void trap(struct trapframe *frame) { struct thread *td; struct proc *p; int sig, type, user; ksiginfo_t ksi; #ifdef KDB if (kdb_active) { kdb_reenter(); return; } #endif PCPU_INC(cnt.v_trap); td = curthread; p = td->td_proc; type = frame->exc; sig = 0; user = (frame->srr1 & PSL_PR) ? 1 : 0; CTR3(KTR_TRAP, "trap: %s type=%s (%s)", p->p_comm, trapname(type), user ? "user" : "kernel"); if (user) { td->td_frame = frame; if (td->td_ucred != p->p_ucred) cred_update_thread(td); /* User Mode Traps */ switch (type) { case EXC_DSI: case EXC_ISI: sig = trap_pfault(frame, 1); break; case EXC_SC: syscall(frame); break; case EXC_ALI: if (fix_unaligned(td, frame) != 0) sig = SIGBUS; else frame->srr0 += 4; break; case EXC_DEBUG: /* Single stepping */ mtspr(SPR_DBSR, mfspr(SPR_DBSR)); frame->srr1 &= ~PSL_DE; frame->cpu.booke.dbcr0 &= ~(DBCR0_IDM || DBCR0_IC); sig = SIGTRAP; break; case EXC_PGM: /* Program exception */ #ifdef FPU_EMU sig = fpu_emulate(frame, (struct fpreg *)&td->td_pcb->pcb_fpu); #else /* XXX SIGILL for non-trap instructions. */ sig = SIGTRAP; #endif break; default: trap_fatal(frame); } } else { /* Kernel Mode Traps */ KASSERT(cold || td->td_ucred != NULL, ("kernel trap doesn't have ucred")); switch (type) { case EXC_DEBUG: mtspr(SPR_DBSR, mfspr(SPR_DBSR)); kdb_trap(frame->exc, 0, frame); return; case EXC_DSI: if (trap_pfault(frame, 0) == 0) return; break; case EXC_MCHK: if (handle_onfault(frame)) return; break; #ifdef KDB case EXC_PGM: if (frame->cpu.booke.esr & ESR_PTR) kdb_trap(EXC_PGM, 0, frame); return; #endif default: break; } trap_fatal(frame); } if (sig != 0) { if (p->p_sysent->sv_transtrap != NULL) sig = (p->p_sysent->sv_transtrap)(sig, type); ksiginfo_init_trap(&ksi); ksi.ksi_signo = sig; ksi.ksi_code = type; /* XXX, not POSIX */ /* ksi.ksi_addr = ? */ ksi.ksi_trapno = type; trapsignal(td, &ksi); } userret(td, frame); }
static int trap_pfault(struct trapframe *frame, int user) { vm_offset_t eva, va; struct thread *td; struct proc *p; vm_map_t map; vm_prot_t ftype; int rv; td = curthread; p = td->td_proc; if (frame->exc == EXC_ISI) { eva = frame->srr0; ftype = VM_PROT_READ | VM_PROT_EXECUTE; } else { eva = frame->cpu.booke.dear; if (frame->cpu.booke.esr & ESR_ST) ftype = VM_PROT_WRITE; else ftype = VM_PROT_READ; } if (user) { KASSERT(p->p_vmspace != NULL, ("trap_pfault: vmspace NULL")); map = &p->p_vmspace->vm_map; } else { if (eva < VM_MAXUSER_ADDRESS) { if (p->p_vmspace == NULL) return (SIGSEGV); map = &p->p_vmspace->vm_map; } else { map = kernel_map; } } va = trunc_page(eva); 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, 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); if (!user && handle_onfault(frame)) return (0); return ((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV); }
void trap(struct trapframe *frame) { struct thread *td; struct proc *p; #ifdef KDTRACE_HOOKS uint32_t inst; #endif int sig, type, user; u_int ucode; ksiginfo_t ksi; PCPU_INC(cnt.v_trap); td = curthread; p = td->td_proc; type = ucode = frame->exc; sig = 0; user = frame->srr1 & PSL_PR; CTR3(KTR_TRAP, "trap: %s type=%s (%s)", td->td_name, trapname(type), user ? "user" : "kernel"); #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 its 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 (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, type) != 0) return; #endif if (user) { td->td_pticks = 0; td->td_frame = frame; if (td->td_cowgen != p->p_cowgen) thread_cow_update(td); /* User Mode Traps */ switch (type) { case EXC_RUNMODETRC: case EXC_TRC: frame->srr1 &= ~PSL_SE; sig = SIGTRAP; ucode = TRAP_TRACE; break; #ifdef __powerpc64__ case EXC_ISE: case EXC_DSE: if (handle_user_slb_spill(&p->p_vmspace->vm_pmap, (type == EXC_ISE) ? frame->srr0 : frame->dar) != 0){ sig = SIGSEGV; ucode = SEGV_MAPERR; } break; #endif case EXC_DSI: case EXC_ISI: sig = trap_pfault(frame, 1); if (sig == SIGSEGV) ucode = SEGV_MAPERR; break; case EXC_SC: syscall(frame); break; case EXC_FPU: KASSERT((td->td_pcb->pcb_flags & PCB_FPU) != PCB_FPU, ("FPU already enabled for thread")); enable_fpu(td); break; case EXC_VEC: KASSERT((td->td_pcb->pcb_flags & PCB_VEC) != PCB_VEC, ("Altivec already enabled for thread")); enable_vec(td); break; case EXC_VSX: KASSERT((td->td_pcb->pcb_flags & PCB_VSX) != PCB_VSX, ("VSX already enabled for thread")); if (!(td->td_pcb->pcb_flags & PCB_VEC)) enable_vec(td); if (!(td->td_pcb->pcb_flags & PCB_FPU)) save_fpu(td); td->td_pcb->pcb_flags |= PCB_VSX; enable_fpu(td); break; case EXC_VECAST_G4: case EXC_VECAST_G5: /* * We get a VPU assist exception for IEEE mode * vector operations on denormalized floats. * Emulating this is a giant pain, so for now, * just switch off IEEE mode and treat them as * zero. */ save_vec(td); td->td_pcb->pcb_vec.vscr |= ALTIVEC_VSCR_NJ; enable_vec(td); break; case EXC_ALI: if (fix_unaligned(td, frame) != 0) { sig = SIGBUS; ucode = BUS_ADRALN; } else frame->srr0 += 4; break; case EXC_DEBUG: /* Single stepping */ mtspr(SPR_DBSR, mfspr(SPR_DBSR)); frame->srr1 &= ~PSL_DE; frame->cpu.booke.dbcr0 &= ~(DBCR0_IDM || DBCR0_IC); sig = SIGTRAP; ucode = TRAP_TRACE; break; case EXC_PGM: /* Identify the trap reason */ #ifdef AIM if (frame->srr1 & EXC_PGM_TRAP) { #else if (frame->cpu.booke.esr & ESR_PTR) { #endif #ifdef KDTRACE_HOOKS inst = fuword32((const void *)frame->srr0); if (inst == 0x0FFFDDDD && dtrace_pid_probe_ptr != NULL) { struct reg regs; fill_regs(td, ®s); (*dtrace_pid_probe_ptr)(®s); break; } #endif sig = SIGTRAP; ucode = TRAP_BRKPT; } else { sig = ppc_instr_emulate(frame, td->td_pcb); if (sig == SIGILL) { if (frame->srr1 & EXC_PGM_PRIV) ucode = ILL_PRVOPC; else if (frame->srr1 & EXC_PGM_ILLEGAL) ucode = ILL_ILLOPC; } else if (sig == SIGFPE) ucode = FPE_FLTINV; /* Punt for now, invalid operation. */ } break; case EXC_MCHK: /* * Note that this may not be recoverable for the user * process, depending on the type of machine check, * but it at least prevents the kernel from dying. */ sig = SIGBUS; ucode = BUS_OBJERR; break; default: trap_fatal(frame); } } else { /* Kernel Mode Traps */ KASSERT(cold || td->td_ucred != NULL, ("kernel trap doesn't have ucred")); switch (type) { #ifdef KDTRACE_HOOKS case EXC_PGM: if (frame->srr1 & EXC_PGM_TRAP) { if (*(uint32_t *)frame->srr0 == EXC_DTRACE) { if (dtrace_invop_jump_addr != NULL) { dtrace_invop_jump_addr(frame); return; } } } break; #endif #ifdef __powerpc64__ case EXC_DSE: if ((frame->dar & SEGMENT_MASK) == USER_ADDR) { __asm __volatile ("slbmte %0, %1" :: "r"(td->td_pcb->pcb_cpu.aim.usr_vsid), "r"(USER_SLB_SLBE)); return; } break; #endif case EXC_DSI: if (trap_pfault(frame, 0) == 0) return; break; case EXC_MCHK: if (handle_onfault(frame)) return; break; default: break; } trap_fatal(frame); }