proc *p;
 	struct thread *td;
 	struct sigacts *psp;
 	char *sp;
 	struct trapframe *regs;
 	char *xfpusave;
 	size_t xfpusave_len;
 	int sig;
 	int oonstack;
 
 	td = curthread;
 	pcb = td->td_pcb;
 	p = td->td_proc;
 	PROC_LOCK_ASSERT(p, MA_OWNED);
 	sig = ksi->ksi_signo;
 	psp = p->p_sigacts;
 	mtx_assert(&psp->ps_mtx, MA_OWNED);
 	regs = td->td_frame;
 	oonstack = sigonstack(regs->tf_rsp);
 
 	if (cpu_max_ext_state_size > sizeof(struct savefpu) && use_xsave) {
 		xfpusave_len = cpu_max_ext_state_size - sizeof(struct savefpu);
 		xfpusave = __builtin_alloca(xfpusave_len);
 	} else {
 		xfpusave_len = 0;
 		xfpusave = NULL;
 	}
 
 	/* Save user context. */
 	bzero(&sf, sizeof(sf));
 	sf.sf_uc.uc_sigmask = *mask;
 	sf.sf_uc.uc_stack = td->td_sigstk;
 	sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
 	    ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
 	sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
 	bcopy(regs, &sf.sf_uc.uc_mcontext.mc_rdi, sizeof(*regs));
 	sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
 	get_fpcontext(td, &sf.sf_uc.uc_mcontext, xfpusave, xfpusave_len);
 	fpstate_drop(td);
 	sf.sf_uc.uc_mcontext.mc_fsbase = pcb->pcb_fsbase;
 	sf.sf_uc.uc_mcontext.mc_gsbase = pcb->pcb_gsbase;
 	bzero(sf.sf_uc.uc_mcontext.mc_spare,
 	    sizeof(sf.sf_uc.uc_mcontext.mc_spare));
 	bzero(sf.sf_uc.__spare__, sizeof(sf.sf_uc.__spare__));
 
 	/* Allocate space for the signal handler context. */
 	if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
 	    SIGISMEMBER(psp->ps_sigonstack, sig)) {
 		sp = td->td_sigstk.ss_sp + td->td_sigstk.ss_size;
 #if defined(COMPAT_43)
 		td->td_sigstk.ss_flags |= SS_ONSTACK;
 #endif
 	} else
 		sp = (char *)regs->tf_rsp - 128;
 	if (xfpusave != NULL) {
 		sp -= xfpusave_len;
 		sp = (char *)((unsigned long)sp & ~0x3Ful);
 		sf.sf_uc.uc_mcontext.mc_xfpustate = (register_t)sp;
 	}
 	sp -= sizeof(struct sigframe);
 	/* Align to 16 bytes. */
 	sfp = (struct sigframe *)((unsigned long)sp & ~0xFul);
 
 	/* Translate the signal if appropriate. */
 	if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
 		sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
 
 	/* Build the argument list for the signal handler. */
 	regs->tf_rdi = sig;			/* arg 1 in %rdi */
 	regs->tf_rdx = (register_t)&sfp->sf_uc;	/* arg 3 in %rdx */
 	bzero(&sf.sf_si, sizeof(sf.sf_si));
 	if (SIGISMEMBER(psp->ps_siginfo, sig)) {
 		/* Signal handler installed with SA_SIGINFO. */
 		regs->tf_rsi = (register_t)&sfp->sf_si;	/* arg 2 in %rsi */
 		sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
 
 		/* Fill in POSIX parts */
 		sf.sf_si = ksi->ksi_info;
 		sf.sf_si.si_signo = sig; /* maybe a translated signal */
 		regs->tf_rcx = (register_t)ksi->ksi_addr; /* arg 4 in %rcx */
 	} else {
 		/* Old FreeBSD-style arguments. */
 		regs->tf_rsi = ksi->ksi_code;	/* arg 2 in %rsi */
 		regs->tf_rcx = (register_t)ksi->ksi_addr; /* arg 4 in %rcx */
 		sf.sf_ahu.sf_handler = catcher;
 	}
 	mtx_unlock(&psp->ps_mtx);
 	PROC_UNLOCK(p);
 
 	/*
 	 * Copy the sigframe out to the user's stack.
 	 */
 	if (copyout(&sf, sfp, sizeof(*sfp)) != 0 ||
 	    (xfpusave != NULL && copyout(xfpusave,
 	    (void *)sf.sf_uc.uc_mcontext.mc_xfpustate, xfpusave_len)
 	    != 0)) {
 #ifdef DEBUG
 		printf("process %ld has trashed its stack\n", (long)p->p_pid);
 #endif
 		PROC_LOCK(p);
 		sigexit(td, SIGILL);
 	}
 
 	regs->tf_rsp = (long)sfp;
 	regs->tf_rip = p->p_sysent->sv_sigcode_base;
 	regs->tf_rflags &= ~(PSL_T | PSL_D);
 	regs->tf_cs = _ucodesel;
 	regs->tf_ds = _udatasel;
 	regs->tf_ss = _udatasel;
 	regs->tf_es = _udatasel;
 	regs->tf_fs = _ufssel;
 	regs->tf_gs = _ugssel;
 	regs->tf_flags = TF_HASSEGS;
 	set_pcb_flags(pcb, PCB_FULL_IRET);
 	PROC_LOCK(p);
 	mtx_lock(&psp->ps_mtx);
 }
 
 /*
  * System call to cleanup state after a signal
  * has been taken.  Reset signal mask and
  * stack state from context left by sendsig (above).
  * Return to previous pc and psl as specified by
  * context left by sendsig. Check carefully to
  * make sure that the user has not modified the
  * state to gain improper privileges.
  *
  * MPSAFE
  */
 int
 sys_sigreturn(td, uap)
 	struct thread *td;
 	struct sigreturn_args /* {
 		const struct __ucontext *sigcntxp;
 	} */ *uap;
 {
 	ucontext_t uc;
 	struct pcb *pcb;
 	struct proc *p;
 	struct trapframe *regs;
 	ucontext_t *ucp;
 	char *xfpustate;
 	size_t xfpustate_len;
 	long rflags;
 	int cs, error, ret;
 	ksiginfo_t ksi;
 
 	pcb = td->td_pcb;
 	p = td->td_proc;
 
 	error = copyin(uap->sigcntxp, &uc, sizeof(uc));
 	if (error != 0) {
 		uprintf("pid %d (%s): sigreturn copyin failed\n",
 		    p->p_pid, td->td_name);
 		return (error);
 	}
 	ucp = &uc;
 	if ((ucp->uc_mcontext.mc_flags & ~_MC_FLAG_MASK) != 0) {
 		uprintf("pid %d (%s): sigreturn mc_flags %x\n", p->p_pid,
 		    td->td_name, ucp->uc_mcontext.mc_flags);
 		return (EINVAL);
 	}
 	regs = td->td_frame;
 	rflags = ucp->uc_mcontext.mc_rflags;
 	/*
 	 * Don't allow users to change privileged or reserved flags.
 	 */
 	if (!EFL_SECURE(rflags, regs->tf_rflags)) {
 		uprintf("pid %d (%s): sigreturn rflags = 0x%lx\n", p->p_pid,
 		    td->td_name, rflags);
 		return (EINVAL);
 	}
 
 	/*
 	 * Don't allow users to load a valid privileged %cs.  Let the
 	 * hardware check for invalid selectors, excess privilege in
 	 * other selectors, invalid %eip's and invalid %esp's.
 	 */
 	cs = ucp->uc_mcontext.mc_cs;
 	if (!CS_SECURE(cs)) {
 		uprintf("pid %d (%s): sigreturn cs = 0x%x\n", p->p_pid,
 		    td->td_name, cs);
 		ksiginfo_init_trap(&ksi);
 		ksi.ksi_signo = SIGBUS;
 		ksi.ksi_code = BUS_OBJERR;
 		ksi.ksi_trapno = T_PROTFLT;
 		ksi.ksi_addr = (void *)regs->tf_rip;
 		trapsignal(td, &ksi);
 		return (EINVAL);
 	}
 
 	if ((uc.uc_mcontext.mc_flags & _MC_HASFPXSTATE) != 0) {
 		xfpustate_len = uc.uc_mcontext.mc_xfpustate_len;
 		if (xfpustate_len > cpu_max_ext_state_size -
 		    sizeof(struct savefpu)) {
 			uprintf("pid %d (%s): sigreturn xfpusave_len = 0x%zx\n",
 			    p->p_pid, td->td_name, xfpustate_len);
 			return (EINVAL);
 		}
 		xfpustate = __builtin_alloca(xfpustate_len);
 		error = copyin((const void *)uc.uc_mcontext.mc_xfpustate,
 		    xfpustate, xfpustate_len);
 		if (error != 0) {
 			uprintf(
 	"pid %d (%s): sigreturn copying xfpustate failed\n",
 			    p->p_pid, td->td_name);
 			return (error);
 		}
 	} else {
 		xfpustate = NULL;
 		xfpustate_len = 0;
 	}
 	ret = set_fpcontext(td, &ucp->uc_mcontext, xfpustate, xfpustate_len);
 	if (ret != 0) {
 		uprintf("pid %d (%s): sigreturn set_fpcontext err %d\n",
 		    p->p_pid, td->td_name, ret);
 		return (ret);
 	}
 	bcopy(&ucp->uc_mcontext.mc_rdi, regs, sizeof(*regs));
 	pcb->pcb_fsbase = ucp->uc_mcontext.mc_fsbase;
 	pcb->pcb_gsbase = ucp->uc_mcontext.mc_gsbase;
 
 #if defined(COMPAT_43)
 	if (ucp->uc_mcontext.mc_onstack & 1)
 		td->td_sigstk.ss_flags |= SS_ONSTACK;
 	else
 		td->td_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
 	kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0);
 	set_pcb_flags(pcb, PCB_FULL_IRET);
 	return (EJUSTRETURN);
 }
 
 #ifdef COMPAT_FREEBSD4
 int
 freebsd4_sigreturn(struct thread *td, struct freebsd4_sigreturn_args *uap)
 {
  
 	return sys_sigreturn(td, (struct sigreturn_args *)uap);
 }
 #endif
 
 
 /*
  * Machine dependent boot() routine
  *
  * I haven't seen anything to put here yet
  * Possibly some stuff might be grafted back here from boot()
  */
 void
 cpu_boot(int howto)
 {
 }
 
 /*
  * Flush the D-cache for non-DMA I/O so that the I-cache can
  * be made coherent later.
  */
 void
 cpu_flush_dcache(void *ptr, size_t len)
 {
 	/* Not applicable */
 }
 
 /* Get current clock frequency for the given cpu id. */
 int
 cpu_est_clockrate(int cpu_id, uint64_t *rate)
 {
 	uint64_t tsc1, tsc2;
 	uint64_t acnt, mcnt, perf;
 	register_t reg;
 
 	if (pcpu_find(cpu_id) == NULL || rate == NULL)
 		return (EINVAL);
 
 	/*
 	 * If TSC is P-state invariant and APERF/MPERF MSRs do not exist,
 	 * DELAY(9) based logic fails.
 	 */
 	if (tsc_is_invariant && !tsc_perf_stat)
 		return (EOPNOTSUPP);
 
 #ifdef SMP
 	if (smp_cpus > 1) {
 		/* Schedule ourselves on the indicated cpu. */
 		thread_lock(curthread);
 		sched_bind(curthread, cpu_id);
 		thread_unlock(curthread);
 	}
 #endif
 
 	/* Calibrate by measuring a short delay. */
 	reg = intr_disable();
 	if (tsc_is_invariant) {
 		wrmsr(MSR_MPERF, 0);
 		wrmsr(MSR_APERF, 0);
 		tsc1 = rdtsc();
 		DELAY(1000);
 		mcnt = rdmsr(MSR_MPERF);
 		acnt = rdmsr(MSR_APERF);
 		tsc2 = rdtsc();
 		intr_restore(reg);
 		perf = 1000 * acnt / mcnt;
 		*rate = (tsc2 - tsc1) * perf;
 	} else {
 		tsc1 = rdtsc();
 		DELAY(1000);
 		tsc2 = rdtsc();
 		intr_restore(reg);
 		*rate = (tsc2 - tsc1) * 1000;
 	}
 
 #ifdef SMP
 	if (smp_cpus > 1) {
 		thread_lock(curthread);
 		sched_unbind(curthread);
 		thread_unlock(curthread);
 	}
 #endif
 
 	return (0);
 }
 
 /*
  * Shutdown the CPU as much as possible
  */
 void
 cpu_halt(void)
 {
 	for (;;)
 		halt();
 }
 
 void (*cpu_idle_hook)(sbintime_t) = NULL;	/* ACPI idle hook. */
 static int	cpu_ident_amdc1e = 0;	/* AMD C1E supported. */
 static int	idle_mwait = 1;		/* Use MONITOR/MWAIT for short idle. */
 TUNABLE_INT("machdep.idle_mwait", &idle_mwait);
 SYSCTL_INT(_machdep, OID_AUTO, idle_mwait, CTLFLAG_RW, &idle_mwait,
     0, "Use MONITOR/MWAIT for short idle");
 
 #define	STATE_RUNNING	0x0
 #define	STATE_MWAIT	0x1
 #define	STATE_SLEEPING	0x2
 
 static void
 cpu_idle_acpi(sbintime_t sbt)
 {
 	int *state;
 
 	state = (int *)PCPU_PTR(monitorbuf);
 	*state = STATE_SLEEPING;
 
 	/* See comments in cpu_idle_hlt(). */
 	disable_intr();
 	if (sched_runnable())
 		enable_intr();
 	else if (cpu_idle_hook)
 		cpu_idle_hook(sbt);
 	else
 		__asm __volatile("sti; hlt");
 	*state = STATE_RUNNING;
 }
 
 static void
 cpu_idle_hlt(sbintime_t sbt)
 {
 	int *state;
 
 	state = (int *)PCPU_PTR(monitorbuf);
 	*state = STATE_SLEEPING;
 
 	/*
 	 * Since we may be in a critical section from cpu_idle(), if
 	 * an interrupt fires during that critical section we may have
 	 * a pending preemption.  If the CPU halts, then that thread
 	 * may not execute until a later interrupt awakens the CPU.
 	 * To handle this race, check for a runnable thread after
 	 * disabling interrupts and immediately return if one is
 	 * found.  Also, we must absolutely guarentee that hlt is
 	 * the next instruction after sti.  This ensures that any
 	 * interrupt that fires after the call to disable_intr() will
 	 * immediately awaken the CPU from hlt.  Finally, please note
 	 * that on x86 this works fine because of interrupts enabled only
 	 * after the instruction following sti takes place, while IF is set
 	 * to 1 immediately, allowing hlt instruction to acknowledge the
 	 * interrupt.
 	 */
 	disable_intr();
 	if (sched_runnable())
 		enable_intr();
 	else
 		__asm __volatile("sti; hlt");
 	*state = STATE_RUNNING;
 }
 
 static void
 cpu_idle_mwait(sbintime_t sbt)
 {
 	int *state;
 
 	state = (int *)PCPU_PTR(monitorbuf);
 	*state = STATE_MWAIT;
 
 	/* See comments in cpu_idle_hlt(). */
 	disable_intr();
 	if (sched_runnable()) {
 		enable_intr();
 		*state = STATE_RUNNING;
 		return;
 	}
 	cpu_monitor(state, 0, 0);
 	if (*state == STATE_MWAIT)
 		__asm __volatile("sti; mwait" : : "a" (MWAIT_C1), "c" (0));
 	else
 		enable_intr();
 	*state = STATE_RUNNING;
 }
 
 static void
 cpu_idle_spin(sbintime_t sbt)
 {
 	int *state;
 	int i;
 
 	state = (int *)PCPU_PTR(monitorbuf);
 	*state = STATE_RUNNING;
 
 	/*
 	 * The sched_runnable() call is racy but as long as there is
 	 * a loop missing it one time will have just a little impact if any
 	 * (and it is much better than missing the check at all).
 	 */
 	for (i = 0; i < 1000; i++) {
 		if (sched_runnable())
 			return;
 		cpu_spinwait();
 	}
 }
 
 /*
  * C1E renders the local APIC timer dead, so we disable it by
  * reading the Interrupt Pending Message register and clearing
  * both C1eOnCmpHalt (bit 28) and SmiOnCmpHalt (bit 27).
  * 
  * Reference:
  *   "BIOS and Kernel Developer's Guide for AMD NPT Family 0Fh Processors"
  *   #32559 revision 3.00+
  */
 #define	MSR_AMDK8_IPM		0xc0010055
 #define	AMDK8_SMIONCMPHALT	(1ULL << 27)
 #define	AMDK8_C1EONCMPHALT	(1ULL << 28)
 #define	AMDK8_CMPHALT		(AMDK8_SMIONCMPHALT | AMDK8_C1EONCMPHALT)
 
 static void
 cpu_probe_amdc1e(void)
 {
 
 	/*
 	 * Detect the presence of C1E capability mostly on latest
 	 * dual-cores (or future) k8 family.
 	 */
 	if (cpu_vendor_id == CPU_VENDOR_AMD &&
 	    (cpu_id & 0x00000f00) == 0x00000f00 &&
 	    (cpu_id & 0x0fff0000) >=  0x00040000) {
 		cpu_ident_amdc1e = 1;
 	}
 }
 
 void (*cpu_idle_fn)(sbintime_t) = cpu_idle_acpi;
 
 void
 cpu_idle(int busy)
 {
 	uint64_t msr;
 	sbintime_t sbt = -1;
 
 	CTR2(KTR_SPARE2, "cpu_idle(%d) at %d",
 	    busy, curcpu);
 #ifdef MP_WATCHDOG
 	ap_watchdog(PCPU_GET(cpuid));
 #endif
 	/* If we are busy - try to use fast methods. */
 	if (busy) {
 		if ((cpu_feature2 & CPUID2_MON) && idle_mwait) {
 			cpu_idle_mwait(busy);
 			goto out;
 		}
 	}
 
 	/* If we have time - switch timers into idle mode. */
 	if (!busy) {
 		critical_enter();
 		sbt = cpu_idleclock();
 	}
 
 	/* Apply AMD APIC timer C1E workaround. */
 	if (cpu_ident_amdc1e && cpu_disable_c3_sleep) {
 		msr = rdmsr(MSR_AMDK8_IPM);
 		if (msr & AMDK8_CMPHALT)
 			wrmsr(MSR_AMDK8_IPM, msr & ~AMDK8_CMPHALT);
 	}
 
 	/* Call main idle method. */
 	cpu_idle_fn(sbt);
 
 	/* Switch timers mack into active mode. */
 	if (!busy) {
 		cpu_activeclock();
 		critical_exit();
 	}
 out:
 	CTR2(KTR_SPARE2, "cpu_idle(%d) at %d done",
 	    busy, curcpu);
 }
 
 int
 cpu_idle_wakeup(int cpu)
 {
 	struct pcpu *pcpu;
 	int *state;
 
 	pcpu = pcpu_find(cpu);
 	state = (int *)pcpu->pc_monitorbuf;
 	/*
 	 * This doesn't need to be atomic since missing the race will
 	 * simply result in unnecessary IPIs.
 	 */
 	if (*state == STATE_SLEEPING)
 		return (0);
 	if (*state == STATE_MWAIT)
 		*state = STATE_RUNNING;
 	return (1);
 }
 
 /*
  * Ordered by speed/power consumption.
  */
 struct {
 	void	*id_fn;
 	char	*id_name;
 } idle_tbl[] = {
 	{ cpu_idle_spin, "spin" },
 	{ cpu_idle_mwait, "mwait" },
 	{ cpu_idle_hlt, "hlt" },
 	{ cpu_idle_acpi, "acpi" },
 	{ NULL, NULL }
 };
 
 static int
 idle_sysctl_available(SYSCTL_HANDLER_ARGS)
 {
 	char *avail, *p;
 	int error;
 	int i;
 
 	avail = malloc(256, M_TEMP, M_WAITOK);
 	p = avail;
 	for (i = 0; idle_tbl[i].id_name != NULL; i++) {
 		if (strstr(idle_tbl[i].id_name, "mwait") &&
 		    (cpu_feature2 & CPUID2_MON) == 0)
 			continue;
 		if (strcmp(idle_tbl[i].id_name, "acpi") == 0 &&
 		    cpu_idle_hook == NULL)
 			continue;
 		p += sprintf(p, "%s%s", p != avail ? ", " : "",
 		    idle_tbl[i].id_name);
 	}
 	error = sysctl_handle_string(oidp, avail, 0, req);
 	free(avail, M_TEMP);
 	return (error);
 }
 
 SYSCTL_PROC(_machdep, OID_AUTO, idle_available, CTLTYPE_STRING | CTLFLAG_RD,
     0, 0, idle_sysctl_available, "A", "list of available idle functions");
 
 static int
 idle_sysctl(SYSCTL_HANDLER_ARGS)
 {
 	char buf[16];
 	int error;
 	char *p;
 	int i;
 
 	p = "unknown";
 	for (i = 0; idle_tbl[i].id_name != NULL; i++) {
 		if (idle_tbl[i].id_fn == cpu_idle_fn) {
 			p = idle_tbl[i].id_name;
 			break;
 		}
 	}
 	strncpy(buf, p, sizeof(buf));
 	error = sysctl_handle_string(oidp, buf, sizeof(buf), req);
 	if (error != 0 || req->newptr == NULL)
 		return (error);
 	for (i = 0; idle_tbl[i].id_name != NULL; i++) {
 		if (strstr(idle_tbl[i].id_name, "mwait") &&
 		    (cpu_feature2 & CPUID2_MON) == 0)
 			continue;
 		if (strcmp(idle_tbl[i].id_name, "acpi") == 0 &&
 		    cpu_idle_hook == NULL)
 			continue;
 		if (strcmp(idle_tbl[i].id_name, buf))
 			continue;
 		cpu_idle_fn = idle_tbl[i].id_fn;
 		return (0);
 	}
 	return (EINVAL);
 }
 
 SYSCTL_PROC(_machdep, OID_AUTO, idle, CTLTYPE_STRING | CTLFLAG_RW, 0, 0,
     idle_sysctl, "A", "currently selected idle function");
 
 /*
  * Reset registers to default values on exec.
  */
 void
 exec_setregs(struct thread *td, struct image_params *imgp, u_long stack)
 {
 	struct trapframe *regs = td->td_frame;
 	struct pcb *pcb = td->td_pcb;
 
 	mtx_lock(&dt_lock);
 	if (td->td_proc->p_md.md_ldt != NULL)
 		user_ldt_free(td);
 	else
 		mtx_unlock(&dt_lock);
 	
 	pcb->pcb_fsbase = 0;
 	pcb->pcb_gsbase = 0;
 	clear_pcb_flags(pcb, PCB_32BIT);
 	pcb->pcb_initial_fpucw = __INITIAL_FPUCW__;
 	set_pcb_flags(pcb, PCB_FULL_IRET);
 
 	bzero((char *)regs, sizeof(struct trapframe));
 	regs->tf_rip = imgp->entry_addr;
 	regs->tf_rsp = ((stack - 8) & ~0xFul) + 8;
 	regs->tf_rdi = stack;		/* argv */
 	regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
 	regs->tf_ss = _udatasel;
 	regs->tf_cs = _ucodesel;
 	regs->tf_ds = _udatasel;
 	regs->tf_es = _udatasel;
 	regs->tf_fs = _ufssel;
 	regs->tf_gs = _ugssel;
 	regs->tf_flags = TF_HASSEGS;
 	td->td_retval[1] = 0;
 
 	/*
 	 * Reset the hardware debug registers if they were in use.
 	 * They won't have any meaning for the newly exec'd process.
 	 */
 	if (pcb->pcb_flags & PCB_DBREGS) {
 		pcb->pcb_dr0 = 0;
 		pcb->pcb_dr1 = 0;
 		pcb->pcb_dr2 = 0;
 		pcb->pcb_dr3 = 0;
 		pcb->pcb_dr6 = 0;
 		pcb->pcb_dr7 = 0;
 		if (pcb == curpcb) {
 			/*
 			 * Clear the debug registers on the running
 			 * CPU, otherwise they will end up affecting
 			 * the next process we switch to.
 			 */
 			reset_dbregs();
 		}
 		clear_pcb_flags(pcb, PCB_DBREGS);
 	}
 
 	/*
 	 * Drop the FP state if we hold it, so that the process gets a
 	 * clean FP state if it uses the FPU again.
 	 */
 	fpstate_drop(td);
 }
 
 void
 cpu_setregs(void)
 {
 	register_t cr0;
 
 	cr0 = rcr0();
 	/*
 	 * CR0_MP, CR0_NE and CR0_TS are also set by npx_probe() for the
 	 * BSP.  See the comments there about why we set them.
 	 */
 	cr0 |= CR0_MP | CR0_NE | CR0_TS | CR0_WP | CR0_AM;
 	load_cr0(cr0);
 }
 
 /*
  * Initialize amd64 and configure to run kernel
  */
 
 /*
  * Initialize segments & interrupt table
  */
 
 struct user_segment_descriptor gdt[NGDT * MAXCPU];/* global descriptor tables */
 static struct gate_descriptor idt0[NIDT];
 struct gate_descriptor *idt = &idt0[0];	/* interrupt descriptor table */
 
 static char dblfault_stack[PAGE_SIZE] __aligned(16);
 
 static char nmi0_stack[PAGE_SIZE] __aligned(16);
 CTASSERT(sizeof(struct nmi_pcpu) == 16);
 
 struct amd64tss common_tss[MAXCPU];
 
 /*
  * Software prototypes -- in more palatable form.
  *
  * Keep GUFS32, GUGS32, GUCODE32 and GUDATA at the same
  * slots as corresponding segments for i386 kernel.
  */
 struct soft_segment_descriptor gdt_segs[] = {
 /* GNULL_SEL	0 Null Descriptor */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0x0,
 	.ssd_type = 0,
 	.ssd_dpl = 0,
 	.ssd_p = 0,
 	.ssd_long = 0,
 	.ssd_def32 = 0,
 	.ssd_gran = 0		},
 /* GNULL2_SEL	1 Null Descriptor */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0x0,
 	.ssd_type = 0,
 	.ssd_dpl = 0,
 	.ssd_p = 0,
 	.ssd_long = 0,
 	.ssd_def32 = 0,
 	.ssd_gran = 0		},
 /* GUFS32_SEL	2 32 bit %gs Descriptor for user */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0xfffff,
 	.ssd_type = SDT_MEMRWA,
 	.ssd_dpl = SEL_UPL,
 	.ssd_p = 1,
 	.ssd_long = 0,
 	.ssd_def32 = 1,
 	.ssd_gran = 1		},
 /* GUGS32_SEL	3 32 bit %fs Descriptor for user */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0xfffff,
 	.ssd_type = SDT_MEMRWA,
 	.ssd_dpl = SEL_UPL,
 	.ssd_p = 1,
 	.ssd_long = 0,
 	.ssd_def32 = 1,
 	.ssd_gran = 1		},
 /* GCODE_SEL	4 Code Descriptor for kernel */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0xfffff,
 	.ssd_type = SDT_MEMERA,
 	.ssd_dpl = SEL_KPL,
 	.ssd_p = 1,
 	.ssd_long = 1,
 	.ssd_def32 = 0,
 	.ssd_gran = 1		},
 /* GDATA_SEL	5 Data Descriptor for kernel */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0xfffff,
 	.ssd_type = SDT_MEMRWA,
 	.ssd_dpl = SEL_KPL,
 	.ssd_p = 1,
 	.ssd_long = 1,
 	.ssd_def32 = 0,
 	.ssd_gran = 1		},
 /* GUCODE32_SEL	6 32 bit Code Descriptor for user */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0xfffff,
 	.ssd_type = SDT_MEMERA,
 	.ssd_dpl = SEL_UPL,
 	.ssd_p = 1,
 	.ssd_long = 0,
 	.ssd_def32 = 1,
 	.ssd_gran = 1		},
 /* GUDATA_SEL	7 32/64 bit Data Descriptor for user */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0xfffff,
 	.ssd_type = SDT_MEMRWA,
 	.ssd_dpl = SEL_UPL,
 	.ssd_p = 1,
 	.ssd_long = 0,
 	.ssd_def32 = 1,
 	.ssd_gran = 1		},
 /* GUCODE_SEL	8 64 bit Code Descriptor for user */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0xfffff,
 	.ssd_type = SDT_MEMERA,
 	.ssd_dpl = SEL_UPL,
 	.ssd_p = 1,
 	.ssd_long = 1,
 	.ssd_def32 = 0,
 	.ssd_gran = 1		},
 /* GPROC0_SEL	9 Proc 0 Tss Descriptor */
 {	.ssd_base = 0x0,
 	.ssd_limit = sizeof(struct amd64tss) + IOPAGES * PAGE_SIZE - 1,
 	.ssd_type = SDT_SYSTSS,
 	.ssd_dpl = SEL_KPL,
 	.ssd_p = 1,
 	.ssd_long = 0,
 	.ssd_def32 = 0,
 	.ssd_gran = 0		},
 /* Actually, the TSS is a system descriptor which is double size */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0x0,
 	.ssd_type = 0,
 	.ssd_dpl = 0,
 	.ssd_p = 0,
 	.ssd_long = 0,
 	.ssd_def32 = 0,
 	.ssd_gran = 0		},
 /* GUSERLDT_SEL	11 LDT Descriptor */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0x0,
 	.ssd_type = 0,
 	.ssd_dpl = 0,
 	.ssd_p = 0,
 	.ssd_long = 0,
 	.ssd_def32 = 0,
 	.ssd_gran = 0		},
 /* GUSERLDT_SEL	12 LDT Descriptor, double size */
 {	.ssd_base = 0x0,
 	.ssd_limit = 0x0,
 	.ssd_type = 0,
 	.ssd_dpl = 0,
 	.ssd_p = 0,
 	.ssd_long = 0,
 	.ssd_def32 = 0,
 	.ssd_gran = 0		},
 };
 
 void
 setidt(int idx, inthand_t *func, int typ, int dpl, int ist)
 {
 	struct gate_descriptor *ip;
 
 	ip = idt + idx;
 	ip->gd_looffset = (uintptr_t)func;
 	ip->gd_selector = GSEL(GCODE_SEL, SEL_KPL);
 	ip->gd_ist = ist;
 	ip->gd_xx = 0;
 	ip->gd_type = typ;
 	ip->gd_dpl = dpl;
 	ip->gd_p = 1;
 	ip->gd_hioffset = ((uintptr_t)func)>>16 ;
 }
 
 extern inthand_t
 	IDTVEC(div), IDTVEC(dbg), IDTVEC(nmi), IDTVEC(bpt), IDTVEC(ofl),
 	IDTVEC(bnd), IDTVEC(ill), IDTVEC(dna), IDTVEC(fpusegm),
 	IDTVEC(tss), IDTVEC(missing), IDTVEC(stk), IDTVEC(prot),
 	IDTVEC(page), IDTVEC(mchk), IDTVEC(rsvd), IDTVEC(fpu), IDTVEC(align),
 	IDTVEC(xmm), IDTVEC(dblfault),
 #ifdef KDTRACE_HOOKS
 	IDTVEC(dtrace_ret),
 #endif
 #ifdef XENHVM
 	IDTVEC(xen_intr_upcall),
 #endif
 	IDTVEC(fast_syscall), IDTVEC(fast_syscall32);
 
 #ifdef DDB
 /*
  * Display the index and function name of any IDT entries that don't use
  * the default 'rsvd' entry point.
  */
 DB_SHOW_COMMAND(idt, db_show_idt)
 {
 	struct gate_descriptor *ip;
 	int idx;
 	uintptr_t func;
 
 	ip = idt;
 	for (idx = 0; idx < NIDT && !db_pager_quit; idx++) {
 		func = ((long)ip->gd_hioffset << 16 | ip->gd_looffset);
 		if (func != (uintptr_t)&IDTVEC(rsvd)) {
 			db_printf("%3d\t", idx);
 			db_printsym(func, DB_STGY_PROC);
 			db_printf("\n");
 		}
 		ip++;
 	}
 }
 
 /* Show privileged registers. */
 DB_SHOW_COMMAND(sysregs, db_show_sysregs)
 {
 	struct {
 		uint16_t limit;
 		uint64_t base;
 	} __packed idtr, gdtr;
 	uint16_t ldt, tr;
 
 	__asm __volatile("sidt %0" : "=m" (idtr));
 	db_printf("idtr\t0x%016lx/%04x\n",
 	    (u_long)idtr.base, (u_int)idtr.limit);
 	__asm __volatile("sgdt %0" : "=m" (gdtr));
 	db_printf("gdtr\t0x%016lx/%04x\n",
 	    (u_long)gdtr.base, (u_int)gdtr.limit);
 	__asm __volatile("sldt %0" : "=r" (ldt));
 	db_printf("ldtr\t0x%04x\n", ldt);
 	__asm __volatile("str %0" : "=r" (tr));
 	db_printf("tr\t0x%04x\n", tr);
 	db_printf("cr0\t0x%016lx\n", rcr0());
 	db_printf("cr2\t0x%016lx\n", rcr2());
 	db_printf("cr3\t0x%016lx\n", rcr3());
 	db_printf("cr4\t0x%016lx\n", rcr4());
 	if (rcr4() & CR4_XSAVE)
 		db_printf("xcr0\t0x%016lx\n", rxcr(0));
 	db_printf("EFER\t0x%016lx\n", rdmsr(MSR_EFER));
 	if (cpu_feature2 & (CPUID2_VMX | CPUID2_SMX))
 		db_printf("FEATURES_CTL\t%016lx\n",
 		    rdmsr(MSR_IA32_FEATURE_CONTROL));
 	db_printf("DEBUG_CTL\t0x%016lx\n", rdmsr(MSR_DEBUGCTLMSR));
 	db_printf("PAT\t0x%016lx\n", rdmsr(MSR_PAT));
 	db_printf("GSBASE\t0x%016lx\n", rdmsr(MSR_GSBASE));
 }
 
 DB_SHOW_COMMAND(dbregs, db_show_dbregs)
 {
 
 	db_printf("dr0\t0x%016lx\n", rdr0());
 	db_printf("dr1\t0x%016lx\n", rdr1());
 	db_printf("dr2\t0x%016lx\n", rdr2());
 	db_printf("dr3\t0x%016lx\n", rdr3());
 	db_printf("dr6\t0x%016lx\n", rdr6());
 	db_printf("dr7\t0x%016lx\n", rdr7());	
 }
 #endif
 
 void
 sdtossd(sd, ssd)
 	struct user_segment_descriptor *sd;
 	struct soft_segment_descriptor *ssd;
 {
 
 	ssd->ssd_base  = (sd->sd_hibase << 24) | sd->sd_lobase;
 	ssd->ssd_limit = (sd->sd_hilimit << 16) | sd->sd_lolimit;
 	ssd->ssd_type  = sd->sd_type;
 	ssd->ssd_dpl   = sd->sd_dpl;
 	ssd->ssd_p     = sd->sd_p;
 	ssd->ssd_long  = sd->sd_long;
 	ssd->ssd_def32 = sd->sd_def32;
 	ssd->ssd_gran  = sd->sd_gran;
 }
 
 void
 ssdtosd(ssd, sd)
 	struct soft_segment_descriptor *ssd;
 	struct user_segment_descriptor *sd;
 {
 
 	sd->sd_lobase = (ssd->ssd_base) & 0xffffff;
 	sd->sd_hibase = (ssd->ssd_base >> 24) & 0xff;
 	sd->sd_lolimit = (ssd->ssd_limit) & 0xffff;
 	sd->sd_hilimit = (ssd->ssd_limit >> 16) & 0xf;
 	sd->sd_type  = ssd->ssd_type;
 	sd->sd_dpl   = ssd->ssd_dpl;
 	sd->sd_p     = ssd->ssd_p;
 	sd->sd_long  = ssd->ssd_long;
 	sd->sd_def32 = ssd->ssd_def32;
 	sd->sd_gran  = ssd->ssd_gran;
 }
 
 void
 ssdtosyssd(ssd, sd)
 	struct soft_segment_descriptor *ssd;
 	struct system_segment_descriptor *sd;
 {
 
 	sd->sd_lobase = (ssd->ssd_base) & 0xffffff;
 	sd->sd_hibase = (ssd->ssd_base >> 24) & 0xfffffffffful;
 	sd->sd_lolimit = (ssd->ssd_limit) & 0xffff;
 	sd->sd_hilimit = (ssd->ssd_limit >> 16) & 0xf;
 	sd->sd_type  = ssd->ssd_type;
 	sd->sd_dpl   = ssd->ssd_dpl;
 	sd->sd_p     = ssd->ssd_p;
 	sd->sd_gran  = ssd->ssd_gran;
 }
 
 #if !defined(DEV_ATPIC) && defined(DEV_ISA)
 #include <isa/isavar.h>
 #include <isa/isareg.h>
 /*
  * Return a bitmap of the current interrupt requests.  This is 8259-specific
  * and is only suitable for use at probe time.
  * This is only here to pacify sio.  It is NOT FATAL if this doesn't work.
  * It shouldn't be here.  There should probably be an APIC centric
  * implementation in the apic driver code, if at all.
  */
 intrmask_t
 isa_irq_pending(void)
 {
 	u_char irr1;
 	u_char irr2;
 
 	irr1 = inb(IO_ICU1);
 	irr2 = inb(IO_ICU2);
 	return ((irr2 << 8) | irr1);
 }
 #endif
 
 u_int basemem;
 
 static int
 add_physmap_entry(uint64_t base, uint64_t length, vm_paddr_t *physmap,
     int *physmap_idxp)
 {
 	int i, insert_idx, physmap_idx;
 
 	physmap_idx = *physmap_idxp;
 
 	if (length == 0)
 		return (1);
 
 	/*
 	 * Find insertion point while checking for overlap.  Start off by
 	 * assuming the new entry will be added to the end.
+	 *
+	 * NB: physmap_idx points to the next free slot.
 	 */
-	insert_idx = physmap_idx + 2;
+	insert_idx = physmap_idx;
 	for (i = 0; i <= physmap_idx; i += 2) {
 		if (base < physmap[i + 1]) {
 			if (base + length <= physmap[i]) {
 				insert_idx = i;
 				break;
 			}
 			if (boothowto & RB_VERBOSE)
 				printf(
 		    "Overlapping memory regions, ignoring second region\n");
 			return (1);
 		}
 	}
 
 	/* See if we can prepend to the next entry. */
 	if (insert_idx <= physmap_idx && base + length == physmap[insert_idx]) {
 		physmap[insert_idx] = base;
 		return (1);
 	}
 
 	/* See if we can append to the previous entry. */
 	if (insert_idx > 0 && base == physmap[insert_idx - 1]) {
 		physmap[insert_idx - 1] += length;
 		return (1);
 	}
 
 	physmap_idx += 2;
 	*physmap_idxp = physmap_idx;
 	if (physmap_idx == PHYSMAP_SIZE) {
 		printf(
 		"Too many segments in the physical address map, giving up\n");
 		return (0);
 	}
 
 	/*
 	 * Move the last 'N' entries down to make room for the new
 	 * entry if needed.
 	 */
-	for (i = physmap_idx; i > insert_idx; i -= 2) {
+	for (i = (physmap_idx - 2); i > insert_idx; i -= 2) {
 		physmap[i] = physmap[i - 2];
 		physmap[i + 1] = physmap[i - 1];
 	}
 
 	/* Insert the new entry. */
 	physmap[insert_idx] = base;
 	physmap[insert_idx + 1] = base + length;
 	return (1);
 }
 
 static void
 add_smap_entries(struct bios_smap *smapbase, vm_paddr_t *physmap,
     int *physmap_idx)
 {
 	struct bios_smap *smap, *smapend;
 	u_int32_t smapsize;
 
 	/*
 	 * Memory map from INT 15:E820.
 	 *
 	 * subr_module.c says:
 	 * "Consumer may safely assume that size value precedes data."
 	 * ie: an int32_t immediately precedes smap.
 	 */
 	smapsize = *((u_int32_t *)smapbase - 1);
 	smapend = (struct bios_smap *)((uintptr_t)smapbase + smapsize);
 
 	for (smap = smapbase; smap < smapend; smap++) {
 		if (boothowto & RB_VERBOSE)
 			printf("SMAP type=%02x base=%016lx len=%016lx\n",
 			    smap->type, smap->base, smap->length);
 
 		if (smap->type != SMAP_TYPE_MEMORY)
 			continue;
 
 		if (!add_physmap_entry(smap->base, smap->length, physmap,
 		    physmap_idx))
 			break;
 	}
 }
 
 #define efi_next_descriptor(ptr, size) \
 	((struct efi_md *)(((uint8_t *) ptr) + size))
 
 static void
 add_efi_map_entries(struct efi_map_header *efihdr, vm_paddr_t *physmap,
     int *physmap_idx)
 {
 	struct efi_md *map, *p;
 	const char *type;
 	size_t efisz;
 	int ndesc, i;
 
 	static const char *types[] = {
 		"Reserved",
 		"LoaderCode",
 		"LoaderData",
 		"BootServicesCode",
 		"BootServicesData",
 		"RuntimeServicesCode",
 		"RuntimeServicesData",
 		"ConventionalMemory",
 		"UnusableMemory",
 		"ACPIReclaimMemory",
 		"ACPIMemoryNVS",
 		"MemoryMappedIO",
 		"MemoryMappedIOPortSpace",
 		"PalCode"
 	};
 
 	/*
 	 * Memory map data provided by UEFI via the GetMemoryMap
 	 * Boot Services API.
 	 */
 	efisz = (sizeof(struct efi_map_header) + 0xf) & ~0xf;
 	map = (struct efi_md *)((uint8_t *)efihdr + efisz); 
 
 	if (efihdr->descriptor_size == 0)
 		return;
 	ndesc = efihdr->memory_size / efihdr->descriptor_size;
 
 	if (boothowto & RB_VERBOSE)
 		printf("%23s %12s %12s %8s %4s\n",
 		    "Type", "Physical", "Virtual", "#Pages", "Attr");
 
 	for (i = 0, p = map; i < ndesc; i++,
 	    p = efi_next_descriptor(p, efihdr->descriptor_size)) {
 		if (boothowto & RB_VERBOSE) {
 			if (p->md_type <= EFI_MD_TYPE_PALCODE)
 				type = types[p->md_type];
 			else
 				type = "<INVALID>";
 			printf("%23s %012lx %12p %08lx ", type, p->md_phys,
 			    p->md_virt, p->md_pages);
 			if (p->md_attr & EFI_MD_ATTR_UC)
 				printf("UC ");
 			if (p->md_attr & EFI_MD_ATTR_WC)
 				printf("WC ");
 			if (p->md_attr & EFI_MD_ATTR_WT)
 				printf("WT ");
 			if (p->md_attr & EFI_MD_ATTR_WB)
 				printf("WB ");
 			if (p->md_attr & EFI_MD_ATTR_UCE)
 				printf("UCE ");
 			if (p->md_attr & EFI_MD_ATTR_WP)
 				printf("WP ");
 			if (p->md_attr & EFI_MD_ATTR_RP)
 				printf("RP ");
 			if (p->md_attr & EFI_MD_ATTR_XP)
 				printf("XP ");
 			if (p->md_attr & EFI_MD_ATTR_RT)
 				printf("RUNTIME");
 			printf("\n");
 		}
 
 		switch (p->md_type) {
 		case EFI_MD_TYPE_CODE:
 		case EFI_MD_TYPE_DATA:
 		case EFI_MD_TYPE_BS_CODE:
 		case EFI_MD_TYPE_BS_DATA:
 		case EFI_MD_TYPE_FREE:
 			/*
 			 * We're allowed to use any entry with these types.
 			 */
 			break;
 		default:
 			continue;
 		}
 
 		if (!add_physmap_entry(p->md_phys, (p->md_pages * PAGE_SIZE),
 		    physmap, physmap_idx))
 			break;
 	}
 }
 
 static char bootmethod[16] = "";
 SYSCTL_STRING(_machdep, OID_AUTO, bootmethod, CTLFLAG_RD, bootmethod, 0,
     "System firmware boot method");
 
 #define	PAGES_PER_GB	(1024 * 1024 * 1024 / PAGE_SIZE)
 
 /*
  * Populate the (physmap) array with base/bound pairs describing the
  * available physical memory in the system, then test this memory and
  * build the phys_avail array describing the actually-available memory.
  *
  * Total memory size may be set by the kernel environment variable
  * hw.physmem or the compile-time define MAXMEM.
  *
  * XXX first should be vm_paddr_t.
  */
 static void
 getmemsize(caddr_t kmdp, u_int64_t first)
 {
 	int i, physmap_idx, pa_indx, da_indx;
 	vm_paddr_t pa, physmap[PHYSMAP_SIZE];
 	u_long physmem_start, physmem_tunable, memtest;
 	pt_entry_t *pte;
 	struct bios_smap *smapbase;
 	struct efi_map_header *efihdr;
 	quad_t dcons_addr, dcons_size;
 	int page_counter;
 
 	bzero(physmap, sizeof(physmap));
-	basemem = 0;
 	physmap_idx = 0;
 
 	efihdr = (struct efi_map_header *)preload_search_info(kmdp,
 	    MODINFO_METADATA | MODINFOMD_EFI_MAP);
 	smapbase = (struct bios_smap *)preload_search_info(kmdp,
 	    MODINFO_METADATA | MODINFOMD_SMAP);
 
 	if (efihdr != NULL) {
 		add_efi_map_entries(efihdr, physmap, &physmap_idx);
 		strlcpy(bootmethod, "UEFI", sizeof(bootmethod));
 	} else if (smapbase != NULL) {
 		add_smap_entries(smapbase, physmap, &physmap_idx);
 		strlcpy(bootmethod, "BIOS", sizeof(bootmethod));
 	} else {
 		panic("No BIOS smap or EFI map info from loader!");
 	}
 
+	physmap_idx -= 2;
+
 	/*
 	 * Find the 'base memory' segment for SMP
 	 */
 	basemem = 0;
 	for (i = 0; i <= physmap_idx; i += 2) {
-		if (physmap[i] == 0x00000000) {
+		if (physmap[i] <= 0xA0000) {
 			basemem = physmap[i + 1] / 1024;
 			break;
 		}
 	}
-	if (basemem == 0)
-		panic("BIOS smap did not include a basemem segment!");
+	if (basemem == 0 || basemem > 640) {
+		if (bootverbose)
+			printf(
+		"Memory map doesn't contain a basemem segment, faking it");
+		basemem = 640;
+	}
 
 #ifdef SMP
 	/* make hole for AP bootstrap code */
+	if (physmap[1] >= 0x100000000)
+		panic("Basemem segment is not suitable for AP bootstrap code!");
 	physmap[1] = mp_bootaddress(physmap[1] / 1024);
 #endif
 
 	/*
 	 * Maxmem isn't the "maximum memory", it's one larger than the
 	 * highest page of the physical address space.  It should be
 	 * called something like "Maxphyspage".  We may adjust this
 	 * based on ``hw.physmem'' and the results of the memory test.
 	 */
 	Maxmem = atop(physmap[physmap_idx + 1]);
 
 #ifdef MAXMEM
 	Maxmem = MAXMEM / 4;
 #endif
 
 	if (TUNABLE_ULONG_FETCH("hw.physmem", &physmem_tunable))
 		Maxmem = atop(physmem_tunable);
 
 	/*
 	 * The boot memory test is disabled by default, as it takes a
 	 * significant amount of time on large-memory systems, and is
 	 * unfriendly to virtual machines as it unnecessarily touches all
 	 * pages.
 	 *
 	 * A general name is used as the code may be extended to support
 	 * additional tests beyond the current "page present" test.
 	 */
 	memtest = 0;
 	TUNABLE_ULONG_FETCH("hw.memtest.tests", &memtest);
 
 	/*
 	 * Don't allow MAXMEM or hw.physmem to extend the amount of memory
 	 * in the system.
 	 */
 	if (Maxmem > atop(physmap[physmap_idx + 1]))
 		Maxmem = atop(physmap[physmap_idx + 1]);
 
 	if (atop(physmap[physmap_idx + 1]) != Maxmem &&
 	    (boothowto & RB_VERBOSE))
 		printf("Physical memory use set to %ldK\n", Maxmem * 4);
 
 	/* call pmap initialization to make new kernel address space */
 	pmap_bootstrap(&first);
 
 	/*
 	 * Size up each available chunk of physical memory.
 	 *
 	 * XXX Some BIOSes corrupt low 64KB between suspend and resume.
 	 * By default, mask off the first 16 pages unless we appear to be
 	 * running in a VM.
 	 */
 	physmem_start = (vm_guest > VM_GUEST_NO ? 1 : 16) << PAGE_SHIFT;
 	TUNABLE_ULONG_FETCH("hw.physmem.start", &physmem_start);
-	if (physmem_start < PAGE_SIZE)
-		physmap[0] = PAGE_SIZE;
-	else if (physmem_start >= physmap[1])
-		physmap[0] = round_page(physmap[1] - PAGE_SIZE);
-	else
-		physmap[0] = round_page(physmem_start);
+	if (physmap[0] < physmem_start) {
+		if (physmem_start < PAGE_SIZE)
+			physmap[0] = PAGE_SIZE;
+		else if (physmem_start >= physmap[1])
+			physmap[0] = round_page(physmap[1] - PAGE_SIZE);
+		else
+			physmap[0] = round_page(physmem_start);
+	}
 	pa_indx = 0;
 	da_indx = 1;
 	phys_avail[pa_indx++] = physmap[0];
 	phys_avail[pa_indx] = physmap[0];
 	dump_avail[da_indx] = physmap[0];
 	pte = CMAP1;
 
 	/*
 	 * Get dcons buffer address
 	 */
 	if (getenv_quad("dcons.addr", &dcons_addr) == 0 ||
 	    getenv_quad("dcons.size", &dcons_size) == 0)
 		dcons_addr = 0;
 
 	/*
 	 * physmap is in bytes, so when converting to page boundaries,
 	 * round up the start address and round down the end address.
 	 */
 	page_counter = 0;
 	if (memtest != 0)
 		printf("Testing system memory");
 	for (i = 0; i <= physmap_idx; i += 2) {
 		vm_paddr_t end;
 
 		end = ptoa((vm_paddr_t)Maxmem);
 		if (physmap[i + 1] < end)
 			end = trunc_page(physmap[i + 1]);
 		for (pa = round_page(physmap[i]); pa < end; pa += PAGE_SIZE) {
 			int tmp, page_bad, full;
 			int *ptr = (int *)CADDR1;
 
 			full = FALSE;
 			/*
 			 * block out kernel memory as not available.
 			 */
 			if (pa >= (vm_paddr_t)kernphys && pa < first)
 				goto do_dump_avail;
 
 			/*
 			 * block out dcons buffer
 			 */
 			if (dcons_addr > 0
 			    && pa >= trunc_page(dcons_addr)
 			    && pa < dcons_addr + dcons_size)
 				goto do_dump_avail;
 
 			page_bad = FALSE;
 			if (memtest == 0)
 				goto skip_memtest;
 
 			/*
 			 * Print a "." every GB to show we're making
 			 * progress.
 			 */
 			page_counter++;
 			if ((page_counter % PAGES_PER_GB) == 0)
 				printf(".");
 
 			/*
 			 * map page into kernel: valid, read/write,non-cacheable
 			 */
 			*pte = pa | PG_V | PG_RW | PG_NC_PWT | PG_NC_PCD;
 			invltlb();
 
 			tmp = *(int *)ptr;
 			/*
 			 * Test for alternating 1's and 0's
 			 */
 			*(volatile int *)ptr = 0xaaaaaaaa;
 			if (*(volatile int *)ptr != 0xaaaaaaaa)
 				page_bad = TRUE;
 			/*
 			 * Test for alternating 0's and 1's
 			 */
 			*(volatile int *)ptr = 0x55555555;
 			if (*(volatile int *)ptr != 0x55555555)
 				page_bad = TRUE;
 			/*
 			 * Test for all 1's
 			 */
 			*(volatile int *)ptr = 0xffffffff;
 			if (*(volatile int *)ptr != 0xffffffff)
 				page_bad = TRUE;
 			/*
 			 * Test for all 0's
 			 */
 			*(volatile int *)ptr = 0x0;
 			if (*(volatile int *)ptr != 0x0)
 				page_bad = TRUE;
 			/*
 			 * Restore original value.
 			 */
 			*(int *)ptr = tmp;
 
 skip_memtest:
 			/*
 			 * Adjust array of valid/good pages.
 			 */
 			if (page_bad == TRUE)
 				continue;
 			/*
 			 * If this good page is a continuation of the
 			 * previous set of good pages, then just increase
 			 * the end pointer. Otherwise start a new chunk.
 			 * Note that "end" points one higher than end,
 			 * making the range >= start and < end.
 			 * If we're also doing a speculative memory
 			 * test and we at or past the end, bump up Maxmem
 			 * so that we keep going. The first bad page
 			 * will terminate the loop.
 			 */
 			if (phys_avail[pa_indx] == pa) {
 				phys_avail[pa_indx] += PAGE_SIZE;
 			} else {
 				pa_indx++;
 				if (pa_indx == PHYS_AVAIL_ARRAY_END) {
 					printf(
 		"Too many holes in the physical address space, giving up\n");
 					pa_indx--;
 					full = TRUE;
 					goto do_dump_avail;
 				}
 				phys_avail[pa_indx++] = pa;	/* start */
 				phys_avail[pa_indx] = pa + PAGE_SIZE; /* end */
 			}
 			physmem++;
 do_dump_avail:
 			if (dump_avail[da_indx] == pa) {
 				dump_avail[da_indx] += PAGE_SIZE;
 			} else {
 				da_indx++;
 				if (da_indx == DUMP_AVAIL_ARRAY_END) {
 					da_indx--;
 					goto do_next;
 				}
 				dump_avail[da_indx++] = pa; /* start */
 				dump_avail[da_indx] = pa + PAGE_SIZE; /* end */
 			}
 do_next:
 			if (full)
 				break;
 		}
 	}
 	*pte = 0;
 	invltlb();
 	if (memtest != 0)
 		printf("\n");
 
 	/*
 	 * XXX
 	 * The last chunk must contain at least one page plus the message
 	 * buffer to avoid complicating other code (message buffer address
 	 * calculation, etc.).
 	 */
 	while (phys_avail[pa_indx - 1] + PAGE_SIZE +
 	    round_page(msgbufsize) >= phys_avail[pa_indx]) {
 		physmem -= atop(phys_avail[pa_indx] - phys_avail[pa_indx - 1]);
 		phys_avail[pa_indx--] = 0;
 		phys_avail[pa_indx--] = 0;
 	}
 
 	Maxmem = atop(phys_avail[pa_indx]);
 
 	/* Trim off space for the message buffer. */
 	phys_avail[pa_indx] -= round_page(msgbufsize);
 
 	/* Map the message buffer. */
 	msgbufp = (struct msgbuf *)PHYS_TO_DMAP(phys_avail[pa_indx]);
 }
 
 u_int64_t
 hammer_time(u_int64_t modulep, u_int64_t physfree)
 {
 	caddr_t kmdp;
 	int gsel_tss, x;
 	struct pcpu *pc;
 	struct nmi_pcpu *np;
 	struct xstate_hdr *xhdr;
 	u_int64_t msr;
 	char *env;
 	size_t kstack0_sz;
 
 	thread0.td_kstack = physfree + KERNBASE;
 	thread0.td_kstack_pages = KSTACK_PAGES;
 	kstack0_sz = thread0.td_kstack_pages * PAGE_SIZE;
 	bzero((void *)thread0.td_kstack, kstack0_sz);
 	physfree += kstack0_sz;
 
 	/*
  	 * This may be done better later if it gets more high level
  	 * components in it. If so just link td->td_proc here.
 	 */
 	proc_linkup0(&proc0, &thread0);
 
 	preload_metadata = (caddr_t)(uintptr_t)(modulep + KERNBASE);
 	preload_bootstrap_relocate(KERNBASE);
 	kmdp = preload_search_by_type("elf kernel");
 	if (kmdp == NULL)
 		kmdp = preload_search_by_type("elf64 kernel");
 	boothowto = MD_FETCH(kmdp, MODINFOMD_HOWTO, int);
 	kern_envp = MD_FETCH(kmdp, MODINFOMD_ENVP, char *) + KERNBASE;
 #ifdef DDB
 	ksym_start = MD_FETCH(kmdp, MODINFOMD_SSYM, uintptr_t);
 	ksym_end = MD_FETCH(kmdp, MODINFOMD_ESYM, uintptr_t);
 #endif
 
 	/* Init basic tunables, hz etc */
 	init_param1();
 
 	/*
 	 * make gdt memory segments
 	 */
 	for (x = 0; x < NGDT; x++) {
 		if (x != GPROC0_SEL && x != (GPROC0_SEL + 1) &&
 		    x != GUSERLDT_SEL && x != (GUSERLDT_SEL) + 1)
 			ssdtosd(&gdt_segs[x], &gdt[x]);
 	}
 	gdt_segs[GPROC0_SEL].ssd_base = (uintptr_t)&common_tss[0];
 	ssdtosyssd(&gdt_segs[GPROC0_SEL],
 	    (struct system_segment_descriptor *)&gdt[GPROC0_SEL]);
 
 	r_gdt.rd_limit = NGDT * sizeof(gdt[0]) - 1;
 	r_gdt.rd_base =  (long) gdt;
 	lgdt(&r_gdt);
 	pc = &__pcpu[0];
 
 	wrmsr(MSR_FSBASE, 0);		/* User value */
 	wrmsr(MSR_GSBASE, (u_int64_t)pc);
 	wrmsr(MSR_KGSBASE, 0);		/* User value while in the kernel */
 
 	pcpu_init(pc, 0, sizeof(struct pcpu));
 	dpcpu_init((void *)(physfree + KERNBASE), 0);
 	physfree += DPCPU_SIZE;
 	PCPU_SET(prvspace, pc);
 	PCPU_SET(curthread, &thread0);
 	PCPU_SET(tssp, &common_tss[0]);
 	PCPU_SET(commontssp, &common_tss[0]);
 	PCPU_SET(tss, (struct system_segment_descriptor *)&gdt[GPROC0_SEL]);
 	PCPU_SET(ldt, (struct system_segment_descriptor *)&gdt[GUSERLDT_SEL]);
 	PCPU_SET(fs32p, &gdt[GUFS32_SEL]);
 	PCPU_SET(gs32p, &gdt[GUGS32_SEL]);
 
 	/*
 	 * Initialize mutexes.
 	 *
 	 * icu_lock: in order to allow an interrupt to occur in a critical
 	 * 	     section, to set pcpu->ipending (etc...) properly, we
 	 *	     must be able to get the icu lock, so it can't be
 	 *	     under witness.
 	 */
 	mutex_init();
 	mtx_init(&icu_lock, "icu", NULL, MTX_SPIN | MTX_NOWITNESS);
 	mtx_init(&dt_lock, "descriptor tables", NULL, MTX_DEF);
 
 	/* exceptions */
 	for (x = 0; x < NIDT; x++)
 		setidt(x, &IDTVEC(rsvd), SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_DE, &IDTVEC(div),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_DB, &IDTVEC(dbg),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_NMI, &IDTVEC(nmi),  SDT_SYSIGT, SEL_KPL, 2);
  	setidt(IDT_BP, &IDTVEC(bpt),  SDT_SYSIGT, SEL_UPL, 0);
 	setidt(IDT_OF, &IDTVEC(ofl),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_BR, &IDTVEC(bnd),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_UD, &IDTVEC(ill),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_NM, &IDTVEC(dna),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_DF, &IDTVEC(dblfault), SDT_SYSIGT, SEL_KPL, 1);
 	setidt(IDT_FPUGP, &IDTVEC(fpusegm),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_TS, &IDTVEC(tss),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_NP, &IDTVEC(missing),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_SS, &IDTVEC(stk),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_GP, &IDTVEC(prot),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_PF, &IDTVEC(page),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_MF, &IDTVEC(fpu),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_AC, &IDTVEC(align), SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_MC, &IDTVEC(mchk),  SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_XF, &IDTVEC(xmm), SDT_SYSIGT, SEL_KPL, 0);
 #ifdef KDTRACE_HOOKS
 	setidt(IDT_DTRACE_RET, &IDTVEC(dtrace_ret), SDT_SYSIGT, SEL_UPL, 0);
 #endif
 #ifdef XENHVM
 	setidt(IDT_EVTCHN, &IDTVEC(xen_intr_upcall), SDT_SYSIGT, SEL_UPL, 0);
 #endif
 
 	r_idt.rd_limit = sizeof(idt0) - 1;
 	r_idt.rd_base = (long) idt;
 	lidt(&r_idt);
 
 	/*
 	 * Initialize the i8254 before the console so that console
 	 * initialization can use DELAY().
 	 */
 	i8254_init();
 
 	/*
 	 * Use vt(4) by default for UEFI boot (during the sc(4)/vt(4)
 	 * transition).
 	 */
 	if (kmdp != NULL && preload_search_info(kmdp,
 	    MODINFO_METADATA | MODINFOMD_EFI_MAP) != NULL)
 		vty_set_preferred(VTY_VT);
 
 	identify_cpu();		/* Final stage of CPU initialization */
 	initializecpu();	/* Initialize CPU registers */
 	initializecpucache();
 
 	/* doublefault stack space, runs on ist1 */
 	common_tss[0].tss_ist1 = (long)&dblfault_stack[sizeof(dblfault_stack)];
 
 	/*
 	 * NMI stack, runs on ist2.  The pcpu pointer is stored just
 	 * above the start of the ist2 stack.
 	 */
 	np = ((struct nmi_pcpu *) &nmi0_stack[sizeof(nmi0_stack)]) - 1;
 	np->np_pcpu = (register_t) pc;
 	common_tss[0].tss_ist2 = (long) np;
 
 	/* Set the IO permission bitmap (empty due to tss seg limit) */
 	common_tss[0].tss_iobase = sizeof(struct amd64tss) +
 	    IOPAGES * PAGE_SIZE;
 
 	gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
 	ltr(gsel_tss);
 
 	/* Set up the fast syscall stuff */
 	msr = rdmsr(MSR_EFER) | EFER_SCE;
 	wrmsr(MSR_EFER, msr);
 	wrmsr(MSR_LSTAR, (u_int64_t)IDTVEC(fast_syscall));
 	wrmsr(MSR_CSTAR, (u_int64_t)IDTVEC(fast_syscall32));
 	msr = ((u_int64_t)GSEL(GCODE_SEL, SEL_KPL) << 32) |
 	      ((u_int64_t)GSEL(GUCODE32_SEL, SEL_UPL) << 48);
 	wrmsr(MSR_STAR, msr);
 	wrmsr(MSR_SF_MASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_D);
 
 	getmemsize(kmdp, physfree);
 	init_param2(physmem);
 
 	/* now running on new page tables, configured,and u/iom is accessible */
 
 	cninit();
 
 #ifdef DEV_ISA
 #ifdef DEV_ATPIC
 	elcr_probe();
 	atpic_startup();
 #else
 	/* Reset and mask the atpics and leave them shut down. */
 	atpic_reset();
 
 	/*
 	 * Point the ICU spurious interrupt vectors at the APIC spurious
 	 * interrupt handler.
 	 */
 	setidt(IDT_IO_INTS + 7, IDTVEC(spuriousint), SDT_SYSIGT, SEL_KPL, 0);
 	setidt(IDT_IO_INTS + 15, IDTVEC(spuriousint), SDT_SYSIGT, SEL_KPL, 0);
 #endif
 #else
 #error "have you forgotten the isa device?";
 #endif
 
 	kdb_init();
 
 #ifdef KDB
 	if (boothowto & RB_KDB)
 		kdb_enter(KDB_WHY_BOOTFLAGS,
 		    "Boot flags requested debugger");
 #endif
 
 	msgbufinit(msgbufp, msgbufsize);
 	fpuinit();
 
 	/*
 	 * Set up thread0 pcb after fpuinit calculated pcb + fpu save
 	 * area size.  Zero out the extended state header in fpu save
 	 * area.
 	 */
 	thread0.td_pcb = get_pcb_td(&thread0);
 	bzero(get_pcb_user_save_td(&thread0), cpu_max_ext_state_size);
 	if (use_xsave) {
 		xhdr = (struct xstate_hdr *)(get_pcb_user_save_td(&thread0) +
 		    1);
 		xhdr->xstate_bv = xsave_mask;
 	}
 	/* make an initial tss so cpu can get interrupt stack on syscall! */
 	common_tss[0].tss_rsp0 = (vm_offset_t)thread0.td_pcb;
 	/* Ensure the stack is aligned to 16 bytes */
 	common_tss[0].tss_rsp0 &= ~0xFul;
 	PCPU_SET(rsp0, common_tss[0].tss_rsp0);
 	PCPU_SET(curpcb, thread0.td_pcb);
 
 	/* transfer to user mode */
 
 	_ucodesel = GSEL(GUCODE_SEL, SEL_UPL);
 	_udatasel = GSEL(GUDATA_SEL, SEL_UPL);
 	_ucode32sel = GSEL(GUCODE32_SEL, SEL_UPL);
 	_ufssel = GSEL(GUFS32_SEL, SEL_UPL);
 	_ugssel = GSEL(GUGS32_SEL, SEL_UPL);
 
 	load_ds(_udatasel);
 	load_es(_udatasel);
 	load_fs(_ufssel);
 
 	/* setup proc 0's pcb */
 	thread0.td_pcb->pcb_flags = 0;
 	thread0.td_pcb->pcb_cr3 = KPML4phys; /* PCID 0 is reserved for kernel */
 	thread0.td_frame = &proc0_tf;
 
         env = getenv("kernelname");
 	if (env != NULL)
 		strlcpy(kernelname, env, sizeof(kernelname));
 
 	cpu_probe_amdc1e();
 
 #ifdef FDT
 	x86_init_fdt();
 #endif
 
 	/* Location of kernel stack for locore */
 	return ((u_int64_t)thread0.td_pcb);
 }
 
 void
 cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
 {
 
 	pcpu->pc_acpi_id = 0xffffffff;
 }
 
 static int
 smap_sysctl_handler(SYSCTL_HANDLER_ARGS)
 {
 	struct bios_smap *smapbase;
 	struct bios_smap_xattr smap;
 	caddr_t kmdp;
 	uint32_t *smapattr;
 	int count, error, i;
 
 	/* Retrieve the system memory map from the loader. */
 	kmdp = preload_search_by_type("elf kernel");
 	if (kmdp == NULL)
 		kmdp = preload_search_by_type("elf64 kernel");
 	smapbase = (struct bios_smap *)preload_search_info(kmdp,
 	    MODINFO_METADATA | MODINFOMD_SMAP);
 	if (smapbase == NULL)
 		return (0);
 	smapattr = (uint32_t *)preload_search_info(kmdp,
 	    MODINFO_METADATA | MODINFOMD_SMAP_XATTR);
 	count = *((uint32_t *)smapbase - 1) / sizeof(*smapbase);
 	error = 0;
 	for (i = 0; i < count; i++) {
 		smap.base = smapbase[i].base;
 		smap.length = smapbase[i].length;
 		smap.type = smapbase[i].type;
 		if (smapattr != NULL)
 			smap.xattr = smapattr[i];
 		else
 			smap.xattr = 0;
 		error = SYSCTL_OUT(req, &smap, sizeof(smap));
 	}
 	return (error);
 }
 SYSCTL_PROC(_machdep, OID_AUTO, smap, CTLTYPE_OPAQUE|CTLFLAG_RD, NULL, 0,
     smap_sysctl_handler, "S,bios_smap_xattr", "Raw BIOS SMAP data");
 
 static int
 efi_map_sysctl_handler(SYSCTL_HANDLER_ARGS)
 {
 	struct efi_map_header *efihdr;
 	caddr_t kmdp;
 	uint32_t efisize;
 
 	kmdp = preload_search_by_type("elf kernel");
 	if (kmdp == NULL)
 		kmdp = preload_search_by_type("elf64 kernel");
 	efihdr = (struct efi_map_header *)preload_search_info(kmdp,
 	    MODINFO_METADATA | MODINFOMD_EFI_MAP);
 	if (efihdr == NULL)
 		return (0);
 	efisize = *((uint32_t *)efihdr - 1);
 	return (SYSCTL_OUT(req, efihdr, efisize));
 }
 SYSCTL_PROC(_machdep, OID_AUTO, efi_map, CTLTYPE_OPAQUE|CTLFLAG_RD, NULL, 0,
     efi_map_sysctl_handler, "S,efi_map_header", "Raw EFI Memory Map");
 
 void
 spinlock_enter(void)
 {
 	struct thread *td;
 	register_t flags;
 
 	td = curthread;
 	if (td->td_md.md_spinlock_count == 0) {
 		flags = intr_disable();
 		td->td_md.md_spinlock_count = 1;
 		td->td_md.md_saved_flags = flags;
 	} else
 		td->td_md.md_spinlock_count++;
 	critical_enter();
 }
 
 void
 spinlock_exit(void)
 {
 	struct thread *td;
 	register_t flags;
 
 	td = curthread;
 	critical_exit();
 	flags = td->td_md.md_saved_flags;
 	td->td_md.md_spinlock_count--;
 	if (td->td_md.md_spinlock_count == 0)
 		intr_restore(flags);
 }
 
 /*
  * Construct a PCB from a trapframe. This is called from kdb_trap() where
  * we want to start a backtrace from the function that caused us to enter
  * the debugger. We have the context in the trapframe, but base the trace
  * on the PCB. The PCB doesn't have to be perfect, as long as it contains
  * enough for a backtrace.
  */
 void
 makectx(struct trapframe *tf, struct pcb *pcb)
 {
 
 	pcb->pcb_r12 = tf->tf_r12;
 	pcb->pcb_r13 = tf->tf_r13;
 	pcb->pcb_r14 = tf->tf_r14;
 	pcb->pcb_r15 = tf->tf_r15;
 	pcb->pcb_rbp = tf->tf_rbp;
 	pcb->pcb_rbx = tf->tf_rbx;
 	pcb->pcb_rip = tf->tf_rip;
 	pcb->pcb_rsp = tf->tf_rsp;
 }
 
 int
 ptrace_set_pc(struct thread *td, unsigned long addr)
 {
 
 	td->td_frame->tf_rip = addr;
 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
 	return (0);
 }
 
 int
 ptrace_single_step(struct thread *td)
 {
 	td->td_frame->tf_rflags |= PSL_T;
 	return (0);
 }
 
 int
 ptrace_clear_single_step(struct thread *td)
 {
 	td->td_frame->tf_rflags &= ~PSL_T;
 	return (0);
 }
 
 int
 fill_regs(struct thread *td, struct reg *regs)
 {
 	struct trapframe *tp;
 
 	tp = td->td_frame;
 	return (fill_frame_regs(tp, regs));
 }
 
 int
 fill_frame_regs(struct trapframe *tp, struct reg *regs)
 {
 	regs->r_r15 = tp->tf_r15;
 	regs->r_r14 = tp->tf_r14;
 	regs->r_r13 = tp->tf_r13;
 	regs->r_r12 = tp->tf_r12;
 	regs->r_r11 = tp->tf_r11;
 	regs->r_r10 = tp->tf_r10;
 	regs->r_r9  = tp->tf_r9;
 	regs->r_r8  = tp->tf_r8;
 	regs->r_rdi = tp->tf_rdi;
 	regs->r_rsi = tp->tf_rsi;
 	regs->r_rbp = tp->tf_rbp;
 	regs->r_rbx = tp->tf_rbx;
 	regs->r_rdx = tp->tf_rdx;
 	regs->r_rcx = tp->tf_rcx;
 	regs->r_rax = tp->tf_rax;
 	regs->r_rip = tp->tf_rip;
 	regs->r_cs = tp->tf_cs;
 	regs->r_rflags = tp->tf_rflags;
 	regs->r_rsp = tp->tf_rsp;
 	regs->r_ss = tp->tf_ss;
 	if (tp->tf_flags & TF_HASSEGS) {
 		regs->r_ds = tp->tf_ds;
 		regs->r_es = tp->tf_es;
 		regs->r_fs = tp->tf_fs;
 		regs->r_gs = tp->tf_gs;
 	} else {
 		regs->r_ds = 0;
 		regs->r_es = 0;
 		regs->r_fs = 0;
 		regs->r_gs = 0;
 	}
 	return (0);
 }
 
 int
 set_regs(struct thread *td, struct reg *regs)
 {
 	struct trapframe *tp;
 	register_t rflags;
 
 	tp = td->td_frame;
 	rflags = regs->r_rflags & 0xffffffff;
 	if (!EFL_SECURE(rflags, tp->tf_rflags) || !CS_SECURE(regs->r_cs))
 		return (EINVAL);
 	tp->tf_r15 = regs->r_r15;
 	tp->tf_r14 = regs->r_r14;
 	tp->tf_r13 = regs->r_r13;
 	tp->tf_r12 = regs->r_r12;
 	tp->tf_r11 = regs->r_r11;
 	tp->tf_r10 = regs->r_r10;
 	tp->tf_r9  = regs->r_r9;
 	tp->tf_r8  = regs->r_r8;
 	tp->tf_rdi = regs->r_rdi;
 	tp->tf_rsi = regs->r_rsi;
 	tp->tf_rbp = regs->r_rbp;
 	tp->tf_rbx = regs->r_rbx;
 	tp->tf_rdx = regs->r_rdx;
 	tp->tf_rcx = regs->r_rcx;
 	tp->tf_rax = regs->r_rax;
 	tp->tf_rip = regs->r_rip;
 	tp->tf_cs = regs->r_cs;
 	tp->tf_rflags = rflags;
 	tp->tf_rsp = regs->r_rsp;
 	tp->tf_ss = regs->r_ss;
 	if (0) {	/* XXXKIB */
 		tp->tf_ds = regs->r_ds;
 		tp->tf_es = regs->r_es;
 		tp->tf_fs = regs->r_fs;
 		tp->tf_gs = regs->r_gs;
 		tp->tf_flags = TF_HASSEGS;
 	}
 	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
 	return (0);
 }
 
 /* XXX check all this stuff! */
 /* externalize from sv_xmm */
 static void
 fill_fpregs_xmm(struct savefpu *sv_xmm, struct fpreg *fpregs)
 {
 	struct envxmm *penv_fpreg = (struct envxmm *)&fpregs->fpr_env;
 	struct envxmm *penv_xmm = &sv_xmm->sv_env;
 	int i;
 
 	/* pcb -> fpregs */
 	bzero(fpregs, sizeof(*fpregs));
 
 	/* FPU control/status */
 	penv_fpreg->en_cw = penv_xmm->en_cw;
 	penv_fpreg->en_sw = penv_xmm->en_sw;
 	penv_fpreg->en_tw = penv_xmm->en_tw;
 	penv_fpreg->en_opcode = penv_xmm->en_opcode;
 	penv_fpreg->en_rip = penv_xmm->en_rip;
 	penv_fpreg->en_rdp = penv_xmm->en_rdp;
 	penv_fpreg->en_mxcsr = penv_xmm->en_mxcsr;
 	penv_fpreg->en_mxcsr_mask = penv_xmm->en_mxcsr_mask;
 
 	/* FPU registers */
 	for (i = 0; i < 8; ++i)
 		bcopy(sv_xmm->sv_fp[i].fp_acc.fp_bytes, fpregs->fpr_acc[i], 10);
 
 	/* SSE registers */
 	for (i = 0; i < 16; ++i)
 		bcopy(sv_xmm->sv_xmm[i].xmm_bytes, fpregs->fpr_xacc[i], 16);
 }
 
 /* internalize from fpregs into sv_xmm */
 static void
 set_fpregs_xmm(struct fpreg *fpregs, struct savefpu *sv_xmm)
 {
 	struct envxmm *penv_xmm = &sv_xmm->sv_env;
 	struct envxmm *penv_fpreg = (struct envxmm *)&fpregs->fpr_env;
 	int i;
 
 	/* fpregs -> pcb */
 	/* FPU control/status */
 	penv_xmm->en_cw = penv_fpreg->en_cw;
 	penv_xmm->en_sw = penv_fpreg->en_sw;
 	penv_xmm->en_tw = penv_fpreg->en_tw;
 	penv_xmm->en_opcode = penv_fpreg->en_opcode;
 	penv_xmm->en_rip = penv_fpreg->en_rip;
 	penv_xmm->en_rdp = penv_fpreg->en_rdp;
 	penv_xmm->en_mxcsr = penv_fpreg->en_mxcsr;
 	penv_xmm->en_mxcsr_mask = penv_fpreg->en_mxcsr_mask & cpu_mxcsr_mask;
 
 	/* FPU registers */
 	for (i = 0; i < 8; ++i)
 		bcopy(fpregs->fpr_acc[i], sv_xmm->sv_fp[i].fp_acc.fp_bytes, 10);
 
 	/* SSE registers */
 	for (i = 0; i < 16; ++i)
 		bcopy(fpregs->fpr_xacc[i], sv_xmm->sv_xmm[i].xmm_bytes, 16);
 }
 
 /* externalize from td->pcb */
 int
 fill_fpregs(struct thread *td, struct fpreg *fpregs)
 {
 
 	KASSERT(td == curthread || TD_IS_SUSPENDED(td) ||
 	    P_SHOULDSTOP(td->td_proc),
 	    ("not suspended thread %p", td));
 	fpugetregs(td);
 	fill_fpregs_xmm(get_pcb_user_save_td(td), fpregs);
 	return (0);
 }
 
 /* internalize to td->pcb */
 int
 set_fpregs(struct thread *td, struct fpreg *fpregs)
 {
 
 	set_fpregs_xmm(fpregs, get_pcb_user_save_td(td));
 	fpuuserinited(td);
 	return (0);
 }
 
 /*
  * Get machine context.
  */
 int
 get_mcontext(struct thread *td, mcontext_t *mcp, int flags)
 {
 	struct pcb *pcb;
 	struct trapframe *tp;
 
 	pcb = td->td_pcb;
 	tp = td->td_frame;
 	PROC_LOCK(curthread->td_proc);
 	mcp->mc_onstack = sigonstack(tp->tf_rsp);
 	PROC_UNLOCK(curthread->td_proc);
 	mcp->mc_r15 = tp->tf_r15;
 	mcp->mc_r14 = tp->tf_r14;
 	mcp->mc_r13 = tp->tf_r13;
 	mcp->mc_r12 = tp->tf_r12;
 	mcp->mc_r11 = tp->tf_r11;
 	mcp->mc_r10 = tp->tf_r10;
 	mcp->mc_r9  = tp->tf_r9;
 	mcp->mc_r8  = tp->tf_r8;
 	mcp->mc_rdi = tp->tf_rdi;
 	mcp->mc_rsi = tp->tf_rsi;
 	mcp->mc_rbp = tp->tf_rbp;
 	mcp->mc_rbx = tp->tf_rbx;
 	mcp->mc_rcx = tp->tf_rcx;
 	mcp->mc_rflags = tp->tf_rflags;
 	if (flags & GET_MC_CLEAR_RET) {
 		mcp->mc_rax = 0;
 		mcp->mc_rdx = 0;
 		mcp->mc_rflags &= ~PSL_C;
 	} else {
 		mcp->mc_rax = tp->tf_rax;
 		mcp->mc_rdx = tp->tf_rdx;
 	}
 	mcp->mc_rip = tp->tf_rip;
 	mcp->mc_cs = tp->tf_cs;
 	mcp->mc_rsp = tp->tf_rsp;
 	mcp->mc_ss = tp->tf_ss;
 	mcp->mc_ds = tp->tf_ds;
 	mcp->mc_es = tp->tf_es;
 	mcp->mc_fs = tp->tf_fs;
 	mcp->mc_gs = tp->tf_gs;
 	mcp->mc_flags = tp->tf_flags;
 	mcp->mc_len = sizeof(*mcp);
 	get_fpcontext(td, mcp, NULL, 0);
 	mcp->mc_fsbase = pcb->pcb_fsbase;
 	mcp->mc_gsbase = pcb->pcb_gsbase;
 	mcp->mc_xfpustate = 0;
 	mcp->mc_xfpustate_len = 0;
 	bzero(mcp->mc_spare, sizeof(mcp->mc_spare));
 	return (0);
 }
 
 /*
  * Set machine context.
  *
  * However, we don't set any but the user modifiable flags, and we won't
  * touch the cs selector.
  */
 int
 set_mcontext(struct thread *td, mcontext_t *mcp)
 {
 	struct pcb *pcb;
 	struct trapframe *tp;
 	char *xfpustate;
 	long rflags;
 	int ret;
 
 	pcb = td->td_pcb;
 	tp = td->td_frame;
 	if (mcp->mc_len != sizeof(*mcp) ||
 	    (mcp->mc_flags & ~_MC_FLAG_MASK) != 0)
 		return (EINVAL);
 	rflags = (mcp->mc_rflags & PSL_USERCHANGE) |
 	    (tp->tf_rflags & ~PSL_USERCHANGE);
 	if (mcp->mc_flags & _MC_HASFPXSTATE) {
 		if (mcp->mc_xfpustate_len > cpu_max_ext_state_size -
 		    sizeof(struct savefpu))
 			return (EINVAL);
 		xfpustate = __builtin_alloca(mcp->mc_xfpustate_len);
 		ret = copyin((void *)mcp->mc_xfpustate, xfpustate,
 		    mcp->mc_xfpustate_len);
 		if (ret != 0)
 			return (ret);
 	} else
 		xfpustate = NULL;
 	ret = set_fpcontext(td, mcp, xfpustate, mcp->mc_xfpustate_len);
 	if (ret != 0)
 		return (ret);
 	tp->tf_r15 = mcp->mc_r15;
 	tp->tf_r14 = mcp->mc_r14;
 	tp->tf_r13 = mcp->mc_r13;
 	tp->tf_r12 = mcp->mc_r12;
 	tp->tf_r11 = mcp->mc_r11;
 	tp->tf_r10 = mcp->mc_r10;
 	tp->tf_r9  = mcp->mc_r9;
 	tp->tf_r8  = mcp->mc_r8;
 	tp->tf_rdi = mcp->mc_rdi;
 	tp->tf_rsi = mcp->mc_rsi;
 	tp->tf_rbp = mcp->mc_rbp;
 	tp->tf_rbx = mcp->mc_rbx;
 	tp->tf_rdx = mcp->mc_rdx;
 	tp->tf_rcx = mcp->mc_rcx;
 	tp->tf_rax = mcp->mc_rax;
 	tp->tf_rip = mcp->mc_rip;
 	tp->tf_rflags = rflags;
 	tp->tf_rsp = mcp->mc_rsp;
 	tp->tf_ss = mcp->mc_ss;
 	tp->tf_flags = mcp->mc_flags;
 	if (tp->tf_flags & TF_HASSEGS) {
 		tp->tf_ds = mcp->mc_ds;
 		tp->tf_es = mcp->mc_es;
 		tp->tf_fs = mcp->mc_fs;
 		tp->tf_gs = mcp->mc_gs;
 	}
 	if (mcp->mc_flags & _MC_HASBASES) {
 		pcb->pcb_fsbase = mcp->mc_fsbase;
 		pcb->pcb_gsbase = mcp->mc_gsbase;
 	}
 	set_pcb_flags(pcb, PCB_FULL_IRET);
 	return (0);
 }
 
 static void
 get_fpcontext(struct thread *td, mcontext_t *mcp, char *xfpusave,
     size_t xfpusave_len)
 {
 	size_t max_len, len;
 
 	mcp->mc_ownedfp = fpugetregs(td);
 	bcopy(get_pcb_user_save_td(td), &mcp->mc_fpstate[0],
 	    sizeof(mcp->mc_fpstate));
 	mcp->mc_fpformat = fpuformat();
 	if (!use_xsave || xfpusave_len == 0)
 		return;
 	max_len = cpu_max_ext_state_size - sizeof(struct savefpu);
 	len = xfpusave_len;
 	if (len > max_len) {
 		len = max_len;
 		bzero(xfpusave + max_len, len - max_len);
 	}
 	mcp->mc_flags |= _MC_HASFPXSTATE;
 	mcp->mc_xfpustate_len = len;
 	bcopy(get_pcb_user_save_td(td) + 1, xfpusave, len);
 }
 
 static int
 set_fpcontext(struct thread *td, mcontext_t *mcp, char *xfpustate,
     size_t xfpustate_len)
 {
 	struct savefpu *fpstate;
 	int error;
 
 	if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
 		return (0);
 	else if (mcp->mc_fpformat != _MC_FPFMT_XMM)
 		return (EINVAL);
 	else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE) {
 		/* We don't care what state is left in the FPU or PCB. */
 		fpstate_drop(td);
 		error = 0;
 	} else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
 	    mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
 		fpstate = (struct savefpu *)&mcp->mc_fpstate;
 		fpstate->sv_env.en_mxcsr &= cpu_mxcsr_mask;
 		error = fpusetregs(td, fpstate, xfpustate, xfpustate_len);
 	} else
 		return (EINVAL);
 	return (error);
 }
 
 void
 fpstate_drop(struct thread *td)
 {
 
 	KASSERT(PCB_USER_FPU(td->td_pcb), ("fpstate_drop: kernel-owned fpu"));
 	critical_enter();
 	if (PCPU_GET(fpcurthread) == td)
 		fpudrop();
 	/*
 	 * XXX force a full drop of the fpu.  The above only drops it if we
 	 * owned it.
 	 *
 	 * XXX I don't much like fpugetuserregs()'s semantics of doing a full
 	 * drop.  Dropping only to the pcb matches fnsave's behaviour.
 	 * We only need to drop to !PCB_INITDONE in sendsig().  But
 	 * sendsig() is the only caller of fpugetuserregs()... perhaps we just
 	 * have too many layers.
 	 */
 	clear_pcb_flags(curthread->td_pcb,
 	    PCB_FPUINITDONE | PCB_USERFPUINITDONE);
 	critical_exit();
 }
 
 int
 fill_dbregs(struct thread *td, struct dbreg *dbregs)
 {
 	struct pcb *pcb;
 
 	if (td == NULL) {
 		dbregs->dr[0] = rdr0();
 		dbregs->dr[1] = rdr1();
 		dbregs->dr[2] = rdr2();
 		dbregs->dr[3] = rdr3();
 		dbregs->dr[6] = rdr6();
 		dbregs->dr[7] = rdr7();
 	} else {
 		pcb = td->td_pcb;
 		dbregs->dr[0] = pcb->pcb_dr0;
 		dbregs->dr[1] = pcb->pcb_dr1;
 		dbregs->dr[2] = pcb->pcb_dr2;
 		dbregs->dr[3] = pcb->pcb_dr3;
 		dbregs->dr[6] = pcb->pcb_dr6;
 		dbregs->dr[7] = pcb->pcb_dr7;
 	}
 	dbregs->dr[4] = 0;
 	dbregs->dr[5] = 0;
 	dbregs->dr[8] = 0;
 	dbregs->dr[9] = 0;
 	dbregs->dr[10] = 0;
 	dbregs->dr[11] = 0;
 	dbregs->dr[12] = 0;
 	dbregs->dr[13] = 0;
 	dbregs->dr[14] = 0;
 	dbregs->dr[15] = 0;
 	return (0);
 }
 
 int
 set_dbregs(struct thread *td, struct dbreg *dbregs)
 {
 	struct pcb *pcb;
 	int i;
 
 	if (td == NULL) {
 		load_dr0(dbregs->dr[0]);
 		load_dr1(dbregs->dr[1]);
 		load_dr2(dbregs->dr[2]);
 		load_dr3(dbregs->dr[3]);
 		load_dr6(dbregs->dr[6]);
 		load_dr7(dbregs->dr[7]);
 	} else {
 		/*
 		 * Don't let an illegal value for dr7 get set.  Specifically,
 		 * check for undefined settings.  Setting these bit patterns
 		 * result in undefined behaviour and can lead to an unexpected
 		 * TRCTRAP or a general protection fault right here.
 		 * Upper bits of dr6 and dr7 must not be set
 		 */
 		for (i = 0; i < 4; i++) {
 			if (DBREG_DR7_ACCESS(dbregs->dr[7], i) == 0x02)
 				return (EINVAL);
 			if (td->td_frame->tf_cs == _ucode32sel &&
 			    DBREG_DR7_LEN(dbregs->dr[7], i) == DBREG_DR7_LEN_8)
 				return (EINVAL);
 		}
 		if ((dbregs->dr[6] & 0xffffffff00000000ul) != 0 ||
 		    (dbregs->dr[7] & 0xffffffff00000000ul) != 0)
 			return (EINVAL);
 
 		pcb = td->td_pcb;
 
 		/*
 		 * Don't let a process set a breakpoint that is not within the
 		 * process's address space.  If a process could do this, it
 		 * could halt the system by setting a breakpoint in the kernel
 		 * (if ddb was enabled).  Thus, we need to check to make sure
 		 * that no breakpoints are being enabled for addresses outside
 		 * process's address space.
 		 *
 		 * XXX - what about when the watched area of the user's
 		 * address space is written into from within the kernel
 		 * ... wouldn't that still cause a breakpoint to be generated
 		 * from within kernel mode?
 		 */
 
 		if (DBREG_DR7_ENABLED(dbregs->dr[7], 0)) {
 			/* dr0 is enabled */
 			if (dbregs->dr[0] >= VM_MAXUSER_ADDRESS)
 				return (EINVAL);
 		}
 		if (DBREG_DR7_ENABLED(dbregs->dr[7], 1)) {
 			/* dr1 is enabled */
 			if (dbregs->dr[1] >= VM_MAXUSER_ADDRESS)
 				return (EINVAL);
 		}
 		if (DBREG_DR7_ENABLED(dbregs->dr[7], 2)) {
 			/* dr2 is enabled */
 			if (dbregs->dr[2] >= VM_MAXUSER_ADDRESS)
 				return (EINVAL);
 		}
 		if (DBREG_DR7_ENABLED(dbregs->dr[7], 3)) {
 			/* dr3 is enabled */
 			if (dbregs->dr[3] >= VM_MAXUSER_ADDRESS)
 				return (EINVAL);
 		}
 
 		pcb->pcb_dr0 = dbregs->dr[0];
 		pcb->pcb_dr1 = dbregs->dr[1];
 		pcb->pcb_dr2 = dbregs->dr[2];
 		pcb->pcb_dr3 = dbregs->dr[3];
 		pcb->pcb_dr6 = dbregs->dr[6];
 		pcb->pcb_dr7 = dbregs->dr[7];
 
 		set_pcb_flags(pcb, PCB_DBREGS);
 	}
 
 	return (0);
 }
 
 void
 reset_dbregs(void)
 {
 
 	load_dr7(0);	/* Turn off the control bits first */
 	load_dr0(0);
 	load_dr1(0);
 	load_dr2(0);
 	load_dr3(0);
 	load_dr6(0);
 }
 
 /*
  * Return > 0 if a hardware breakpoint has been hit, and the
  * breakpoint was in user space.  Return 0, otherwise.
  */
 int
 user_dbreg_trap(void)
 {
         u_int64_t dr7, dr6; /* debug registers dr6 and dr7 */
         u_int64_t bp;       /* breakpoint bits extracted from dr6 */
         int nbp;            /* number of breakpoints that triggered */
         caddr_t addr[4];    /* breakpoint addresses */
         int i;
         
         dr7 = rdr7();
         if ((dr7 & 0x000000ff) == 0) {
                 /*
                  * all GE and LE bits in the dr7 register are zero,
                  * thus the trap couldn't have been caused by the
                  * hardware debug registers
                  */
                 return 0;
         }
 
         nbp = 0;
         dr6 = rdr6();
         bp = dr6 & 0x0000000f;
 
         if (!bp) {
                 /*
                  * None of the breakpoint bits are set meaning this
                  * trap was not caused by any of the debug registers
                  */
                 return 0;
         }
 
         /*
          * at least one of the breakpoints were hit, check to see
          * which ones and if any of them are user space addresses
          */
 
         if (bp & 0x01) {
                 addr[nbp++] = (caddr_t)rdr0();
         }
         if (bp & 0x02) {
                 addr[nbp++] = (caddr_t)rdr1();
         }
         if (bp & 0x04) {
                 addr[nbp++] = (caddr_t)rdr2();
         }
         if (bp & 0x08) {
                 addr[nbp++] = (caddr_t)rdr3();
         }
 
         for (i = 0; i < nbp; i++) {
                 if (addr[i] < (caddr_t)VM_MAXUSER_ADDRESS) {
                         /*
                          * addr[i] is in user space
                          */
                         return nbp;
                 }
         }
 
         /*
          * None of the breakpoints are in user space.
          */
         return 0;
 }
 
 #ifdef KDB
 
 /*
  * Provide inb() and outb() as functions.  They are normally only available as
  * inline functions, thus cannot be called from the debugger.
  */
 
 /* silence compiler warnings */
 u_char inb_(u_short);
 void outb_(u_short, u_char);
 
 u_char
 inb_(u_short port)
 {
 	return inb(port);
 }
 
 void
 outb_(u_short port, u_char data)
 {
 	outb(port, data);
 }
 
 #endif /* KDB */
Index: stable/10
===================================================================
--- stable/10	(revision 292550)
+++ stable/10	(revision 292551)

Property changes on: stable/10
___________________________________________________________________
Modified: svn:mergeinfo
## -0,0 +0,1 ##
   Merged /head:r277735