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 /* Handler for NMI IPIs used for stopping CPUs. */ if (type == T_NMI) { if (ipi_nmi_handler() == 0) goto out; } #endif /* SMP */ #ifdef KDB if (kdb_active) { kdb_reenter(); goto out; } #endif if (type == T_RESERVED) { trap_fatal(frame, 0); goto out; } #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 if (type == T_MCHK) { if (!mca_intr()) trap_fatal(frame, 0); goto out; } #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 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; if (type == T_DTRACE_PROBE || type == T_DTRACE_RET || type == T_BPTFLT) { struct reg regs; fill_frame_regs(frame, ®s); if (type == T_DTRACE_PROBE && dtrace_fasttrap_probe_ptr != NULL && dtrace_fasttrap_probe_ptr(®s) == 0) goto out; if (type == T_BPTFLT && dtrace_pid_probe_ptr != NULL && dtrace_pid_probe_ptr(®s) == 0) goto out; if (type == T_DTRACE_RET && dtrace_return_probe_ptr != NULL && dtrace_return_probe_ptr(®s) == 0) 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)) uprintf( "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 (SV_CURPROC_ABI() == SV_ABI_FREEBSD && p->p_osrel >= P_OSREL_SIGSEGV) { 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 */ 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 KASSERT(PCB_USER_FPU(td->td_pcb), ("kernel FPU ctx has leaked")); /* transparent fault (due to context switch "late") */ if (npxdna()) goto userout; #endif uprintf("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 KASSERT(!PCB_USER_FPU(td->td_pcb), ("Unregistered use of FPU in kernel")); if (npxdna()) goto out; #endif break; case T_ARITHTRAP: /* arithmetic trap */ case T_XMMFLT: /* SIMD floating-point exception */ case T_FPOPFLT: /* FPU operand fetch fault */ /* * XXXKIB for now disable any FPU traps in kernel * handler registration seems to be overkill */ trap_fatal(frame, 0); goto out; /* * 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); kern_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. */ 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 */ /* 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); KASSERT(PCB_USER_FPU(td->td_pcb), ("Return from trap with kernel FPU ctx leaked")); userout: out: return; }
/* * Exception, fault, and trap interface to the 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. * * This function is also called from doreti in an interlock to handle ASTs. * For example: hardwareint->INTROUTINE->(set ast)->doreti->trap * * NOTE! We have to retrieve the fault address prior to potentially * blocking, including blocking on any token. * * NOTE! NMI and kernel DBG traps remain on their respective pcpu IST * stacks if taken from a kernel RPL. trap() cannot block in this * situation. DDB entry or a direct report-and-return is ok. * * XXX gd_trap_nesting_level currently prevents lwkt_switch() from panicing * if an attempt is made to switch from a fast interrupt or IPI. */ void trap(struct trapframe *frame) { static struct krate sscpubugrate = { 1 }; struct globaldata *gd = mycpu; struct thread *td = gd->gd_curthread; struct lwp *lp = td->td_lwp; struct proc *p; int sticks = 0; int i = 0, ucode = 0, type, code; #ifdef INVARIANTS int crit_count = td->td_critcount; lwkt_tokref_t curstop = td->td_toks_stop; #endif vm_offset_t eva; p = td->td_proc; clear_quickret(); #ifdef DDB /* * We need to allow T_DNA faults when the debugger is active since * some dumping paths do large bcopy() which use the floating * point registers for faster copying. */ if (db_active && frame->tf_trapno != T_DNA) { eva = (frame->tf_trapno == T_PAGEFLT ? frame->tf_addr : 0); ++gd->gd_trap_nesting_level; trap_fatal(frame, eva); --gd->gd_trap_nesting_level; goto out2; } #endif eva = 0; 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. */ type = frame->tf_trapno; if (ISPL(frame->tf_cs) == SEL_UPL) { /* JG curproc can be NULL */ kprintf( "pid %ld (%s): trap %d with interrupts disabled\n", (long)curproc->p_pid, curproc->p_comm, type); } else if ((type == T_STKFLT || type == T_PROTFLT || type == T_SEGNPFLT) && frame->tf_rip == (long)doreti_iret) { /* * iretq fault from kernel mode during return to * userland. * * This situation is expected, don't complain. */ } 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. */ kprintf("kernel trap %d (%s @ 0x%016jx) with " "interrupts disabled\n", type, td->td_comm, frame->tf_rip); } cpu_enable_intr(); } type = frame->tf_trapno; code = frame->tf_err; if (ISPL(frame->tf_cs) == SEL_UPL) { /* user trap */ KTR_LOG(kernentry_trap, p->p_pid, lp->lwp_tid, frame->tf_trapno, eva); userenter(td, p); sticks = (int)td->td_sticks; KASSERT(lp->lwp_md.md_regs == frame, ("Frame mismatch %p %p", lp->lwp_md.md_regs, frame)); 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 */ frame->tf_rflags &= ~PSL_T; i = SIGTRAP; ucode = (type == T_TRCTRAP ? TRAP_TRACE : TRAP_BRKPT); break; case T_ARITHTRAP: /* arithmetic trap */ ucode = code; i = SIGFPE; break; case T_ASTFLT: /* Allow process switch */ mycpu->gd_cnt.v_soft++; if (mycpu->gd_reqflags & RQF_AST_OWEUPC) { atomic_clear_int(&mycpu->gd_reqflags, RQF_AST_OWEUPC); addupc_task(p, p->p_prof.pr_addr, p->p_prof.pr_ticks); } goto out; 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 */ case T_DOUBLEFLT: /* double fault */ default: i = SIGBUS; ucode = BUS_OBJERR; break; case T_PAGEFLT: /* page fault */ i = trap_pfault(frame, TRUE); #ifdef DDB if (frame->tf_rip == 0) { /* used for kernel debugging only */ while (freeze_on_seg_fault) tsleep(p, 0, "freeze", hz * 20); } #endif if (i == -1 || i == 0) goto out; if (i == SIGSEGV) { ucode = SEGV_MAPERR; } else { i = SIGSEGV; ucode = SEGV_ACCERR; } break; case T_DIVIDE: /* integer divide fault */ ucode = FPE_INTDIV; i = SIGFPE; break; #if NISA > 0 case T_NMI: /* machine/parity/power fail/"kitchen sink" faults */ if (isa_nmi(code) == 0) { #ifdef DDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (ddb_on_nmi) { kprintf ("NMI ... going to debugger\n"); kdb_trap(type, 0, frame); } #endif /* DDB */ goto out2; } else if (panic_on_nmi) panic("NMI indicates hardware failure"); break; #endif /* NISA > 0 */ 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: /* * Virtual kernel intercept - pass the DNA exception * to the virtual kernel if it asked to handle it. * This occurs when the virtual kernel is holding * onto the FP context for a different emulated * process then the one currently running. * * We must still call npxdna() since we may have * saved FP state that the virtual kernel needs * to hand over to a different emulated process. */ if (lp->lwp_vkernel && lp->lwp_vkernel->ve && (td->td_pcb->pcb_flags & FP_VIRTFP) ) { npxdna(); break; } /* * The kernel may have switched out the FP unit's * state, causing the user process to take a fault * when it tries to use the FP unit. Restore the * state here */ if (npxdna()) { gd->gd_cnt.v_trap++; goto out; } i = SIGFPE; ucode = FPE_FPU_NP_TRAP; 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 */ switch (type) { case T_PAGEFLT: /* page fault */ trap_pfault(frame, FALSE); goto out2; case T_DNA: /* * The kernel is apparently using fpu for copying. * XXX this should be fatal unless the kernel has * registered such use. */ if (npxdna()) { gd->gd_cnt.v_trap++; goto out2; } break; case T_STKFLT: /* stack fault */ case T_PROTFLT: /* general protection fault */ case T_SEGNPFLT: /* segment not present fault */ /* * 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 (mycpu->gd_intr_nesting_level == 0) { /* * NOTE: in 64-bit mode traps push rsp/ss * even if no ring change occurs. */ if (td->td_pcb->pcb_onfault && td->td_pcb->pcb_onfault_sp == frame->tf_rsp) { frame->tf_rip = (register_t) td->td_pcb->pcb_onfault; goto out2; } /* * If the iretq in doreti faults during * return to user, it will be special-cased * in IDTVEC(prot) to get here. We want * to 'return' to doreti_iret_fault in * ipl.s in approximately the same state we * were in at the iretq. */ if (frame->tf_rip == (long)doreti_iret) { frame->tf_rip = (long)doreti_iret_fault; goto out2; } } 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; #if 0 /* do we need this? */ if (frame->tf_rip == (long)doreti_iret) frame->tf_rip = (long)doreti_iret_fault; #endif goto out2; } break; case T_TRCTRAP: /* trace trap */ /* * Detect historical CPU artifact on syscall or int $3 * entry (if not shortcutted in exception.s via * DIRECT_DISALLOW_SS_CPUBUG). */ gd->gd_cnt.v_trap++; if (frame->tf_rip == (register_t)IDTVEC(fast_syscall)) { krateprintf(&sscpubugrate, "Caught #DB at syscall cpu artifact\n"); goto out2; } if (frame->tf_rip == (register_t)IDTVEC(bpt)) { krateprintf(&sscpubugrate, "Caught #DB at int $N cpu artifact\n"); goto out2; } /* * 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 */ load_dr6(rdr6() & ~0xf); goto out2; } /* * FALLTHROUGH (TRCTRAP kernel mode, kernel address) */ case T_BPTFLT: /* * If DDB is enabled, let it handle the debugger trap. * Otherwise, debugger traps "can't happen". */ ucode = TRAP_BRKPT; #ifdef DDB if (kdb_trap(type, 0, frame)) goto out2; #endif break; #if NISA > 0 case T_NMI: /* machine/parity/power fail/"kitchen sink" faults */ if (isa_nmi(code) == 0) { #ifdef DDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (ddb_on_nmi) { kprintf ("NMI ... going to debugger\n"); kdb_trap(type, 0, frame); } #endif /* DDB */ goto out2; } else if (panic_on_nmi == 0) goto out2; /* FALL THROUGH */ #endif /* NISA > 0 */ } trap_fatal(frame, 0); goto out2; } /* * Fault from user mode, virtual kernel interecept. * * If the fault is directly related to a VM context managed by a * virtual kernel then let the virtual kernel handle it. */ if (lp->lwp_vkernel && lp->lwp_vkernel->ve) { vkernel_trap(lp, frame); goto out; } /* Translate fault for emulators (e.g. Linux) */ if (*p->p_sysent->sv_transtrap) i = (*p->p_sysent->sv_transtrap)(i, type); gd->gd_cnt.v_trap++; trapsignal(lp, i, ucode); #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 out: userret(lp, frame, sticks); userexit(lp); out2: ; if (p != NULL && lp != NULL) KTR_LOG(kernentry_trap_ret, p->p_pid, lp->lwp_tid); #ifdef INVARIANTS KASSERT(crit_count == td->td_critcount, ("trap: critical section count mismatch! %d/%d", crit_count, td->td_pri)); KASSERT(curstop == td->td_toks_stop, ("trap: extra tokens held after trap! %ld/%ld", curstop - &td->td_toks_base, td->td_toks_stop - &td->td_toks_base)); #endif }
void kern_trap(struct trapframe *frame) { struct globaldata *gd = mycpu; struct thread *td = gd->gd_curthread; struct lwp *lp; struct proc *p; int i = 0, ucode = 0, type, code; int have_mplock = 0; #ifdef INVARIANTS int crit_count = td->td_critcount; lwkt_tokref_t curstop = td->td_toks_stop; #endif vm_offset_t eva; lp = td->td_lwp; p = td->td_proc; if (frame->tf_trapno == T_PAGEFLT) eva = frame->tf_err; else eva = 0; #ifdef DDB if (db_active) { ++gd->gd_trap_nesting_level; MAKEMPSAFE(have_mplock); trap_fatal(frame, FALSE, eva); --gd->gd_trap_nesting_level; goto out2; } #endif type = frame->tf_trapno; code = frame->tf_err; #if 0 kernel_trap: #endif /* kernel trap */ switch (type) { case T_PAGEFLT: /* page fault */ MAKEMPSAFE(have_mplock); trap_pfault(frame, FALSE, eva); goto out2; case T_DNA: #if NNPX > 0 /* * The kernel may be using npx for copying or other * purposes. */ panic("kernel NPX should not happen"); if (npxdna(frame)) goto out2; #endif break; case T_PROTFLT: /* general protection fault */ case T_SEGNPFLT: /* segment not present fault */ /* * 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 (mycpu->gd_intr_nesting_level == 0) { if (td->td_pcb->pcb_onfault) { frame->tf_eip = (register_t)td->td_pcb->pcb_onfault; goto out2; } } 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 out2; } break; case T_TRCTRAP: /* trace trap */ #if 0 if (frame->tf_eip == (int)IDTVEC(syscall)) { /* * We've just entered system mode via the * syscall lcall. Continue single stepping * silently until the syscall handler has * saved the flags. */ goto out2; } if (frame->tf_eip == (int)IDTVEC(syscall) + 1) { /* * The syscall handler has now saved the * flags. Stop single stepping it. */ frame->tf_eflags &= ~PSL_T; goto out2; } #endif #if 0 /* * 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 */ load_dr6(rdr6() & 0xfffffff0); goto out2; } #endif /* * FALLTHROUGH (TRCTRAP kernel mode, kernel address) */ case T_BPTFLT: /* * If DDB is enabled, let it handle the debugger trap. * Otherwise, debugger traps "can't happen". */ #ifdef DDB MAKEMPSAFE(have_mplock); if (kdb_trap (type, 0, frame)) goto out2; #endif break; case T_DIVIDE: MAKEMPSAFE(have_mplock); trap_fatal(frame, FALSE, eva); goto out2; case T_NMI: MAKEMPSAFE(have_mplock); trap_fatal(frame, FALSE, eva); goto out2; case T_SYSCALL80: /* * Ignore this trap generated from a spurious SIGTRAP. * * single stepping in / syscalls leads to spurious / SIGTRAP * so ignore * * Haiku (c) 2007 Simon 'corecode' Schubert */ goto out2; } /* * Translate fault for emulators (e.g. Linux) */ if (*p->p_sysent->sv_transtrap) i = (*p->p_sysent->sv_transtrap)(i, type); MAKEMPSAFE(have_mplock); trapsignal(lp, i, ucode); #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 out2: ; if (have_mplock) rel_mplock(); #ifdef INVARIANTS KASSERT(crit_count == td->td_critcount, ("trap: critical section count mismatch! %d/%d", crit_count, td->td_pri)); KASSERT(curstop == td->td_toks_stop, ("trap: extra tokens held after trap! %zd/%zd", curstop - &td->td_toks_base, td->td_toks_stop - &td->td_toks_base)); #endif }
void trap(struct trapframe *frame) { struct globaldata *gd = mycpu; struct thread *td = gd->gd_curthread; struct lwp *lp = td->td_lwp; struct proc *p; int sticks = 0; int i = 0, ucode = 0, type, code; int have_mplock = 0; #ifdef INVARIANTS int crit_count = td->td_critcount; lwkt_tokref_t curstop = td->td_toks_stop; #endif vm_offset_t eva; p = td->td_proc; #ifdef DDB /* * We need to allow T_DNA faults when the debugger is active since * some dumping paths do large bcopy() which use the floating * point registers for faster copying. */ if (db_active && frame->tf_trapno != T_DNA) { eva = (frame->tf_trapno == T_PAGEFLT ? rcr2() : 0); ++gd->gd_trap_nesting_level; MAKEMPSAFE(have_mplock); trap_fatal(frame, eva); --gd->gd_trap_nesting_level; goto out2; } #endif eva = 0; ++gd->gd_trap_nesting_level; if (frame->tf_trapno == 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. * * XXX this should be in the switch statement, but the * NO_FOOF_HACK and VM86 goto and ifdefs obfuscate the * flow of control too much for this to be obviously * correct. */ eva = rcr2(); cpu_enable_intr(); } --gd->gd_trap_nesting_level; if (!(frame->tf_eflags & PSL_I)) { /* * 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. */ type = frame->tf_trapno; if (ISPL(frame->tf_cs)==SEL_UPL || (frame->tf_eflags & PSL_VM)) { MAKEMPSAFE(have_mplock); kprintf( "pid %ld (%s): trap %d with interrupts disabled\n", (long)curproc->p_pid, curproc->p_comm, type); } else if (type != T_BPTFLT && type != T_TRCTRAP) { /* * XXX not quite right, since this may be for a * multiple fault in user mode. */ MAKEMPSAFE(have_mplock); kprintf("kernel trap %d with interrupts disabled\n", type); } cpu_enable_intr(); } #if defined(I586_CPU) && !defined(NO_F00F_HACK) restart: #endif type = frame->tf_trapno; code = frame->tf_err; if (in_vm86call) { if (frame->tf_eflags & PSL_VM && (type == T_PROTFLT || type == T_STKFLT)) { KKASSERT(get_mplock_count(curthread) > 0); i = vm86_emulate((struct vm86frame *)frame); KKASSERT(get_mplock_count(curthread) > 0); if (i != 0) { /* * returns to original process */ vm86_trap((struct vm86frame *)frame, have_mplock); KKASSERT(0); /* NOT REACHED */ } goto out2; } switch (type) { /* * these traps want either a process context, or * assume a normal userspace trap. */ case T_PROTFLT: case T_SEGNPFLT: trap_fatal(frame, eva); goto out2; case T_TRCTRAP: type = T_BPTFLT; /* kernel breakpoint */ /* FALL THROUGH */ } goto kernel_trap; /* normal kernel trap handling */ } if ((ISPL(frame->tf_cs) == SEL_UPL) || (frame->tf_eflags & PSL_VM)) { /* user trap */ KTR_LOG(kernentry_trap, p->p_pid, lp->lwp_tid, frame->tf_trapno, eva); userenter(td, p); sticks = (int)td->td_sticks; lp->lwp_md.md_regs = frame; 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 */ frame->tf_eflags &= ~PSL_T; i = SIGTRAP; ucode = (type == T_TRCTRAP ? TRAP_TRACE : TRAP_BRKPT); break; case T_ARITHTRAP: /* arithmetic trap */ ucode = code; i = SIGFPE; break; case T_ASTFLT: /* Allow process switch */ mycpu->gd_cnt.v_soft++; if (mycpu->gd_reqflags & RQF_AST_OWEUPC) { atomic_clear_int(&mycpu->gd_reqflags, RQF_AST_OWEUPC); addupc_task(p, p->p_prof.pr_addr, p->p_prof.pr_ticks); } goto out; /* * 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 out; 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 */ case T_DOUBLEFLT: /* double fault */ default: i = SIGBUS; ucode = BUS_OBJERR; break; case T_PAGEFLT: /* page fault */ i = trap_pfault(frame, TRUE, eva); if (i == -1) goto out; #if defined(I586_CPU) && !defined(NO_F00F_HACK) if (i == -2) goto restart; #endif if (i == 0) goto out; if (i == SIGSEGV) ucode = SEGV_MAPERR; else { i = SIGSEGV; ucode = SEGV_ACCERR; } break; case T_DIVIDE: /* integer divide fault */ ucode = FPE_INTDIV; i = SIGFPE; break; #if NISA > 0 case T_NMI: MAKEMPSAFE(have_mplock); #ifdef POWERFAIL_NMI goto handle_powerfail; #else /* !POWERFAIL_NMI */ /* machine/parity/power fail/"kitchen sink" faults */ if (isa_nmi(code) == 0) { #ifdef DDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (ddb_on_nmi) { kprintf ("NMI ... going to debugger\n"); kdb_trap (type, 0, frame); } #endif /* DDB */ goto out2; } else if (panic_on_nmi) panic("NMI indicates hardware failure"); break; #endif /* POWERFAIL_NMI */ #endif /* NISA > 0 */ 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: /* * Virtual kernel intercept - pass the DNA exception * to the virtual kernel if it asked to handle it. * This occurs when the virtual kernel is holding * onto the FP context for a different emulated * process then the one currently running. * * We must still call npxdna() since we may have * saved FP state that the virtual kernel needs * to hand over to a different emulated process. */ if (lp->lwp_vkernel && lp->lwp_vkernel->ve && (td->td_pcb->pcb_flags & FP_VIRTFP) ) { npxdna(); break; } #if NNPX > 0 /* * The kernel may have switched out the FP unit's * state, causing the user process to take a fault * when it tries to use the FP unit. Restore the * state here */ if (npxdna()) goto out; #endif if (!pmath_emulate) { i = SIGFPE; ucode = FPE_FPU_NP_TRAP; break; } i = (*pmath_emulate)(frame); if (i == 0) { if (!(frame->tf_eflags & PSL_T)) goto out2; frame->tf_eflags &= ~PSL_T; i = SIGTRAP; } /* else ucode = emulator_only_knows() XXX */ 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: /* kernel trap */ switch (type) { case T_PAGEFLT: /* page fault */ trap_pfault(frame, FALSE, eva); goto out2; case T_DNA: #if NNPX > 0 /* * The kernel may be using npx for copying or other * purposes. */ if (npxdna()) goto out2; #endif break; case T_PROTFLT: /* general protection fault */ case T_SEGNPFLT: /* segment not present fault */ /* * 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. */ #define MAYBE_DORETI_FAULT(where, whereto) \ do { \ if (frame->tf_eip == (int)where) { \ frame->tf_eip = (int)whereto; \ goto out2; \ } \ } while (0) if (mycpu->gd_intr_nesting_level == 0) { /* * 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. */ MAYBE_DORETI_FAULT(doreti_iret, doreti_iret_fault); MAYBE_DORETI_FAULT(doreti_popl_ds, doreti_popl_ds_fault); MAYBE_DORETI_FAULT(doreti_popl_es, doreti_popl_es_fault); MAYBE_DORETI_FAULT(doreti_popl_fs, doreti_popl_fs_fault); MAYBE_DORETI_FAULT(doreti_popl_gs, doreti_popl_gs_fault); /* * NOTE: cpu doesn't push esp on kernel trap */ if (td->td_pcb->pcb_onfault && td->td_pcb->pcb_onfault_sp == (int)&frame->tf_esp) { frame->tf_eip = (register_t)td->td_pcb->pcb_onfault; goto out2; } } 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 out2; } break; case T_TRCTRAP: /* trace trap */ if (frame->tf_eip == (int)IDTVEC(syscall)) { /* * We've just entered system mode via the * syscall lcall. Continue single stepping * silently until the syscall handler has * saved the flags. */ goto out2; } if (frame->tf_eip == (int)IDTVEC(syscall) + 1) { /* * The syscall handler has now saved the * flags. Stop single stepping it. */ frame->tf_eflags &= ~PSL_T; goto out2; } /* * 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 */ load_dr6(rdr6() & 0xfffffff0); goto out2; } /* * FALLTHROUGH (TRCTRAP kernel mode, kernel address) */ case T_BPTFLT: /* * If DDB is enabled, let it handle the debugger trap. * Otherwise, debugger traps "can't happen". */ ucode = TRAP_BRKPT; #ifdef DDB MAKEMPSAFE(have_mplock); if (kdb_trap (type, 0, frame)) goto out2; #endif break; #if NISA > 0 case T_NMI: MAKEMPSAFE(have_mplock); #ifdef POWERFAIL_NMI #ifndef TIMER_FREQ # define TIMER_FREQ 1193182 #endif handle_powerfail: { static unsigned lastalert = 0; if (time_uptime - lastalert > 10) { log(LOG_WARNING, "NMI: power fail\n"); sysbeep(TIMER_FREQ/880, hz); lastalert = time_uptime; } /* YYY mp count */ goto out2; } #else /* !POWERFAIL_NMI */ /* machine/parity/power fail/"kitchen sink" faults */ if (isa_nmi(code) == 0) { #ifdef DDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (ddb_on_nmi) { kprintf ("NMI ... going to debugger\n"); kdb_trap (type, 0, frame); } #endif /* DDB */ goto out2; } else if (panic_on_nmi == 0) goto out2; /* FALL THROUGH */ #endif /* POWERFAIL_NMI */ #endif /* NISA > 0 */ } MAKEMPSAFE(have_mplock); trap_fatal(frame, eva); goto out2; } /* * Virtual kernel intercept - if the fault is directly related to a * VM context managed by a virtual kernel then let the virtual kernel * handle it. */ if (lp->lwp_vkernel && lp->lwp_vkernel->ve) { vkernel_trap(lp, frame); goto out; } /* Translate fault for emulators (e.g. Linux) */ if (*p->p_sysent->sv_transtrap) i = (*p->p_sysent->sv_transtrap)(i, type); MAKEMPSAFE(have_mplock); trapsignal(lp, i, ucode); #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 out: userret(lp, frame, sticks); userexit(lp); out2: ; if (have_mplock) rel_mplock(); if (p != NULL && lp != NULL) KTR_LOG(kernentry_trap_ret, p->p_pid, lp->lwp_tid); #ifdef INVARIANTS KASSERT(crit_count == td->td_critcount, ("trap: critical section count mismatch! %d/%d", crit_count, td->td_pri)); KASSERT(curstop == td->td_toks_stop, ("trap: extra tokens held after trap! %zd/%zd", curstop - &td->td_toks_base, td->td_toks_stop - &td->td_toks_base)); #endif }
void user_trap(struct trapframe *frame) { struct globaldata *gd = mycpu; struct thread *td = gd->gd_curthread; struct lwp *lp = td->td_lwp; struct proc *p; int sticks = 0; int i = 0, ucode = 0, type, code; int have_mplock = 0; #ifdef INVARIANTS int crit_count = td->td_critcount; lwkt_tokref_t curstop = td->td_toks_stop; #endif vm_offset_t eva; p = td->td_proc; /* * This is a bad kludge to avoid changing the various trapframe * structures. Because we are enabled as a virtual kernel, * the original tf_err field will be passed to us shifted 16 * over in the tf_trapno field for T_PAGEFLT. */ if (frame->tf_trapno == T_PAGEFLT) eva = frame->tf_err; else eva = 0; #if 0 kprintf("USER_TRAP AT %08x xflags %d trapno %d eva %08x\n", frame->tf_eip, frame->tf_xflags, frame->tf_trapno, eva); #endif /* * Everything coming from user mode runs through user_trap, * including system calls. */ if (frame->tf_trapno == T_SYSCALL80) { syscall2(frame); return; } KTR_LOG(kernentry_trap, lp->lwp_proc->p_pid, lp->lwp_tid, frame->tf_trapno, eva); #ifdef DDB if (db_active) { eva = (frame->tf_trapno == T_PAGEFLT ? rcr2() : 0); ++gd->gd_trap_nesting_level; MAKEMPSAFE(have_mplock); trap_fatal(frame, TRUE, eva); --gd->gd_trap_nesting_level; goto out2; } #endif #if defined(I586_CPU) && !defined(NO_F00F_HACK) restart: #endif type = frame->tf_trapno; code = frame->tf_err; userenter(td, p); sticks = (int)td->td_sticks; lp->lwp_md.md_regs = frame; 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 */ frame->tf_eflags &= ~PSL_T; i = SIGTRAP; ucode = (type == T_TRCTRAP ? TRAP_TRACE : TRAP_BRKPT); break; case T_ARITHTRAP: /* arithmetic trap */ ucode = code; i = SIGFPE; break; case T_ASTFLT: /* Allow process switch */ mycpu->gd_cnt.v_soft++; if (mycpu->gd_reqflags & RQF_AST_OWEUPC) { atomic_clear_int(&mycpu->gd_reqflags, RQF_AST_OWEUPC); addupc_task(p, p->p_prof.pr_addr, p->p_prof.pr_ticks); } goto out; /* * 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 0 if (frame->tf_eflags & PSL_VM) { i = vm86_emulate((struct vm86frame *)frame); if (i == 0) goto out; break; } #endif 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 */ case T_DOUBLEFLT: /* double fault */ default: i = SIGBUS; ucode = BUS_OBJERR; break; case T_PAGEFLT: /* page fault */ MAKEMPSAFE(have_mplock); i = trap_pfault(frame, TRUE, eva); if (i == -1) goto out; #if defined(I586_CPU) && !defined(NO_F00F_HACK) if (i == -2) goto restart; #endif if (i == 0) goto out; if (i == SIGSEGV) ucode = SEGV_MAPERR; else { i = SIGSEGV; ucode = SEGV_ACCERR; } break; case T_DIVIDE: /* integer divide fault */ ucode = FPE_INTDIV; i = SIGFPE; break; #if NISA > 0 case T_NMI: MAKEMPSAFE(have_mplock); /* machine/parity/power fail/"kitchen sink" faults */ if (isa_nmi(code) == 0) { #ifdef DDB /* * NMI can be hooked up to a pushbutton * for debugging. */ if (ddb_on_nmi) { kprintf ("NMI ... going to debugger\n"); kdb_trap (type, 0, frame); } #endif /* DDB */ goto out2; } else if (panic_on_nmi) panic("NMI indicates hardware failure"); break; #endif /* NISA > 0 */ 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: /* * Virtual kernel intercept - pass the DNA exception * to the (emulated) virtual kernel if it asked to handle * it. This occurs when the virtual kernel is holding * onto the FP context for a different emulated * process then the one currently running. * * We must still call npxdna() since we may have * saved FP state that the (emulated) virtual kernel * needs to hand over to a different emulated process. */ if (lp->lwp_vkernel && lp->lwp_vkernel->ve && (td->td_pcb->pcb_flags & FP_VIRTFP) ) { npxdna(frame); break; } #if NNPX > 0 /* * The kernel may have switched out the FP unit's * state, causing the user process to take a fault * when it tries to use the FP unit. Restore the * state here */ if (npxdna(frame)) goto out; #endif if (!pmath_emulate) { i = SIGFPE; ucode = FPE_FPU_NP_TRAP; break; } i = (*pmath_emulate)(frame); if (i == 0) { if (!(frame->tf_eflags & PSL_T)) goto out2; frame->tf_eflags &= ~PSL_T; i = SIGTRAP; } /* else ucode = emulator_only_knows() XXX */ 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; } /* * Virtual kernel intercept - if the fault is directly related to a * VM context managed by a virtual kernel then let the virtual kernel * handle it. */ if (lp->lwp_vkernel && lp->lwp_vkernel->ve) { vkernel_trap(lp, frame); goto out; } /* * Translate fault for emulators (e.g. Linux) */ if (*p->p_sysent->sv_transtrap) i = (*p->p_sysent->sv_transtrap)(i, type); MAKEMPSAFE(have_mplock); trapsignal(lp, i, ucode); #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 out: userret(lp, frame, sticks); userexit(lp); out2: ; if (have_mplock) rel_mplock(); KTR_LOG(kernentry_trap_ret, lp->lwp_proc->p_pid, lp->lwp_tid); #ifdef INVARIANTS KASSERT(crit_count == td->td_critcount, ("trap: critical section count mismatch! %d/%d", crit_count, td->td_pri)); KASSERT(curstop == td->td_toks_stop, ("trap: extra tokens held after trap! %zd/%zd", curstop - &td->td_toks_base, td->td_toks_stop - &td->td_toks_base)); #endif }