diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c index ccd6c39a861c..a519414d7452 100644 --- a/sys/amd64/amd64/trap.c +++ b/sys/amd64/amd64/trap.c @@ -1,989 +1,980 @@ /*- * Copyright (C) 1994, David Greenman * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * the University of Utah, and 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: @(#)trap.c 7.4 (Berkeley) 5/13/91 */ #include __FBSDID("$FreeBSD$"); /* * AMD64 Trap and System call handling */ #include "opt_clock.h" #include "opt_cpu.h" #include "opt_hwpmc_hooks.h" #include "opt_isa.h" #include "opt_kdb.h" #include "opt_kdtrace.h" #include "opt_ktrace.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #ifdef HWPMC_HOOKS #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #ifdef SMP #include #endif #include #ifdef KDTRACE_HOOKS #include /* * This is a hook which is initialised by the dtrace module * to handle traps which might occur during DTrace probe * execution. */ dtrace_trap_func_t dtrace_trap_func; dtrace_doubletrap_func_t dtrace_doubletrap_func; /* * This is a hook which is initialised by the systrace module * when it is loaded. This keeps the DTrace syscall provider * implementation opaque. */ systrace_probe_func_t systrace_probe_func; #endif extern void trap(struct trapframe *frame); extern void syscall(struct trapframe *frame); void dblfault_handler(struct trapframe *frame); static int trap_pfault(struct trapframe *, int); static void trap_fatal(struct trapframe *, vm_offset_t); #define MAX_TRAP_MSG 30 static char *trap_msg[] = { "", /* 0 unused */ "privileged instruction fault", /* 1 T_PRIVINFLT */ "", /* 2 unused */ "breakpoint instruction fault", /* 3 T_BPTFLT */ "", /* 4 unused */ "", /* 5 unused */ "arithmetic trap", /* 6 T_ARITHTRAP */ "", /* 7 unused */ "", /* 8 unused */ "general protection fault", /* 9 T_PROTFLT */ "trace trap", /* 10 T_TRCTRAP */ "", /* 11 unused */ "page fault", /* 12 T_PAGEFLT */ "", /* 13 unused */ "alignment fault", /* 14 T_ALIGNFLT */ "", /* 15 unused */ "", /* 16 unused */ "", /* 17 unused */ "integer divide fault", /* 18 T_DIVIDE */ "non-maskable interrupt trap", /* 19 T_NMI */ "overflow trap", /* 20 T_OFLOW */ "FPU bounds check fault", /* 21 T_BOUND */ "FPU device not available", /* 22 T_DNA */ "double fault", /* 23 T_DOUBLEFLT */ "FPU operand fetch fault", /* 24 T_FPOPFLT */ "invalid TSS fault", /* 25 T_TSSFLT */ "segment not present fault", /* 26 T_SEGNPFLT */ "stack fault", /* 27 T_STKFLT */ "machine check trap", /* 28 T_MCHK */ "SIMD floating-point exception", /* 29 T_XMMFLT */ "reserved (unknown) fault", /* 30 T_RESERVED */ }; #ifdef KDB static int kdb_on_nmi = 1; SYSCTL_INT(_machdep, OID_AUTO, kdb_on_nmi, CTLFLAG_RW, &kdb_on_nmi, 0, "Go to KDB on NMI"); #endif static int panic_on_nmi = 1; SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW, &panic_on_nmi, 0, "Panic on NMI"); static int prot_fault_translation = 0; SYSCTL_INT(_machdep, OID_AUTO, prot_fault_translation, CTLFLAG_RW, &prot_fault_translation, 0, "Select signal to deliver on protection fault"); extern char *syscallnames[]; /* * Exception, fault, and trap interface to the FreeBSD kernel. * This common code is called from assembly language IDT gate entry * routines that prepare a suitable stack frame, and restore this * frame after the exception has been processed. */ void trap(struct trapframe *frame) { struct thread *td = curthread; struct proc *p = td->td_proc; int i = 0, ucode = 0, code; u_int type; register_t addr = 0; ksiginfo_t ksi; PCPU_INC(cnt.v_trap); type = frame->tf_trapno; #ifdef SMP #ifdef STOP_NMI /* Handler for NMI IPIs used for stopping CPUs. */ if (type == T_NMI) { if (ipi_nmi_handler() == 0) goto out; } #endif /* STOP_NMI */ #endif /* SMP */ #ifdef KDB if (kdb_active) { kdb_reenter(); goto out; } #endif #ifdef HWPMC_HOOKS /* * CPU PMCs interrupt using an NMI. If the PMC module is * active, pass the 'rip' value to the PMC module's interrupt * handler. A return value of '1' from the handler means that * the NMI was handled by it and we can return immediately. */ if (type == T_NMI && pmc_intr && (*pmc_intr)(PCPU_GET(cpuid), frame)) goto out; #endif #ifdef KDTRACE_HOOKS /* * A trap can occur while DTrace executes a probe. Before * executing the probe, DTrace blocks re-scheduling and sets * a flag in it's per-cpu flags to indicate that it doesn't * want to fault. On returning from the the probe, the no-fault * flag is cleared and finally re-scheduling is enabled. * * If the DTrace kernel module has registered a trap handler, * call it and if it returns non-zero, assume that it has * handled the trap and modified the trap frame so that this * function can return normally. */ if (dtrace_trap_func != NULL) if ((*dtrace_trap_func)(frame, type)) goto out; #endif if ((frame->tf_rflags & PSL_I) == 0) { /* * Buggy application or kernel code has disabled * interrupts and then trapped. Enabling interrupts * now is wrong, but it is better than running with * interrupts disabled until they are accidentally * enabled later. */ if (ISPL(frame->tf_cs) == SEL_UPL) printf( "pid %ld (%s): trap %d with interrupts disabled\n", (long)curproc->p_pid, curthread->td_name, type); else if (type != T_NMI && type != T_BPTFLT && type != T_TRCTRAP) { /* * XXX not quite right, since this may be for a * multiple fault in user mode. */ printf("kernel trap %d with interrupts disabled\n", type); /* * We shouldn't enable interrupts while holding a * spin lock or servicing an NMI. */ if (type != T_NMI && td->td_md.md_spinlock_count == 0) enable_intr(); } } code = frame->tf_err; if (type == T_PAGEFLT) { /* * If we get a page fault while in a critical section, then * it is most likely a fatal kernel page fault. The kernel * is already going to panic trying to get a sleep lock to * do the VM lookup, so just consider it a fatal trap so the * kernel can print out a useful trap message and even get * to the debugger. * * If we get a page fault while holding a non-sleepable * lock, then it is most likely a fatal kernel page fault. * If WITNESS is enabled, then it's going to whine about * bogus LORs with various VM locks, so just skip to the * fatal trap handling directly. */ if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK | WARN_GIANTOK, NULL, "Kernel page fault") != 0) trap_fatal(frame, frame->tf_addr); } if (ISPL(frame->tf_cs) == SEL_UPL) { /* user trap */ td->td_pticks = 0; td->td_frame = frame; addr = frame->tf_rip; if (td->td_ucred != p->p_ucred) cred_update_thread(td); switch (type) { case T_PRIVINFLT: /* privileged instruction fault */ i = SIGILL; ucode = ILL_PRVOPC; break; case T_BPTFLT: /* bpt instruction fault */ case T_TRCTRAP: /* trace trap */ enable_intr(); frame->tf_rflags &= ~PSL_T; i = SIGTRAP; ucode = (type == T_TRCTRAP ? TRAP_TRACE : TRAP_BRKPT); break; case T_ARITHTRAP: /* arithmetic trap */ ucode = fputrap(); if (ucode == -1) goto userout; i = SIGFPE; break; case T_PROTFLT: /* general protection fault */ i = SIGBUS; ucode = BUS_OBJERR; break; case T_STKFLT: /* stack fault */ case T_SEGNPFLT: /* segment not present fault */ i = SIGBUS; ucode = BUS_ADRERR; break; case T_TSSFLT: /* invalid TSS fault */ i = SIGBUS; ucode = BUS_OBJERR; break; case T_DOUBLEFLT: /* double fault */ default: i = SIGBUS; ucode = BUS_OBJERR; break; case T_PAGEFLT: /* page fault */ addr = frame->tf_addr; i = trap_pfault(frame, TRUE); if (i == -1) goto userout; if (i == 0) goto user; if (i == SIGSEGV) ucode = SEGV_MAPERR; else { if (prot_fault_translation == 0) { /* * Autodetect. * This check also covers the images * without the ABI-tag ELF note. */ if (p->p_osrel >= 700004) { i = SIGSEGV; ucode = SEGV_ACCERR; } else { i = SIGBUS; ucode = BUS_PAGE_FAULT; } } else if (prot_fault_translation == 1) { /* * Always compat mode. */ i = SIGBUS; ucode = BUS_PAGE_FAULT; } else { /* * Always SIGSEGV mode. */ i = SIGSEGV; ucode = SEGV_ACCERR; } } break; case T_DIVIDE: /* integer divide fault */ ucode = FPE_INTDIV; i = SIGFPE; break; #ifdef DEV_ISA case T_NMI: /* machine/parity/power fail/"kitchen sink" faults */ - /* XXX Giant */ if (isa_nmi(code) == 0) { #ifdef KDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (kdb_on_nmi) { printf ("NMI ... going to debugger\n"); kdb_trap(type, 0, frame); } #endif /* KDB */ goto userout; } else if (panic_on_nmi) panic("NMI indicates hardware failure"); break; #endif /* DEV_ISA */ case T_OFLOW: /* integer overflow fault */ ucode = FPE_INTOVF; i = SIGFPE; break; case T_BOUND: /* bounds check fault */ ucode = FPE_FLTSUB; i = SIGFPE; break; case T_DNA: /* transparent fault (due to context switch "late") */ fpudna(); goto userout; case T_FPOPFLT: /* FPU operand fetch fault */ ucode = ILL_COPROC; i = SIGILL; break; case T_XMMFLT: /* SIMD floating-point exception */ ucode = 0; /* XXX */ i = SIGFPE; break; } } else { /* kernel trap */ KASSERT(cold || td->td_ucred != NULL, ("kernel trap doesn't have ucred")); switch (type) { case T_PAGEFLT: /* page fault */ (void) trap_pfault(frame, FALSE); goto out; case T_DNA: /* * The kernel is apparently using fpu for copying. * XXX this should be fatal unless the kernel has * registered such use. */ fpudna(); printf("fpudna in kernel mode!\n"); goto out; case T_STKFLT: /* stack fault */ break; case T_PROTFLT: /* general protection fault */ case T_SEGNPFLT: /* segment not present fault */ if (td->td_intr_nesting_level != 0) break; /* * Invalid segment selectors and out of bounds * %rip's and %rsp's can be set up in user mode. * This causes a fault in kernel mode when the * kernel tries to return to user mode. We want * to get this fault so that we can fix the * problem here and not have to check all the * selectors and pointers when the user changes * them. */ if (frame->tf_rip == (long)doreti_iret) { frame->tf_rip = (long)doreti_iret_fault; goto out; } if (PCPU_GET(curpcb)->pcb_onfault != NULL) { frame->tf_rip = (long)PCPU_GET(curpcb)->pcb_onfault; goto out; } break; case T_TSSFLT: /* * PSL_NT can be set in user mode and isn't cleared * automatically when the kernel is entered. This * causes a TSS fault when the kernel attempts to * `iret' because the TSS link is uninitialized. We * want to get this fault so that we can fix the * problem here and not every time the kernel is * entered. */ if (frame->tf_rflags & PSL_NT) { frame->tf_rflags &= ~PSL_NT; goto out; } break; case T_TRCTRAP: /* trace trap */ /* * Ignore debug register trace traps due to * accesses in the user's address space, which * can happen under several conditions such as * if a user sets a watchpoint on a buffer and * then passes that buffer to a system call. * We still want to get TRCTRAPS for addresses * in kernel space because that is useful when * debugging the kernel. */ if (user_dbreg_trap()) { /* * Reset breakpoint bits because the * processor doesn't */ /* XXX check upper bits here */ load_dr6(rdr6() & 0xfffffff0); goto out; } /* * FALLTHROUGH (TRCTRAP kernel mode, kernel address) */ case T_BPTFLT: /* * If KDB is enabled, let it handle the debugger trap. * Otherwise, debugger traps "can't happen". */ #ifdef KDB if (kdb_trap(type, 0, frame)) goto out; #endif break; #ifdef DEV_ISA case T_NMI: - /* XXX Giant */ /* machine/parity/power fail/"kitchen sink" faults */ if (isa_nmi(code) == 0) { #ifdef KDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (kdb_on_nmi) { printf ("NMI ... going to debugger\n"); kdb_trap(type, 0, frame); } #endif /* KDB */ goto out; } else if (panic_on_nmi == 0) goto out; /* FALLTHROUGH */ #endif /* DEV_ISA */ } trap_fatal(frame, 0); goto out; } /* Translate fault for emulators (e.g. Linux) */ if (*p->p_sysent->sv_transtrap) i = (*p->p_sysent->sv_transtrap)(i, type); ksiginfo_init_trap(&ksi); ksi.ksi_signo = i; ksi.ksi_code = ucode; ksi.ksi_trapno = type; ksi.ksi_addr = (void *)addr; trapsignal(td, &ksi); #ifdef DEBUG if (type <= MAX_TRAP_MSG) { uprintf("fatal process exception: %s", trap_msg[type]); if ((type == T_PAGEFLT) || (type == T_PROTFLT)) uprintf(", fault VA = 0x%lx", frame->tf_addr); uprintf("\n"); } #endif user: userret(td, frame); mtx_assert(&Giant, MA_NOTOWNED); userout: out: return; } static int trap_pfault(frame, usermode) struct trapframe *frame; int usermode; { vm_offset_t va; struct vmspace *vm = NULL; vm_map_t map; int rv = 0; vm_prot_t ftype; struct thread *td = curthread; struct proc *p = td->td_proc; vm_offset_t eva = frame->tf_addr; va = trunc_page(eva); if (va >= VM_MIN_KERNEL_ADDRESS) { /* * Don't allow user-mode faults in kernel address space. */ if (usermode) goto nogo; map = kernel_map; } else { /* * This is a fault on non-kernel virtual memory. * vm is initialized above to NULL. If curproc is NULL * or curproc->p_vmspace is NULL the fault is fatal. */ if (p != NULL) vm = p->p_vmspace; if (vm == NULL) goto nogo; map = &vm->vm_map; } /* * PGEX_I is defined only if the execute disable bit capability is * supported and enabled. */ if (frame->tf_err & PGEX_W) ftype = VM_PROT_WRITE; else if ((frame->tf_err & PGEX_I) && pg_nx != 0) ftype = VM_PROT_EXECUTE; else ftype = VM_PROT_READ; if (map != kernel_map) { /* * Keep swapout from messing with us during this * critical time. */ PROC_LOCK(p); ++p->p_lock; PROC_UNLOCK(p); /* Fault in the user page: */ rv = vm_fault(map, va, ftype, (ftype & VM_PROT_WRITE) ? VM_FAULT_DIRTY : VM_FAULT_NORMAL); PROC_LOCK(p); --p->p_lock; PROC_UNLOCK(p); } else { /* * Don't have to worry about process locking or stacks in the * kernel. */ rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL); } if (rv == KERN_SUCCESS) return (0); nogo: if (!usermode) { if (td->td_intr_nesting_level == 0 && PCPU_GET(curpcb)->pcb_onfault != NULL) { frame->tf_rip = (long)PCPU_GET(curpcb)->pcb_onfault; return (0); } trap_fatal(frame, eva); return (-1); } return((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV); } static void trap_fatal(frame, eva) struct trapframe *frame; vm_offset_t eva; { int code, ss; u_int type; long esp; struct soft_segment_descriptor softseg; char *msg; code = frame->tf_err; type = frame->tf_trapno; sdtossd(&gdt[NGDT * PCPU_GET(cpuid) + IDXSEL(frame->tf_cs & 0xffff)], &softseg); if (type <= MAX_TRAP_MSG) msg = trap_msg[type]; else msg = "UNKNOWN"; printf("\n\nFatal trap %d: %s while in %s mode\n", type, msg, ISPL(frame->tf_cs) == SEL_UPL ? "user" : "kernel"); #ifdef SMP /* two separate prints in case of a trap on an unmapped page */ printf("cpuid = %d; ", PCPU_GET(cpuid)); printf("apic id = %02x\n", PCPU_GET(apic_id)); #endif if (type == T_PAGEFLT) { printf("fault virtual address = 0x%lx\n", eva); printf("fault code = %s %s %s, %s\n", code & PGEX_U ? "user" : "supervisor", code & PGEX_W ? "write" : "read", code & PGEX_I ? "instruction" : "data", code & PGEX_P ? "protection violation" : "page not present"); } printf("instruction pointer = 0x%lx:0x%lx\n", frame->tf_cs & 0xffff, frame->tf_rip); if (ISPL(frame->tf_cs) == SEL_UPL) { ss = frame->tf_ss & 0xffff; esp = frame->tf_rsp; } else { ss = GSEL(GDATA_SEL, SEL_KPL); esp = (long)&frame->tf_rsp; } printf("stack pointer = 0x%x:0x%lx\n", ss, esp); printf("frame pointer = 0x%x:0x%lx\n", ss, frame->tf_rbp); printf("code segment = base 0x%lx, limit 0x%lx, type 0x%x\n", softseg.ssd_base, softseg.ssd_limit, softseg.ssd_type); printf(" = DPL %d, pres %d, long %d, def32 %d, gran %d\n", softseg.ssd_dpl, softseg.ssd_p, softseg.ssd_long, softseg.ssd_def32, softseg.ssd_gran); printf("processor eflags = "); if (frame->tf_rflags & PSL_T) printf("trace trap, "); if (frame->tf_rflags & PSL_I) printf("interrupt enabled, "); if (frame->tf_rflags & PSL_NT) printf("nested task, "); if (frame->tf_rflags & PSL_RF) printf("resume, "); printf("IOPL = %ld\n", (frame->tf_rflags & PSL_IOPL) >> 12); printf("current process = "); if (curproc) { printf("%lu (%s)\n", (u_long)curproc->p_pid, curthread->td_name ? curthread->td_name : ""); } else { printf("Idle\n"); } #ifdef KDB if (debugger_on_panic || kdb_active) if (kdb_trap(type, 0, frame)) return; #endif printf("trap number = %d\n", type); if (type <= MAX_TRAP_MSG) panic("%s", trap_msg[type]); else panic("unknown/reserved trap"); } /* * Double fault handler. Called when a fault occurs while writing * a frame for a trap/exception onto the stack. This usually occurs * when the stack overflows (such is the case with infinite recursion, * for example). */ void dblfault_handler(struct trapframe *frame) { #ifdef KDTRACE_HOOKS if (dtrace_doubletrap_func != NULL) (*dtrace_doubletrap_func)(); #endif printf("\nFatal double fault\n"); printf("rip = 0x%lx\n", frame->tf_rip); printf("rsp = 0x%lx\n", frame->tf_rsp); printf("rbp = 0x%lx\n", frame->tf_rbp); #ifdef SMP /* two separate prints in case of a trap on an unmapped page */ printf("cpuid = %d; ", PCPU_GET(cpuid)); printf("apic id = %02x\n", PCPU_GET(apic_id)); #endif panic("double fault"); } /* * syscall - system call request C handler * * A system call is essentially treated as a trap. */ void syscall(struct trapframe *frame) { caddr_t params; struct sysent *callp; struct thread *td = curthread; struct proc *p = td->td_proc; register_t orig_tf_rflags; int error; int narg; register_t args[8]; register_t *argp; u_int code; int reg, regcnt; ksiginfo_t ksi; PCPU_INC(cnt.v_syscall); #ifdef DIAGNOSTIC if (ISPL(frame->tf_cs) != SEL_UPL) { panic("syscall"); /* NOT REACHED */ } #endif reg = 0; regcnt = 6; td->td_pticks = 0; td->td_frame = frame; if (td->td_ucred != p->p_ucred) cred_update_thread(td); params = (caddr_t)frame->tf_rsp + sizeof(register_t); code = frame->tf_rax; orig_tf_rflags = frame->tf_rflags; if (p->p_sysent->sv_prepsyscall) { - /* - * The prep code is MP aware. - */ (*p->p_sysent->sv_prepsyscall)(frame, (int *)args, &code, ¶ms); } else { if (code == SYS_syscall || code == SYS___syscall) { code = frame->tf_rdi; reg++; regcnt--; } } if (p->p_sysent->sv_mask) code &= p->p_sysent->sv_mask; if (code >= p->p_sysent->sv_size) callp = &p->p_sysent->sv_table[0]; else callp = &p->p_sysent->sv_table[code]; narg = callp->sy_narg; - - /* - * copyin and the ktrsyscall()/ktrsysret() code is MP-aware - */ KASSERT(narg <= sizeof(args) / sizeof(args[0]), ("Too many syscall arguments!")); error = 0; argp = &frame->tf_rdi; argp += reg; bcopy(argp, args, sizeof(args[0]) * regcnt); if (narg > regcnt) { KASSERT(params != NULL, ("copyin args with no params!")); error = copyin(params, &args[regcnt], (narg - regcnt) * sizeof(args[0])); } argp = &args[0]; #ifdef KTRACE if (KTRPOINT(td, KTR_SYSCALL)) ktrsyscall(code, narg, argp); #endif CTR4(KTR_SYSC, "syscall enter thread %p pid %d proc %s code %d", td, td->td_proc->p_pid, td->td_name, code); td->td_syscalls++; if (error == 0) { td->td_retval[0] = 0; td->td_retval[1] = frame->tf_rdx; STOPEVENT(p, S_SCE, narg); PTRACESTOP_SC(p, td, S_PT_SCE); #ifdef KDTRACE_HOOKS /* * If the systrace module has registered it's probe * callback and if there is a probe active for the * syscall 'entry', process the probe. */ if (systrace_probe_func != NULL && callp->sy_entry != 0) (*systrace_probe_func)(callp->sy_entry, code, callp, args); #endif AUDIT_SYSCALL_ENTER(code, td); error = (*callp->sy_call)(td, argp); AUDIT_SYSCALL_EXIT(error, td); /* Save the latest error return value. */ td->td_errno = error; #ifdef KDTRACE_HOOKS /* * If the systrace module has registered it's probe * callback and if there is a probe active for the * syscall 'return', process the probe. */ if (systrace_probe_func != NULL && callp->sy_return != 0) (*systrace_probe_func)(callp->sy_return, code, callp, args); #endif } switch (error) { case 0: frame->tf_rax = td->td_retval[0]; frame->tf_rdx = td->td_retval[1]; frame->tf_rflags &= ~PSL_C; break; case ERESTART: /* * Reconstruct pc, we know that 'syscall' is 2 bytes. * We have to do a full context restore so that %r10 * (which was holding the value of %rcx) is restored for * the next iteration. */ frame->tf_rip -= frame->tf_err; frame->tf_r10 = frame->tf_rcx; td->td_pcb->pcb_flags |= PCB_FULLCTX; break; case EJUSTRETURN: break; default: if (p->p_sysent->sv_errsize) { if (error >= p->p_sysent->sv_errsize) error = -1; /* XXX */ else error = p->p_sysent->sv_errtbl[error]; } frame->tf_rax = error; frame->tf_rflags |= PSL_C; break; } /* * Traced syscall. */ if (orig_tf_rflags & PSL_T) { frame->tf_rflags &= ~PSL_T; ksiginfo_init_trap(&ksi); ksi.ksi_signo = SIGTRAP; ksi.ksi_code = TRAP_TRACE; ksi.ksi_addr = (void *)frame->tf_rip; trapsignal(td, &ksi); } /* * Check for misbehavior. */ WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning", (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"); KASSERT(td->td_critnest == 0, ("System call %s returning in a critical section", (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???")); KASSERT(td->td_locks == 0, ("System call %s returning with %d locks held", (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???", td->td_locks)); /* * Handle reschedule and other end-of-syscall issues */ userret(td, frame); CTR4(KTR_SYSC, "syscall exit thread %p pid %d proc %s code %d", td, td->td_proc->p_pid, td->td_name, code); #ifdef KTRACE if (KTRPOINT(td, KTR_SYSRET)) ktrsysret(code, error, td->td_retval[0]); #endif /* * This works because errno is findable through the * register set. If we ever support an emulation where this * is not the case, this code will need to be revisited. */ STOPEVENT(p, S_SCX, code); PTRACESTOP_SC(p, td, S_PT_SCX); } diff --git a/sys/i386/i386/in_cksum.c b/sys/i386/i386/in_cksum.c index be7d8a37e364..c0e92d6e7ff7 100644 --- a/sys/i386/i386/in_cksum.c +++ b/sys/i386/i386/in_cksum.c @@ -1,494 +1,491 @@ /*- * Copyright (c) 1990 The Regents of the University of California. * All rights reserved. * * 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. * 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 tahoe: in_cksum.c 1.2 86/01/05 * from: @(#)in_cksum.c 1.3 (Berkeley) 1/19/91 */ #include __FBSDID("$FreeBSD$"); -/* - * MPsafe: alfred - */ #include #include #include #include #include #include #include /* * Checksum routine for Internet Protocol family headers. * * This routine is very heavily used in the network * code and should be modified for each CPU to be as fast as possible. * * This implementation is 386 version. */ #undef ADDCARRY #define ADDCARRY(x) if ((x) > 0xffff) (x) -= 0xffff /* * icc needs to be special cased here, as the asm code below results * in broken code if compiled with icc. */ #if !defined(__GNUCLIKE_ASM) || defined(__INTEL_COMPILER) /* non gcc parts stolen from sys/alpha/alpha/in_cksum.c */ #define REDUCE32 \ { \ q_util.q = sum; \ sum = q_util.s[0] + q_util.s[1] + q_util.s[2] + q_util.s[3]; \ } #define REDUCE16 \ { \ q_util.q = sum; \ l_util.l = q_util.s[0] + q_util.s[1] + q_util.s[2] + q_util.s[3]; \ sum = l_util.s[0] + l_util.s[1]; \ ADDCARRY(sum); \ } #endif #define REDUCE {sum = (sum & 0xffff) + (sum >> 16); ADDCARRY(sum);} #if !defined(__GNUCLIKE_ASM) || defined(__INTEL_COMPILER) static const u_int32_t in_masks[] = { /*0 bytes*/ /*1 byte*/ /*2 bytes*/ /*3 bytes*/ 0x00000000, 0x000000FF, 0x0000FFFF, 0x00FFFFFF, /* offset 0 */ 0x00000000, 0x0000FF00, 0x00FFFF00, 0xFFFFFF00, /* offset 1 */ 0x00000000, 0x00FF0000, 0xFFFF0000, 0xFFFF0000, /* offset 2 */ 0x00000000, 0xFF000000, 0xFF000000, 0xFF000000, /* offset 3 */ }; union l_util { u_int16_t s[2]; u_int32_t l; }; union q_util { u_int16_t s[4]; u_int32_t l[2]; u_int64_t q; }; static u_int64_t in_cksumdata(const u_int32_t *lw, int len) { u_int64_t sum = 0; u_int64_t prefilled; int offset; union q_util q_util; if ((3 & (long) lw) == 0 && len == 20) { sum = (u_int64_t) lw[0] + lw[1] + lw[2] + lw[3] + lw[4]; REDUCE32; return sum; } if ((offset = 3 & (long) lw) != 0) { const u_int32_t *masks = in_masks + (offset << 2); lw = (u_int32_t *) (((long) lw) - offset); sum = *lw++ & masks[len >= 3 ? 3 : len]; len -= 4 - offset; if (len <= 0) { REDUCE32; return sum; } } #if 0 /* * Force to cache line boundary. */ offset = 32 - (0x1f & (long) lw); if (offset < 32 && len > offset) { len -= offset; if (4 & offset) { sum += (u_int64_t) lw[0]; lw += 1; } if (8 & offset) { sum += (u_int64_t) lw[0] + lw[1]; lw += 2; } if (16 & offset) { sum += (u_int64_t) lw[0] + lw[1] + lw[2] + lw[3]; lw += 4; } } #endif /* * access prefilling to start load of next cache line. * then add current cache line * save result of prefilling for loop iteration. */ prefilled = lw[0]; while ((len -= 32) >= 4) { u_int64_t prefilling = lw[8]; sum += prefilled + lw[1] + lw[2] + lw[3] + lw[4] + lw[5] + lw[6] + lw[7]; lw += 8; prefilled = prefilling; } if (len >= 0) { sum += prefilled + lw[1] + lw[2] + lw[3] + lw[4] + lw[5] + lw[6] + lw[7]; lw += 8; } else { len += 32; } while ((len -= 16) >= 0) { sum += (u_int64_t) lw[0] + lw[1] + lw[2] + lw[3]; lw += 4; } len += 16; while ((len -= 4) >= 0) { sum += (u_int64_t) *lw++; } len += 4; if (len > 0) sum += (u_int64_t) (in_masks[len] & *lw); REDUCE32; return sum; } u_short in_addword(u_short a, u_short b) { u_int64_t sum = a + b; ADDCARRY(sum); return (sum); } u_short in_pseudo(u_int32_t a, u_int32_t b, u_int32_t c) { u_int64_t sum; union q_util q_util; union l_util l_util; sum = (u_int64_t) a + b + c; REDUCE16; return (sum); } u_short in_cksum_skip(struct mbuf *m, int len, int skip) { u_int64_t sum = 0; int mlen = 0; int clen = 0; caddr_t addr; union q_util q_util; union l_util l_util; len -= skip; for (; skip && m; m = m->m_next) { if (m->m_len > skip) { mlen = m->m_len - skip; addr = mtod(m, caddr_t) + skip; goto skip_start; } else { skip -= m->m_len; } } for (; m && len; m = m->m_next) { if (m->m_len == 0) continue; mlen = m->m_len; addr = mtod(m, caddr_t); skip_start: if (len < mlen) mlen = len; if ((clen ^ (long) addr) & 1) sum += in_cksumdata((const u_int32_t *)addr, mlen) << 8; else sum += in_cksumdata((const u_int32_t *)addr, mlen); clen += mlen; len -= mlen; } REDUCE16; return (~sum & 0xffff); } u_int in_cksum_hdr(const struct ip *ip) { u_int64_t sum = in_cksumdata((const u_int32_t *)ip, sizeof(struct ip)); union q_util q_util; union l_util l_util; REDUCE16; return (~sum & 0xffff); } #else /* * These asm statements require __volatile because they pass information * via the condition codes. GCC does not currently provide a way to specify * the condition codes as an input or output operand. * * The LOAD macro below is effectively a prefetch into cache. GCC will * load the value into a register but will not use it. Since modern CPUs * reorder operations, this will generally take place in parallel with * other calculations. */ u_short in_cksum_skip(m, len, skip) struct mbuf *m; int len; int skip; { register u_short *w; register unsigned sum = 0; register int mlen = 0; int byte_swapped = 0; union { char c[2]; u_short s; } su; len -= skip; for (; skip && m; m = m->m_next) { if (m->m_len > skip) { mlen = m->m_len - skip; w = (u_short *)(mtod(m, u_char *) + skip); goto skip_start; } else { skip -= m->m_len; } } for (;m && len; m = m->m_next) { if (m->m_len == 0) continue; w = mtod(m, u_short *); if (mlen == -1) { /* * The first byte of this mbuf is the continuation * of a word spanning between this mbuf and the * last mbuf. */ /* su.c[0] is already saved when scanning previous * mbuf. sum was REDUCEd when we found mlen == -1 */ su.c[1] = *(u_char *)w; sum += su.s; w = (u_short *)((char *)w + 1); mlen = m->m_len - 1; len--; } else mlen = m->m_len; skip_start: if (len < mlen) mlen = len; len -= mlen; /* * Force to long boundary so we do longword aligned * memory operations */ if (3 & (int) w) { REDUCE; if ((1 & (int) w) && (mlen > 0)) { sum <<= 8; su.c[0] = *(char *)w; w = (u_short *)((char *)w + 1); mlen--; byte_swapped = 1; } if ((2 & (int) w) && (mlen >= 2)) { sum += *w++; mlen -= 2; } } /* * Advance to a 486 cache line boundary. */ if (4 & (int) w && mlen >= 4) { __asm __volatile ( "addl %1, %0\n" "adcl $0, %0" : "+r" (sum) : "g" (((const u_int32_t *)w)[0]) ); w += 2; mlen -= 4; } if (8 & (int) w && mlen >= 8) { __asm __volatile ( "addl %1, %0\n" "adcl %2, %0\n" "adcl $0, %0" : "+r" (sum) : "g" (((const u_int32_t *)w)[0]), "g" (((const u_int32_t *)w)[1]) ); w += 4; mlen -= 8; } /* * Do as much of the checksum as possible 32 bits at at time. * In fact, this loop is unrolled to make overhead from * branches &c small. */ mlen -= 1; while ((mlen -= 32) >= 0) { /* * Add with carry 16 words and fold in the last * carry by adding a 0 with carry. * * The early ADD(16) and the LOAD(32) are to load * the next 2 cache lines in advance on 486's. The * 486 has a penalty of 2 clock cycles for loading * a cache line, plus whatever time the external * memory takes to load the first word(s) addressed. * These penalties are unavoidable. Subsequent * accesses to a cache line being loaded (and to * other external memory?) are delayed until the * whole load finishes. These penalties are mostly * avoided by not accessing external memory for * 8 cycles after the ADD(16) and 12 cycles after * the LOAD(32). The loop terminates when mlen * is initially 33 (not 32) to guaranteed that * the LOAD(32) is within bounds. */ __asm __volatile ( "addl %1, %0\n" "adcl %2, %0\n" "adcl %3, %0\n" "adcl %4, %0\n" "adcl %5, %0\n" "mov %6, %%eax\n" "adcl %7, %0\n" "adcl %8, %0\n" "adcl %9, %0\n" "adcl $0, %0" : "+r" (sum) : "g" (((const u_int32_t *)w)[4]), "g" (((const u_int32_t *)w)[0]), "g" (((const u_int32_t *)w)[1]), "g" (((const u_int32_t *)w)[2]), "g" (((const u_int32_t *)w)[3]), "g" (((const u_int32_t *)w)[8]), "g" (((const u_int32_t *)w)[5]), "g" (((const u_int32_t *)w)[6]), "g" (((const u_int32_t *)w)[7]) : "eax" ); w += 16; } mlen += 32 + 1; if (mlen >= 32) { __asm __volatile ( "addl %1, %0\n" "adcl %2, %0\n" "adcl %3, %0\n" "adcl %4, %0\n" "adcl %5, %0\n" "adcl %6, %0\n" "adcl %7, %0\n" "adcl %8, %0\n" "adcl $0, %0" : "+r" (sum) : "g" (((const u_int32_t *)w)[4]), "g" (((const u_int32_t *)w)[0]), "g" (((const u_int32_t *)w)[1]), "g" (((const u_int32_t *)w)[2]), "g" (((const u_int32_t *)w)[3]), "g" (((const u_int32_t *)w)[5]), "g" (((const u_int32_t *)w)[6]), "g" (((const u_int32_t *)w)[7]) ); w += 16; mlen -= 32; } if (mlen >= 16) { __asm __volatile ( "addl %1, %0\n" "adcl %2, %0\n" "adcl %3, %0\n" "adcl %4, %0\n" "adcl $0, %0" : "+r" (sum) : "g" (((const u_int32_t *)w)[0]), "g" (((const u_int32_t *)w)[1]), "g" (((const u_int32_t *)w)[2]), "g" (((const u_int32_t *)w)[3]) ); w += 8; mlen -= 16; } if (mlen >= 8) { __asm __volatile ( "addl %1, %0\n" "adcl %2, %0\n" "adcl $0, %0" : "+r" (sum) : "g" (((const u_int32_t *)w)[0]), "g" (((const u_int32_t *)w)[1]) ); w += 4; mlen -= 8; } if (mlen == 0 && byte_swapped == 0) continue; /* worth 1% maybe ?? */ REDUCE; while ((mlen -= 2) >= 0) { sum += *w++; } if (byte_swapped) { sum <<= 8; byte_swapped = 0; if (mlen == -1) { su.c[1] = *(char *)w; sum += su.s; mlen = 0; } else mlen = -1; } else if (mlen == -1) /* * This mbuf has odd number of bytes. * There could be a word split betwen * this mbuf and the next mbuf. * Save the last byte (to prepend to next mbuf). */ su.c[0] = *(char *)w; } if (len) printf("%s: out of data by %d\n", __func__, len); if (mlen == -1) { /* The last mbuf has odd # of bytes. Follow the standard (the odd byte is shifted left by 8 bits) */ su.c[1] = 0; sum += su.s; } REDUCE; return (~sum & 0xffff); } #endif diff --git a/sys/i386/i386/trap.c b/sys/i386/i386/trap.c index 1ef34ff53187..95e33e30b7c7 100644 --- a/sys/i386/i386/trap.c +++ b/sys/i386/i386/trap.c @@ -1,1171 +1,1161 @@ /*- * Copyright (C) 1994, David Greenman * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * the University of Utah, and 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: @(#)trap.c 7.4 (Berkeley) 5/13/91 */ #include __FBSDID("$FreeBSD$"); /* * 386 Trap and System call handling */ #include "opt_clock.h" #include "opt_cpu.h" #include "opt_hwpmc_hooks.h" #include "opt_isa.h" #include "opt_kdb.h" #include "opt_kdtrace.h" #include "opt_ktrace.h" #include "opt_npx.h" #include "opt_trap.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #ifdef HWPMC_HOOKS #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #ifdef SMP #include #endif #include #include #ifdef POWERFAIL_NMI #include #include #endif #ifdef KDTRACE_HOOKS #include /* * This is a hook which is initialised by the dtrace module * to handle traps which might occur during DTrace probe * execution. */ dtrace_trap_func_t dtrace_trap_func; dtrace_doubletrap_func_t dtrace_doubletrap_func; /* * This is a hook which is initialised by the systrace module * when it is loaded. This keeps the DTrace syscall provider * implementation opaque. */ systrace_probe_func_t systrace_probe_func; #endif extern void trap(struct trapframe *frame); extern void syscall(struct trapframe *frame); static int trap_pfault(struct trapframe *, int, vm_offset_t); static void trap_fatal(struct trapframe *, vm_offset_t); void dblfault_handler(void); extern inthand_t IDTVEC(lcall_syscall); #define MAX_TRAP_MSG 30 static char *trap_msg[] = { "", /* 0 unused */ "privileged instruction fault", /* 1 T_PRIVINFLT */ "", /* 2 unused */ "breakpoint instruction fault", /* 3 T_BPTFLT */ "", /* 4 unused */ "", /* 5 unused */ "arithmetic trap", /* 6 T_ARITHTRAP */ "", /* 7 unused */ "", /* 8 unused */ "general protection fault", /* 9 T_PROTFLT */ "trace trap", /* 10 T_TRCTRAP */ "", /* 11 unused */ "page fault", /* 12 T_PAGEFLT */ "", /* 13 unused */ "alignment fault", /* 14 T_ALIGNFLT */ "", /* 15 unused */ "", /* 16 unused */ "", /* 17 unused */ "integer divide fault", /* 18 T_DIVIDE */ "non-maskable interrupt trap", /* 19 T_NMI */ "overflow trap", /* 20 T_OFLOW */ "FPU bounds check fault", /* 21 T_BOUND */ "FPU device not available", /* 22 T_DNA */ "double fault", /* 23 T_DOUBLEFLT */ "FPU operand fetch fault", /* 24 T_FPOPFLT */ "invalid TSS fault", /* 25 T_TSSFLT */ "segment not present fault", /* 26 T_SEGNPFLT */ "stack fault", /* 27 T_STKFLT */ "machine check trap", /* 28 T_MCHK */ "SIMD floating-point exception", /* 29 T_XMMFLT */ "reserved (unknown) fault", /* 30 T_RESERVED */ }; #if defined(I586_CPU) && !defined(NO_F00F_HACK) extern int has_f00f_bug; #endif #ifdef KDB static int kdb_on_nmi = 1; SYSCTL_INT(_machdep, OID_AUTO, kdb_on_nmi, CTLFLAG_RW, &kdb_on_nmi, 0, "Go to KDB on NMI"); #endif static int panic_on_nmi = 1; SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW, &panic_on_nmi, 0, "Panic on NMI"); static int prot_fault_translation = 0; SYSCTL_INT(_machdep, OID_AUTO, prot_fault_translation, CTLFLAG_RW, &prot_fault_translation, 0, "Select signal to deliver on protection fault"); extern char *syscallnames[]; /* * Exception, fault, and trap interface to the FreeBSD kernel. * This common code is called from assembly language IDT gate entry * routines that prepare a suitable stack frame, and restore this * frame after the exception has been processed. */ void trap(struct trapframe *frame) { struct thread *td = curthread; struct proc *p = td->td_proc; int i = 0, ucode = 0, code; u_int type; register_t addr = 0; vm_offset_t eva; ksiginfo_t ksi; #ifdef POWERFAIL_NMI static int lastalert = 0; #endif PCPU_INC(cnt.v_trap); type = frame->tf_trapno; #ifdef SMP #ifdef STOP_NMI /* Handler for NMI IPIs used for stopping CPUs. */ if (type == T_NMI) { if (ipi_nmi_handler() == 0) goto out; } #endif /* STOP_NMI */ #endif /* SMP */ #ifdef KDB if (kdb_active) { kdb_reenter(); goto out; } #endif #ifdef HWPMC_HOOKS /* * CPU PMCs interrupt using an NMI so we check for that first. * If the HWPMC module is active, 'pmc_hook' will point to * the function to be called. A return value of '1' from the * hook means that the NMI was handled by it and that we can * return immediately. */ if (type == T_NMI && pmc_intr && (*pmc_intr)(PCPU_GET(cpuid), frame)) goto out; #endif #ifdef KDTRACE_HOOKS /* * A trap can occur while DTrace executes a probe. Before * executing the probe, DTrace blocks re-scheduling and sets * a flag in it's per-cpu flags to indicate that it doesn't * want to fault. On returning from the the probe, the no-fault * flag is cleared and finally re-scheduling is enabled. * * If the DTrace kernel module has registered a trap handler, * call it and if it returns non-zero, assume that it has * handled the trap and modified the trap frame so that this * function can return normally. */ if ((type == T_PROTFLT || type == T_PAGEFLT) && dtrace_trap_func != NULL) if ((*dtrace_trap_func)(frame, type)) goto out; #endif if ((frame->tf_eflags & PSL_I) == 0) { /* * Buggy application or kernel code has disabled * interrupts and then trapped. Enabling interrupts * now is wrong, but it is better than running with * interrupts disabled until they are accidentally * enabled later. */ if (ISPL(frame->tf_cs) == SEL_UPL || (frame->tf_eflags & PSL_VM)) printf( "pid %ld (%s): trap %d with interrupts disabled\n", (long)curproc->p_pid, curthread->td_name, type); else if (type != T_BPTFLT && type != T_TRCTRAP && frame->tf_eip != (int)cpu_switch_load_gs) { /* * XXX not quite right, since this may be for a * multiple fault in user mode. */ printf("kernel trap %d with interrupts disabled\n", type); /* * Page faults need interrupts disabled until later, * and we shouldn't enable interrupts while holding * a spin lock or if servicing an NMI. */ if (type != T_NMI && type != T_PAGEFLT && td->td_md.md_spinlock_count == 0) enable_intr(); } } eva = 0; code = frame->tf_err; if (type == T_PAGEFLT) { /* * For some Cyrix CPUs, %cr2 is clobbered by * interrupts. This problem is worked around by using * an interrupt gate for the pagefault handler. We * are finally ready to read %cr2 and then must * reenable interrupts. * * If we get a page fault while in a critical section, then * it is most likely a fatal kernel page fault. The kernel * is already going to panic trying to get a sleep lock to * do the VM lookup, so just consider it a fatal trap so the * kernel can print out a useful trap message and even get * to the debugger. * * If we get a page fault while holding a non-sleepable * lock, then it is most likely a fatal kernel page fault. * If WITNESS is enabled, then it's going to whine about * bogus LORs with various VM locks, so just skip to the * fatal trap handling directly. */ eva = rcr2(); if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK | WARN_GIANTOK, NULL, "Kernel page fault") != 0) trap_fatal(frame, eva); else enable_intr(); } if ((ISPL(frame->tf_cs) == SEL_UPL) || ((frame->tf_eflags & PSL_VM) && !(PCPU_GET(curpcb)->pcb_flags & PCB_VM86CALL))) { /* user trap */ td->td_pticks = 0; td->td_frame = frame; addr = frame->tf_eip; if (td->td_ucred != p->p_ucred) cred_update_thread(td); switch (type) { case T_PRIVINFLT: /* privileged instruction fault */ i = SIGILL; ucode = ILL_PRVOPC; break; case T_BPTFLT: /* bpt instruction fault */ case T_TRCTRAP: /* trace trap */ enable_intr(); frame->tf_eflags &= ~PSL_T; i = SIGTRAP; ucode = (type == T_TRCTRAP ? TRAP_TRACE : TRAP_BRKPT); break; case T_ARITHTRAP: /* arithmetic trap */ #ifdef DEV_NPX ucode = npxtrap(); if (ucode == -1) goto userout; #else ucode = 0; #endif i = SIGFPE; break; /* * The following two traps can happen in * vm86 mode, and, if so, we want to handle * them specially. */ case T_PROTFLT: /* general protection fault */ case T_STKFLT: /* stack fault */ if (frame->tf_eflags & PSL_VM) { i = vm86_emulate((struct vm86frame *)frame); if (i == 0) goto user; break; } i = SIGBUS; ucode = (type == T_PROTFLT) ? BUS_OBJERR : BUS_ADRERR; break; case T_SEGNPFLT: /* segment not present fault */ i = SIGBUS; ucode = BUS_ADRERR; break; case T_TSSFLT: /* invalid TSS fault */ i = SIGBUS; ucode = BUS_OBJERR; break; case T_DOUBLEFLT: /* double fault */ default: i = SIGBUS; ucode = BUS_OBJERR; break; case T_PAGEFLT: /* page fault */ i = trap_pfault(frame, TRUE, eva); #if defined(I586_CPU) && !defined(NO_F00F_HACK) if (i == -2) { /* * The f00f hack workaround has triggered, so * treat the fault as an illegal instruction * (T_PRIVINFLT) instead of a page fault. */ type = frame->tf_trapno = T_PRIVINFLT; /* Proceed as in that case. */ ucode = ILL_PRVOPC; i = SIGILL; break; } #endif if (i == -1) goto userout; if (i == 0) goto user; if (i == SIGSEGV) ucode = SEGV_MAPERR; else { if (prot_fault_translation == 0) { /* * Autodetect. * This check also covers the images * without the ABI-tag ELF note. */ if (p->p_osrel >= 700004) { i = SIGSEGV; ucode = SEGV_ACCERR; } else { i = SIGBUS; ucode = BUS_PAGE_FAULT; } } else if (prot_fault_translation == 1) { /* * Always compat mode. */ i = SIGBUS; ucode = BUS_PAGE_FAULT; } else { /* * Always SIGSEGV mode. */ i = SIGSEGV; ucode = SEGV_ACCERR; } } addr = eva; break; case T_DIVIDE: /* integer divide fault */ ucode = FPE_INTDIV; i = SIGFPE; break; #ifdef DEV_ISA case T_NMI: #ifdef POWERFAIL_NMI #ifndef TIMER_FREQ # define TIMER_FREQ 1193182 #endif if (time_second - lastalert > 10) { log(LOG_WARNING, "NMI: power fail\n"); sysbeep(880, hz); lastalert = time_second; } goto userout; #else /* !POWERFAIL_NMI */ /* machine/parity/power fail/"kitchen sink" faults */ - /* XXX Giant */ if (isa_nmi(code) == 0) { #ifdef KDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (kdb_on_nmi) { printf ("NMI ... going to debugger\n"); kdb_trap(type, 0, frame); } #endif /* KDB */ goto userout; } else if (panic_on_nmi) panic("NMI indicates hardware failure"); break; #endif /* POWERFAIL_NMI */ #endif /* DEV_ISA */ case T_OFLOW: /* integer overflow fault */ ucode = FPE_INTOVF; i = SIGFPE; break; case T_BOUND: /* bounds check fault */ ucode = FPE_FLTSUB; i = SIGFPE; break; case T_DNA: #ifdef DEV_NPX /* transparent fault (due to context switch "late") */ if (npxdna()) goto userout; #endif printf("pid %d killed due to lack of floating point\n", p->p_pid); i = SIGKILL; ucode = 0; break; case T_FPOPFLT: /* FPU operand fetch fault */ ucode = ILL_COPROC; i = SIGILL; break; case T_XMMFLT: /* SIMD floating-point exception */ ucode = 0; /* XXX */ i = SIGFPE; break; } } else { /* kernel trap */ KASSERT(cold || td->td_ucred != NULL, ("kernel trap doesn't have ucred")); switch (type) { case T_PAGEFLT: /* page fault */ (void) trap_pfault(frame, FALSE, eva); goto out; case T_DNA: #ifdef DEV_NPX /* * The kernel is apparently using npx for copying. * XXX this should be fatal unless the kernel has * registered such use. */ if (npxdna()) goto out; #endif break; /* * The following two traps can happen in * vm86 mode, and, if so, we want to handle * them specially. */ case T_PROTFLT: /* general protection fault */ case T_STKFLT: /* stack fault */ if (frame->tf_eflags & PSL_VM) { i = vm86_emulate((struct vm86frame *)frame); if (i != 0) /* * returns to original process */ vm86_trap((struct vm86frame *)frame); goto out; } if (type == T_STKFLT) break; /* FALL THROUGH */ case T_SEGNPFLT: /* segment not present fault */ if (PCPU_GET(curpcb)->pcb_flags & PCB_VM86CALL) break; /* * Invalid %fs's and %gs's can be created using * procfs or PT_SETREGS or by invalidating the * underlying LDT entry. This causes a fault * in kernel mode when the kernel attempts to * switch contexts. Lose the bad context * (XXX) so that we can continue, and generate * a signal. */ if (frame->tf_eip == (int)cpu_switch_load_gs) { PCPU_GET(curpcb)->pcb_gs = 0; #if 0 PROC_LOCK(p); psignal(p, SIGBUS); PROC_UNLOCK(p); #endif goto out; } if (td->td_intr_nesting_level != 0) break; /* * Invalid segment selectors and out of bounds * %eip's and %esp's can be set up in user mode. * This causes a fault in kernel mode when the * kernel tries to return to user mode. We want * to get this fault so that we can fix the * problem here and not have to check all the * selectors and pointers when the user changes * them. */ if (frame->tf_eip == (int)doreti_iret) { frame->tf_eip = (int)doreti_iret_fault; goto out; } if (frame->tf_eip == (int)doreti_popl_ds) { frame->tf_eip = (int)doreti_popl_ds_fault; goto out; } if (frame->tf_eip == (int)doreti_popl_es) { frame->tf_eip = (int)doreti_popl_es_fault; goto out; } if (frame->tf_eip == (int)doreti_popl_fs) { frame->tf_eip = (int)doreti_popl_fs_fault; goto out; } if (PCPU_GET(curpcb)->pcb_onfault != NULL) { frame->tf_eip = (int)PCPU_GET(curpcb)->pcb_onfault; goto out; } break; case T_TSSFLT: /* * PSL_NT can be set in user mode and isn't cleared * automatically when the kernel is entered. This * causes a TSS fault when the kernel attempts to * `iret' because the TSS link is uninitialized. We * want to get this fault so that we can fix the * problem here and not every time the kernel is * entered. */ if (frame->tf_eflags & PSL_NT) { frame->tf_eflags &= ~PSL_NT; goto out; } break; case T_TRCTRAP: /* trace trap */ if (frame->tf_eip == (int)IDTVEC(lcall_syscall)) { /* * We've just entered system mode via the * syscall lcall. Continue single stepping * silently until the syscall handler has * saved the flags. */ goto out; } if (frame->tf_eip == (int)IDTVEC(lcall_syscall) + 1) { /* * The syscall handler has now saved the * flags. Stop single stepping it. */ frame->tf_eflags &= ~PSL_T; goto out; } /* * Ignore debug register trace traps due to * accesses in the user's address space, which * can happen under several conditions such as * if a user sets a watchpoint on a buffer and * then passes that buffer to a system call. * We still want to get TRCTRAPS for addresses * in kernel space because that is useful when * debugging the kernel. */ - /* XXX Giant */ if (user_dbreg_trap() && !(PCPU_GET(curpcb)->pcb_flags & PCB_VM86CALL)) { /* * Reset breakpoint bits because the * processor doesn't */ load_dr6(rdr6() & 0xfffffff0); goto out; } /* * FALLTHROUGH (TRCTRAP kernel mode, kernel address) */ case T_BPTFLT: /* * If KDB is enabled, let it handle the debugger trap. * Otherwise, debugger traps "can't happen". */ #ifdef KDB if (kdb_trap(type, 0, frame)) goto out; #endif break; #ifdef DEV_ISA case T_NMI: #ifdef POWERFAIL_NMI if (time_second - lastalert > 10) { log(LOG_WARNING, "NMI: power fail\n"); sysbeep(880, hz); lastalert = time_second; } goto out; #else /* !POWERFAIL_NMI */ - /* XXX Giant */ /* machine/parity/power fail/"kitchen sink" faults */ if (isa_nmi(code) == 0) { #ifdef KDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (kdb_on_nmi) { printf ("NMI ... going to debugger\n"); kdb_trap(type, 0, frame); } #endif /* KDB */ goto out; } else if (panic_on_nmi == 0) goto out; /* FALLTHROUGH */ #endif /* POWERFAIL_NMI */ #endif /* DEV_ISA */ } trap_fatal(frame, eva); goto out; } /* Translate fault for emulators (e.g. Linux) */ if (*p->p_sysent->sv_transtrap) i = (*p->p_sysent->sv_transtrap)(i, type); ksiginfo_init_trap(&ksi); ksi.ksi_signo = i; ksi.ksi_code = ucode; ksi.ksi_addr = (void *)addr; ksi.ksi_trapno = type; trapsignal(td, &ksi); #ifdef DEBUG if (type <= MAX_TRAP_MSG) { uprintf("fatal process exception: %s", trap_msg[type]); if ((type == T_PAGEFLT) || (type == T_PROTFLT)) uprintf(", fault VA = 0x%lx", (u_long)eva); uprintf("\n"); } #endif user: userret(td, frame); mtx_assert(&Giant, MA_NOTOWNED); userout: out: return; } static int trap_pfault(frame, usermode, eva) struct trapframe *frame; int usermode; vm_offset_t eva; { vm_offset_t va; struct vmspace *vm = NULL; vm_map_t map; int rv = 0; vm_prot_t ftype; struct thread *td = curthread; struct proc *p = td->td_proc; va = trunc_page(eva); if (va >= KERNBASE) { /* * Don't allow user-mode faults in kernel address space. * An exception: if the faulting address is the invalid * instruction entry in the IDT, then the Intel Pentium * F00F bug workaround was triggered, and we need to * treat it is as an illegal instruction, and not a page * fault. */ #if defined(I586_CPU) && !defined(NO_F00F_HACK) if ((eva == (unsigned int)&idt[6]) && has_f00f_bug) return -2; #endif if (usermode) goto nogo; map = kernel_map; } else { /* * This is a fault on non-kernel virtual memory. * vm is initialized above to NULL. If curproc is NULL * or curproc->p_vmspace is NULL the fault is fatal. */ if (p != NULL) vm = p->p_vmspace; if (vm == NULL) goto nogo; map = &vm->vm_map; } /* * PGEX_I is defined only if the execute disable bit capability is * supported and enabled. */ if (frame->tf_err & PGEX_W) ftype = VM_PROT_WRITE; #ifdef PAE else if ((frame->tf_err & PGEX_I) && pg_nx != 0) ftype = VM_PROT_EXECUTE; #endif else ftype = VM_PROT_READ; if (map != kernel_map) { /* * Keep swapout from messing with us during this * critical time. */ PROC_LOCK(p); ++p->p_lock; PROC_UNLOCK(p); /* Fault in the user page: */ rv = vm_fault(map, va, ftype, (ftype & VM_PROT_WRITE) ? VM_FAULT_DIRTY : VM_FAULT_NORMAL); PROC_LOCK(p); --p->p_lock; PROC_UNLOCK(p); } else { /* * Don't have to worry about process locking or stacks in the * kernel. */ rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL); } if (rv == KERN_SUCCESS) return (0); nogo: if (!usermode) { if (td->td_intr_nesting_level == 0 && PCPU_GET(curpcb)->pcb_onfault != NULL) { frame->tf_eip = (int)PCPU_GET(curpcb)->pcb_onfault; return (0); } trap_fatal(frame, eva); return (-1); } return((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV); } static void trap_fatal(frame, eva) struct trapframe *frame; vm_offset_t eva; { int code, ss, esp; u_int type; struct soft_segment_descriptor softseg; char *msg; code = frame->tf_err; type = frame->tf_trapno; sdtossd(&gdt[IDXSEL(frame->tf_cs & 0xffff)].sd, &softseg); if (type <= MAX_TRAP_MSG) msg = trap_msg[type]; else msg = "UNKNOWN"; printf("\n\nFatal trap %d: %s while in %s mode\n", type, msg, frame->tf_eflags & PSL_VM ? "vm86" : ISPL(frame->tf_cs) == SEL_UPL ? "user" : "kernel"); #ifdef SMP /* two separate prints in case of a trap on an unmapped page */ printf("cpuid = %d; ", PCPU_GET(cpuid)); printf("apic id = %02x\n", PCPU_GET(apic_id)); #endif if (type == T_PAGEFLT) { printf("fault virtual address = 0x%x\n", eva); printf("fault code = %s %s, %s\n", code & PGEX_U ? "user" : "supervisor", code & PGEX_W ? "write" : "read", code & PGEX_P ? "protection violation" : "page not present"); } printf("instruction pointer = 0x%x:0x%x\n", frame->tf_cs & 0xffff, frame->tf_eip); if ((ISPL(frame->tf_cs) == SEL_UPL) || (frame->tf_eflags & PSL_VM)) { ss = frame->tf_ss & 0xffff; esp = frame->tf_esp; } else { ss = GSEL(GDATA_SEL, SEL_KPL); esp = (int)&frame->tf_esp; } printf("stack pointer = 0x%x:0x%x\n", ss, esp); printf("frame pointer = 0x%x:0x%x\n", ss, frame->tf_ebp); printf("code segment = base 0x%x, limit 0x%x, type 0x%x\n", softseg.ssd_base, softseg.ssd_limit, softseg.ssd_type); printf(" = DPL %d, pres %d, def32 %d, gran %d\n", softseg.ssd_dpl, softseg.ssd_p, softseg.ssd_def32, softseg.ssd_gran); printf("processor eflags = "); if (frame->tf_eflags & PSL_T) printf("trace trap, "); if (frame->tf_eflags & PSL_I) printf("interrupt enabled, "); if (frame->tf_eflags & PSL_NT) printf("nested task, "); if (frame->tf_eflags & PSL_RF) printf("resume, "); if (frame->tf_eflags & PSL_VM) printf("vm86, "); printf("IOPL = %d\n", (frame->tf_eflags & PSL_IOPL) >> 12); printf("current process = "); if (curproc) { printf("%lu (%s)\n", (u_long)curproc->p_pid, curthread->td_name); } else { printf("Idle\n"); } #ifdef KDB if (debugger_on_panic || kdb_active) { frame->tf_err = eva; /* smuggle fault address to ddb */ if (kdb_trap(type, 0, frame)) { frame->tf_err = code; /* restore error code */ return; } frame->tf_err = code; /* restore error code */ } #endif printf("trap number = %d\n", type); if (type <= MAX_TRAP_MSG) panic("%s", trap_msg[type]); else panic("unknown/reserved trap"); } /* * Double fault handler. Called when a fault occurs while writing * a frame for a trap/exception onto the stack. This usually occurs * when the stack overflows (such is the case with infinite recursion, * for example). * * XXX Note that the current PTD gets replaced by IdlePTD when the * task switch occurs. This means that the stack that was active at * the time of the double fault is not available at unless * the machine was idle when the double fault occurred. The downside * of this is that "trace " in ddb won't work. */ void dblfault_handler() { #ifdef KDTRACE_HOOKS if (dtrace_doubletrap_func != NULL) (*dtrace_doubletrap_func)(); #endif printf("\nFatal double fault:\n"); printf("eip = 0x%x\n", PCPU_GET(common_tss.tss_eip)); printf("esp = 0x%x\n", PCPU_GET(common_tss.tss_esp)); printf("ebp = 0x%x\n", PCPU_GET(common_tss.tss_ebp)); #ifdef SMP /* two separate prints in case of a trap on an unmapped page */ printf("cpuid = %d; ", PCPU_GET(cpuid)); printf("apic id = %02x\n", PCPU_GET(apic_id)); #endif panic("double fault"); } /* * syscall - system call request C handler * * A system call is essentially treated as a trap. */ void syscall(struct trapframe *frame) { caddr_t params; struct sysent *callp; struct thread *td = curthread; struct proc *p = td->td_proc; register_t orig_tf_eflags; int error; int narg; int args[8]; u_int code; ksiginfo_t ksi; PCPU_INC(cnt.v_syscall); #ifdef DIAGNOSTIC if (ISPL(frame->tf_cs) != SEL_UPL) { panic("syscall"); /* NOT REACHED */ } #endif td->td_pticks = 0; td->td_frame = frame; if (td->td_ucred != p->p_ucred) cred_update_thread(td); params = (caddr_t)frame->tf_esp + sizeof(int); code = frame->tf_eax; orig_tf_eflags = frame->tf_eflags; if (p->p_sysent->sv_prepsyscall) { - /* - * The prep code is MP aware. - */ (*p->p_sysent->sv_prepsyscall)(frame, args, &code, ¶ms); } else { /* * Need to check if this is a 32 bit or 64 bit syscall. - * fuword is MP aware. */ if (code == SYS_syscall) { /* * Code is first argument, followed by actual args. */ code = fuword(params); params += sizeof(int); } else if (code == SYS___syscall) { /* * Like syscall, but code is a quad, so as to maintain * quad alignment for the rest of the arguments. */ code = fuword(params); params += sizeof(quad_t); } } if (p->p_sysent->sv_mask) code &= p->p_sysent->sv_mask; if (code >= p->p_sysent->sv_size) callp = &p->p_sysent->sv_table[0]; else callp = &p->p_sysent->sv_table[code]; narg = callp->sy_narg; - /* - * copyin and the ktrsyscall()/ktrsysret() code is MP-aware - */ if (params != NULL && narg != 0) error = copyin(params, (caddr_t)args, (u_int)(narg * sizeof(int))); else error = 0; #ifdef KTRACE if (KTRPOINT(td, KTR_SYSCALL)) ktrsyscall(code, narg, args); #endif CTR4(KTR_SYSC, "syscall enter thread %p pid %d proc %s code %d", td, td->td_proc->p_pid, td->td_name, code); td->td_syscalls++; if (error == 0) { td->td_retval[0] = 0; td->td_retval[1] = frame->tf_edx; STOPEVENT(p, S_SCE, narg); PTRACESTOP_SC(p, td, S_PT_SCE); #ifdef KDTRACE_HOOKS /* * If the systrace module has registered it's probe * callback and if there is a probe active for the * syscall 'entry', process the probe. */ if (systrace_probe_func != NULL && callp->sy_entry != 0) (*systrace_probe_func)(callp->sy_entry, code, callp, args); #endif AUDIT_SYSCALL_ENTER(code, td); error = (*callp->sy_call)(td, args); AUDIT_SYSCALL_EXIT(error, td); /* Save the latest error return value. */ td->td_errno = error; #ifdef KDTRACE_HOOKS /* * If the systrace module has registered it's probe * callback and if there is a probe active for the * syscall 'return', process the probe. */ if (systrace_probe_func != NULL && callp->sy_return != 0) (*systrace_probe_func)(callp->sy_return, code, callp, args); #endif } switch (error) { case 0: frame->tf_eax = td->td_retval[0]; frame->tf_edx = td->td_retval[1]; frame->tf_eflags &= ~PSL_C; break; case ERESTART: /* * Reconstruct pc, assuming lcall $X,y is 7 bytes, * int 0x80 is 2 bytes. We saved this in tf_err. */ frame->tf_eip -= frame->tf_err; break; case EJUSTRETURN: break; default: if (p->p_sysent->sv_errsize) { if (error >= p->p_sysent->sv_errsize) error = -1; /* XXX */ else error = p->p_sysent->sv_errtbl[error]; } frame->tf_eax = error; frame->tf_eflags |= PSL_C; break; } /* * Traced syscall. */ if ((orig_tf_eflags & PSL_T) && !(orig_tf_eflags & PSL_VM)) { frame->tf_eflags &= ~PSL_T; ksiginfo_init_trap(&ksi); ksi.ksi_signo = SIGTRAP; ksi.ksi_code = TRAP_TRACE; ksi.ksi_addr = (void *)frame->tf_eip; trapsignal(td, &ksi); } /* * Check for misbehavior. */ WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning", (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"); KASSERT(td->td_critnest == 0, ("System call %s returning in a critical section", (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???")); KASSERT(td->td_locks == 0, ("System call %s returning with %d locks held", (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???", td->td_locks)); /* * Handle reschedule and other end-of-syscall issues */ userret(td, frame); CTR4(KTR_SYSC, "syscall exit thread %p pid %d proc %s code %d", td, td->td_proc->p_pid, td->td_name, code); #ifdef KTRACE if (KTRPOINT(td, KTR_SYSRET)) ktrsysret(code, error, td->td_retval[0]); #endif /* * This works because errno is findable through the * register set. If we ever support an emulation where this * is not the case, this code will need to be revisited. */ STOPEVENT(p, S_SCX, code); PTRACESTOP_SC(p, td, S_PT_SCX); }