/* * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) * Copyright 2007-2010 Freescale Semiconductor, Inc. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Modified by Cort Dougan (cort@cs.nmt.edu) * and Paul Mackerras (paulus@samba.org) */ /* * This file handles the architecture-dependent parts of hardware exceptions */ #include #include #include #include #include #include #include #include #include #include #include #include #include /* print_modules */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_PMAC_BACKLIGHT #include #endif #ifdef CONFIG_PPC64 #include #include #include #endif #include #include #include #include #include #include #include #include #include #include #include #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC_CORE) int (*__debugger)(struct pt_regs *regs) __read_mostly; int (*__debugger_ipi)(struct pt_regs *regs) __read_mostly; int (*__debugger_bpt)(struct pt_regs *regs) __read_mostly; int (*__debugger_sstep)(struct pt_regs *regs) __read_mostly; int (*__debugger_iabr_match)(struct pt_regs *regs) __read_mostly; int (*__debugger_break_match)(struct pt_regs *regs) __read_mostly; int (*__debugger_fault_handler)(struct pt_regs *regs) __read_mostly; EXPORT_SYMBOL(__debugger); EXPORT_SYMBOL(__debugger_ipi); EXPORT_SYMBOL(__debugger_bpt); EXPORT_SYMBOL(__debugger_sstep); EXPORT_SYMBOL(__debugger_iabr_match); EXPORT_SYMBOL(__debugger_break_match); EXPORT_SYMBOL(__debugger_fault_handler); #endif /* Transactional Memory trap debug */ #ifdef TM_DEBUG_SW #define TM_DEBUG(x...) printk(KERN_INFO x) #else #define TM_DEBUG(x...) do { } while(0) #endif /* * Trap & Exception support */ #ifdef CONFIG_PMAC_BACKLIGHT static void pmac_backlight_unblank(void) { mutex_lock(&pmac_backlight_mutex); if (pmac_backlight) { struct backlight_properties *props; props = &pmac_backlight->props; props->brightness = props->max_brightness; props->power = FB_BLANK_UNBLANK; backlight_update_status(pmac_backlight); } mutex_unlock(&pmac_backlight_mutex); } #else static inline void pmac_backlight_unblank(void) { } #endif static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED; static int die_owner = -1; static unsigned int die_nest_count; static int die_counter; static unsigned long oops_begin(struct pt_regs *regs) { int cpu; unsigned long flags; oops_enter(); /* racy, but better than risking deadlock. */ raw_local_irq_save(flags); cpu = smp_processor_id(); if (!arch_spin_trylock(&die_lock)) { if (cpu == die_owner) /* nested oops. should stop eventually */; else arch_spin_lock(&die_lock); } die_nest_count++; die_owner = cpu; console_verbose(); bust_spinlocks(1); if (machine_is(powermac)) pmac_backlight_unblank(); return flags; } NOKPROBE_SYMBOL(oops_begin); static void oops_end(unsigned long flags, struct pt_regs *regs, int signr) { bust_spinlocks(0); add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); die_nest_count--; oops_exit(); printk("\n"); if (!die_nest_count) { /* Nest count reaches zero, release the lock. */ die_owner = -1; arch_spin_unlock(&die_lock); } raw_local_irq_restore(flags); crash_fadump(regs, "die oops"); /* * A system reset (0x100) is a request to dump, so we always send * it through the crashdump code. */ if (kexec_should_crash(current) || (TRAP(regs) == 0x100)) { crash_kexec(regs); /* * We aren't the primary crash CPU. We need to send it * to a holding pattern to avoid it ending up in the panic * code. */ crash_kexec_secondary(regs); } if (!signr) return; /* * While our oops output is serialised by a spinlock, output * from panic() called below can race and corrupt it. If we * know we are going to panic, delay for 1 second so we have a * chance to get clean backtraces from all CPUs that are oopsing. */ if (in_interrupt() || panic_on_oops || !current->pid || is_global_init(current)) { mdelay(MSEC_PER_SEC); } if (in_interrupt()) panic("Fatal exception in interrupt"); if (panic_on_oops) panic("Fatal exception"); do_exit(signr); } NOKPROBE_SYMBOL(oops_end); static int __die(const char *str, struct pt_regs *regs, long err) { printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter); #ifdef CONFIG_PREEMPT printk("PREEMPT "); #endif #ifdef CONFIG_SMP printk("SMP NR_CPUS=%d ", NR_CPUS); #endif if (debug_pagealloc_enabled()) printk("DEBUG_PAGEALLOC "); #ifdef CONFIG_NUMA printk("NUMA "); #endif printk("%s\n", ppc_md.name ? ppc_md.name : ""); if (notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV) == NOTIFY_STOP) return 1; print_modules(); show_regs(regs); return 0; } NOKPROBE_SYMBOL(__die); void die(const char *str, struct pt_regs *regs, long err) { unsigned long flags; if (debugger(regs)) return; flags = oops_begin(regs); if (__die(str, regs, err)) err = 0; oops_end(flags, regs, err); } void user_single_step_siginfo(struct task_struct *tsk, struct pt_regs *regs, siginfo_t *info) { memset(info, 0, sizeof(*info)); info->si_signo = SIGTRAP; info->si_code = TRAP_TRACE; info->si_addr = (void __user *)regs->nip; } void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) { siginfo_t info; const char fmt32[] = KERN_INFO "%s[%d]: unhandled signal %d " \ "at %08lx nip %08lx lr %08lx code %x\n"; const char fmt64[] = KERN_INFO "%s[%d]: unhandled signal %d " \ "at %016lx nip %016lx lr %016lx code %x\n"; if (!user_mode(regs)) { die("Exception in kernel mode", regs, signr); return; } if (show_unhandled_signals && unhandled_signal(current, signr)) { printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32, current->comm, current->pid, signr, addr, regs->nip, regs->link, code); } if (arch_irqs_disabled() && !arch_irq_disabled_regs(regs)) local_irq_enable(); current->thread.trap_nr = code; memset(&info, 0, sizeof(info)); info.si_signo = signr; info.si_code = code; info.si_addr = (void __user *) addr; force_sig_info(signr, &info, current); } void system_reset_exception(struct pt_regs *regs) { /* See if any machine dependent calls */ if (ppc_md.system_reset_exception) { if (ppc_md.system_reset_exception(regs)) return; } die("System Reset", regs, SIGABRT); /* Must die if the interrupt is not recoverable */ if (!(regs->msr & MSR_RI)) panic("Unrecoverable System Reset"); /* What should we do here? We could issue a shutdown or hard reset. */ } #ifdef CONFIG_PPC64 /* * This function is called in real mode. Strictly no printk's please. * * regs->nip and regs->msr contains srr0 and ssr1. */ long machine_check_early(struct pt_regs *regs) { long handled = 0; __this_cpu_inc(irq_stat.mce_exceptions); add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); if (cur_cpu_spec && cur_cpu_spec->machine_check_early) handled = cur_cpu_spec->machine_check_early(regs); return handled; } long hmi_exception_realmode(struct pt_regs *regs) { __this_cpu_inc(irq_stat.hmi_exceptions); wait_for_subcore_guest_exit(); if (ppc_md.hmi_exception_early) ppc_md.hmi_exception_early(regs); wait_for_tb_resync(); return 0; } #endif /* * I/O accesses can cause machine checks on powermacs. * Check if the NIP corresponds to the address of a sync * instruction for which there is an entry in the exception * table. * Note that the 601 only takes a machine check on TEA * (transfer error ack) signal assertion, and does not * set any of the top 16 bits of SRR1. * -- paulus. */ static inline int check_io_access(struct pt_regs *regs) { #ifdef CONFIG_PPC32 unsigned long msr = regs->msr; const struct exception_table_entry *entry; unsigned int *nip = (unsigned int *)regs->nip; if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000))) && (entry = search_exception_tables(regs->nip)) != NULL) { /* * Check that it's a sync instruction, or somewhere * in the twi; isync; nop sequence that inb/inw/inl uses. * As the address is in the exception table * we should be able to read the instr there. * For the debug message, we look at the preceding * load or store. */ if (*nip == PPC_INST_NOP) nip -= 2; else if (*nip == PPC_INST_ISYNC) --nip; if (*nip == PPC_INST_SYNC || (*nip >> 26) == OP_TRAP) { unsigned int rb; --nip; rb = (*nip >> 11) & 0x1f; printk(KERN_DEBUG "%s bad port %lx at %p\n", (*nip & 0x100)? "OUT to": "IN from", regs->gpr[rb] - _IO_BASE, nip); regs->msr |= MSR_RI; regs->nip = extable_fixup(entry); return 1; } } #endif /* CONFIG_PPC32 */ return 0; } #ifdef CONFIG_PPC_ADV_DEBUG_REGS /* On 4xx, the reason for the machine check or program exception is in the ESR. */ #define get_reason(regs) ((regs)->dsisr) #ifndef CONFIG_FSL_BOOKE #define get_mc_reason(regs) ((regs)->dsisr) #else #define get_mc_reason(regs) (mfspr(SPRN_MCSR)) #endif #define REASON_FP ESR_FP #define REASON_ILLEGAL (ESR_PIL | ESR_PUO) #define REASON_PRIVILEGED ESR_PPR #define REASON_TRAP ESR_PTR /* single-step stuff */ #define single_stepping(regs) (current->thread.debug.dbcr0 & DBCR0_IC) #define clear_single_step(regs) (current->thread.debug.dbcr0 &= ~DBCR0_IC) #else /* On non-4xx, the reason for the machine check or program exception is in the MSR. */ #define get_reason(regs) ((regs)->msr) #define get_mc_reason(regs) ((regs)->msr) #define REASON_TM 0x200000 #define REASON_FP 0x100000 #define REASON_ILLEGAL 0x80000 #define REASON_PRIVILEGED 0x40000 #define REASON_TRAP 0x20000 #define single_stepping(regs) ((regs)->msr & MSR_SE) #define clear_single_step(regs) ((regs)->msr &= ~MSR_SE) #endif #if defined(CONFIG_4xx) int machine_check_4xx(struct pt_regs *regs) { unsigned long reason = get_mc_reason(regs); if (reason & ESR_IMCP) { printk("Instruction"); mtspr(SPRN_ESR, reason & ~ESR_IMCP); } else printk("Data"); printk(" machine check in kernel mode.\n"); return 0; } int machine_check_440A(struct pt_regs *regs) { unsigned long reason = get_mc_reason(regs); printk("Machine check in kernel mode.\n"); if (reason & ESR_IMCP){ printk("Instruction Synchronous Machine Check exception\n"); mtspr(SPRN_ESR, reason & ~ESR_IMCP); } else { u32 mcsr = mfspr(SPRN_MCSR); if (mcsr & MCSR_IB) printk("Instruction Read PLB Error\n"); if (mcsr & MCSR_DRB) printk("Data Read PLB Error\n"); if (mcsr & MCSR_DWB) printk("Data Write PLB Error\n"); if (mcsr & MCSR_TLBP) printk("TLB Parity Error\n"); if (mcsr & MCSR_ICP){ flush_instruction_cache(); printk("I-Cache Parity Error\n"); } if (mcsr & MCSR_DCSP) printk("D-Cache Search Parity Error\n"); if (mcsr & MCSR_DCFP) printk("D-Cache Flush Parity Error\n"); if (mcsr & MCSR_IMPE) printk("Machine Check exception is imprecise\n"); /* Clear MCSR */ mtspr(SPRN_MCSR, mcsr); } return 0; } int machine_check_47x(struct pt_regs *regs) { unsigned long reason = get_mc_reason(regs); u32 mcsr; printk(KERN_ERR "Machine check in kernel mode.\n"); if (reason & ESR_IMCP) { printk(KERN_ERR "Instruction Synchronous Machine Check exception\n"); mtspr(SPRN_ESR, reason & ~ESR_IMCP); return 0; } mcsr = mfspr(SPRN_MCSR); if (mcsr & MCSR_IB) printk(KERN_ERR "Instruction Read PLB Error\n"); if (mcsr & MCSR_DRB) printk(KERN_ERR "Data Read PLB Error\n"); if (mcsr & MCSR_DWB) printk(KERN_ERR "Data Write PLB Error\n"); if (mcsr & MCSR_TLBP) printk(KERN_ERR "TLB Parity Error\n"); if (mcsr & MCSR_ICP) { flush_instruction_cache(); printk(KERN_ERR "I-Cache Parity Error\n"); } if (mcsr & MCSR_DCSP) printk(KERN_ERR "D-Cache Search Parity Error\n"); if (mcsr & PPC47x_MCSR_GPR) printk(KERN_ERR "GPR Parity Error\n"); if (mcsr & PPC47x_MCSR_FPR) printk(KERN_ERR "FPR Parity Error\n"); if (mcsr & PPC47x_MCSR_IPR) printk(KERN_ERR "Machine Check exception is imprecise\n"); /* Clear MCSR */ mtspr(SPRN_MCSR, mcsr); return 0; } #elif defined(CONFIG_E500) int machine_check_e500mc(struct pt_regs *regs) { unsigned long mcsr = mfspr(SPRN_MCSR); unsigned long reason = mcsr; int recoverable = 1; if (reason & MCSR_LD) { recoverable = fsl_rio_mcheck_exception(regs); if (recoverable == 1) goto silent_out; } printk("Machine check in kernel mode.\n"); printk("Caused by (from MCSR=%lx): ", reason); if (reason & MCSR_MCP) printk("Machine Check Signal\n"); if (reason & MCSR_ICPERR) { printk("Instruction Cache Parity Error\n"); /* * This is recoverable by invalidating the i-cache. */ mtspr(SPRN_L1CSR1, mfspr(SPRN_L1CSR1) | L1CSR1_ICFI); while (mfspr(SPRN_L1CSR1) & L1CSR1_ICFI) ; /* * This will generally be accompanied by an instruction * fetch error report -- only treat MCSR_IF as fatal * if it wasn't due to an L1 parity error. */ reason &= ~MCSR_IF; } if (reason & MCSR_DCPERR_MC) { printk("Data Cache Parity Error\n"); /* * In write shadow mode we auto-recover from the error, but it * may still get logged and cause a machine check. We should * only treat the non-write shadow case as non-recoverable. */ if (!(mfspr(SPRN_L1CSR2) & L1CSR2_DCWS)) recoverable = 0; } if (reason & MCSR_L2MMU_MHIT) { printk("Hit on multiple TLB entries\n"); recoverable = 0; } if (reason & MCSR_NMI) printk("Non-maskable interrupt\n"); if (reason & MCSR_IF) { printk("Instruction Fetch Error Report\n"); recoverable = 0; } if (reason & MCSR_LD) { printk("Load Error Report\n"); recoverable = 0; } if (reason & MCSR_ST) { printk("Store Error Report\n"); recoverable = 0; } if (reason & MCSR_LDG) { printk("Guarded Load Error Report\n"); recoverable = 0; } if (reason & MCSR_TLBSYNC) printk("Simultaneous tlbsync operations\n"); if (reason & MCSR_BSL2_ERR) { printk("Level 2 Cache Error\n"); recoverable = 0; } if (reason & MCSR_MAV) { u64 addr; addr = mfspr(SPRN_MCAR); addr |= (u64)mfspr(SPRN_MCARU) << 32; printk("Machine Check %s Address: %#llx\n", reason & MCSR_MEA ? "Effective" : "Physical", addr); } silent_out: mtspr(SPRN_MCSR, mcsr); return mfspr(SPRN_MCSR) == 0 && recoverable; } int machine_check_e500(struct pt_regs *regs) { unsigned long reason = get_mc_reason(regs); if (reason & MCSR_BUS_RBERR) { if (fsl_rio_mcheck_exception(regs)) return 1; if (fsl_pci_mcheck_exception(regs)) return 1; } printk("Machine check in kernel mode.\n"); printk("Caused by (from MCSR=%lx): ", reason); if (reason & MCSR_MCP) printk("Machine Check Signal\n"); if (reason & MCSR_ICPERR) printk("Instruction Cache Parity Error\n"); if (reason & MCSR_DCP_PERR) printk("Data Cache Push Parity Error\n"); if (reason & MCSR_DCPERR) printk("Data Cache Parity Error\n"); if (reason & MCSR_BUS_IAERR) printk("Bus - Instruction Address Error\n"); if (reason & MCSR_BUS_RAERR) printk("Bus - Read Address Error\n"); if (reason & MCSR_BUS_WAERR) printk("Bus - Write Address Error\n"); if (reason & MCSR_BUS_IBERR) printk("Bus - Instruction Data Error\n"); if (reason & MCSR_BUS_RBERR) printk("Bus - Read Data Bus Error\n"); if (reason & MCSR_BUS_WBERR) printk("Bus - Write Data Bus Error\n"); if (reason & MCSR_BUS_IPERR) printk("Bus - Instruction Parity Error\n"); if (reason & MCSR_BUS_RPERR) printk("Bus - Read Parity Error\n"); return 0; } int machine_check_generic(struct pt_regs *regs) { return 0; } #elif defined(CONFIG_E200) int machine_check_e200(struct pt_regs *regs) { unsigned long reason = get_mc_reason(regs); printk("Machine check in kernel mode.\n"); printk("Caused by (from MCSR=%lx): ", reason); if (reason & MCSR_MCP) printk("Machine Check Signal\n"); if (reason & MCSR_CP_PERR) printk("Cache Push Parity Error\n"); if (reason & MCSR_CPERR) printk("Cache Parity Error\n"); if (reason & MCSR_EXCP_ERR) printk("ISI, ITLB, or Bus Error on first instruction fetch for an exception handler\n"); if (reason & MCSR_BUS_IRERR) printk("Bus - Read Bus Error on instruction fetch\n"); if (reason & MCSR_BUS_DRERR) printk("Bus - Read Bus Error on data load\n"); if (reason & MCSR_BUS_WRERR) printk("Bus - Write Bus Error on buffered store or cache line push\n"); return 0; } #elif defined(CONFIG_PPC_8xx) int machine_check_8xx(struct pt_regs *regs) { unsigned long reason = get_mc_reason(regs); pr_err("Machine check in kernel mode.\n"); pr_err("Caused by (from SRR1=%lx): ", reason); if (reason & 0x40000000) pr_err("Fetch error at address %lx\n", regs->nip); else pr_err("Data access error at address %lx\n", regs->dar); #ifdef CONFIG_PCI /* the qspan pci read routines can cause machine checks -- Cort * * yuck !!! that totally needs to go away ! There are better ways * to deal with that than having a wart in the mcheck handler. * -- BenH */ bad_page_fault(regs, regs->dar, SIGBUS); return 1; #else return 0; #endif } #else int machine_check_generic(struct pt_regs *regs) { unsigned long reason = get_mc_reason(regs); printk("Machine check in kernel mode.\n"); printk("Caused by (from SRR1=%lx): ", reason); switch (reason & 0x601F0000) { case 0x80000: printk("Machine check signal\n"); break; case 0: /* for 601 */ case 0x40000: case 0x140000: /* 7450 MSS error and TEA */ printk("Transfer error ack signal\n"); break; case 0x20000: printk("Data parity error signal\n"); break; case 0x10000: printk("Address parity error signal\n"); break; case 0x20000000: printk("L1 Data Cache error\n"); break; case 0x40000000: printk("L1 Instruction Cache error\n"); break; case 0x00100000: printk("L2 data cache parity error\n"); break; default: printk("Unknown values in msr\n"); } return 0; } #endif /* everything else */ void machine_check_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); int recover = 0; __this_cpu_inc(irq_stat.mce_exceptions); /* See if any machine dependent calls. In theory, we would want * to call the CPU first, and call the ppc_md. one if the CPU * one returns a positive number. However there is existing code * that assumes the board gets a first chance, so let's keep it * that way for now and fix things later. --BenH. */ if (ppc_md.machine_check_exception) recover = ppc_md.machine_check_exception(regs); else if (cur_cpu_spec->machine_check) recover = cur_cpu_spec->machine_check(regs); if (recover > 0) goto bail; if (debugger_fault_handler(regs)) goto bail; if (check_io_access(regs)) goto bail; die("Machine check", regs, SIGBUS); /* Must die if the interrupt is not recoverable */ if (!(regs->msr & MSR_RI)) panic("Unrecoverable Machine check"); bail: exception_exit(prev_state); } void SMIException(struct pt_regs *regs) { die("System Management Interrupt", regs, SIGABRT); } void handle_hmi_exception(struct pt_regs *regs) { struct pt_regs *old_regs; old_regs = set_irq_regs(regs); irq_enter(); if (ppc_md.handle_hmi_exception) ppc_md.handle_hmi_exception(regs); irq_exit(); set_irq_regs(old_regs); } void unknown_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", regs->nip, regs->msr, regs->trap); _exception(SIGTRAP, regs, 0, 0); exception_exit(prev_state); } void instruction_breakpoint_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5, 5, SIGTRAP) == NOTIFY_STOP) goto bail; if (debugger_iabr_match(regs)) goto bail; _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip); bail: exception_exit(prev_state); } void RunModeException(struct pt_regs *regs) { _exception(SIGTRAP, regs, 0, 0); } void single_step_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); clear_single_step(regs); if (kprobe_post_handler(regs)) return; if (notify_die(DIE_SSTEP, "single_step", regs, 5, 5, SIGTRAP) == NOTIFY_STOP) goto bail; if (debugger_sstep(regs)) goto bail; _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip); bail: exception_exit(prev_state); } NOKPROBE_SYMBOL(single_step_exception); /* * After we have successfully emulated an instruction, we have to * check if the instruction was being single-stepped, and if so, * pretend we got a single-step exception. This was pointed out * by Kumar Gala. -- paulus */ static void emulate_single_step(struct pt_regs *regs) { if (single_stepping(regs)) single_step_exception(regs); } static inline int __parse_fpscr(unsigned long fpscr) { int ret = 0; /* Invalid operation */ if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX)) ret = FPE_FLTINV; /* Overflow */ else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX)) ret = FPE_FLTOVF; /* Underflow */ else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX)) ret = FPE_FLTUND; /* Divide by zero */ else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX)) ret = FPE_FLTDIV; /* Inexact result */ else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX)) ret = FPE_FLTRES; return ret; } static void parse_fpe(struct pt_regs *regs) { int code = 0; flush_fp_to_thread(current); code = __parse_fpscr(current->thread.fp_state.fpscr); _exception(SIGFPE, regs, code, regs->nip); } /* * Illegal instruction emulation support. Originally written to * provide the PVR to user applications using the mfspr rd, PVR. * Return non-zero if we can't emulate, or -EFAULT if the associated * memory access caused an access fault. Return zero on success. * * There are a couple of ways to do this, either "decode" the instruction * or directly match lots of bits. In this case, matching lots of * bits is faster and easier. * */ static int emulate_string_inst(struct pt_regs *regs, u32 instword) { u8 rT = (instword >> 21) & 0x1f; u8 rA = (instword >> 16) & 0x1f; u8 NB_RB = (instword >> 11) & 0x1f; u32 num_bytes; unsigned long EA; int pos = 0; /* Early out if we are an invalid form of lswx */ if ((instword & PPC_INST_STRING_MASK) == PPC_INST_LSWX) if ((rT == rA) || (rT == NB_RB)) return -EINVAL; EA = (rA == 0) ? 0 : regs->gpr[rA]; switch (instword & PPC_INST_STRING_MASK) { case PPC_INST_LSWX: case PPC_INST_STSWX: EA += NB_RB; num_bytes = regs->xer & 0x7f; break; case PPC_INST_LSWI: case PPC_INST_STSWI: num_bytes = (NB_RB == 0) ? 32 : NB_RB; break; default: return -EINVAL; } while (num_bytes != 0) { u8 val; u32 shift = 8 * (3 - (pos & 0x3)); /* if process is 32-bit, clear upper 32 bits of EA */ if ((regs->msr & MSR_64BIT) == 0) EA &= 0xFFFFFFFF; switch ((instword & PPC_INST_STRING_MASK)) { case PPC_INST_LSWX: case PPC_INST_LSWI: if (get_user(val, (u8 __user *)EA)) return -EFAULT; /* first time updating this reg, * zero it out */ if (pos == 0) regs->gpr[rT] = 0; regs->gpr[rT] |= val << shift; break; case PPC_INST_STSWI: case PPC_INST_STSWX: val = regs->gpr[rT] >> shift; if (put_user(val, (u8 __user *)EA)) return -EFAULT; break; } /* move EA to next address */ EA += 1; num_bytes--; /* manage our position within the register */ if (++pos == 4) { pos = 0; if (++rT == 32) rT = 0; } } return 0; } static int emulate_popcntb_inst(struct pt_regs *regs, u32 instword) { u32 ra,rs; unsigned long tmp; ra = (instword >> 16) & 0x1f; rs = (instword >> 21) & 0x1f; tmp = regs->gpr[rs]; tmp = tmp - ((tmp >> 1) & 0x5555555555555555ULL); tmp = (tmp & 0x3333333333333333ULL) + ((tmp >> 2) & 0x3333333333333333ULL); tmp = (tmp + (tmp >> 4)) & 0x0f0f0f0f0f0f0f0fULL; regs->gpr[ra] = tmp; return 0; } static int emulate_isel(struct pt_regs *regs, u32 instword) { u8 rT = (instword >> 21) & 0x1f; u8 rA = (instword >> 16) & 0x1f; u8 rB = (instword >> 11) & 0x1f; u8 BC = (instword >> 6) & 0x1f; u8 bit; unsigned long tmp; tmp = (rA == 0) ? 0 : regs->gpr[rA]; bit = (regs->ccr >> (31 - BC)) & 0x1; regs->gpr[rT] = bit ? tmp : regs->gpr[rB]; return 0; } #ifdef CONFIG_PPC_TRANSACTIONAL_MEM static inline bool tm_abort_check(struct pt_regs *regs, int cause) { /* If we're emulating a load/store in an active transaction, we cannot * emulate it as the kernel operates in transaction suspended context. * We need to abort the transaction. This creates a persistent TM * abort so tell the user what caused it with a new code. */ if (MSR_TM_TRANSACTIONAL(regs->msr)) { tm_enable(); tm_abort(cause); return true; } return false; } #else static inline bool tm_abort_check(struct pt_regs *regs, int reason) { return false; } #endif static int emulate_instruction(struct pt_regs *regs) { u32 instword; u32 rd; if (!user_mode(regs)) return -EINVAL; CHECK_FULL_REGS(regs); if (get_user(instword, (u32 __user *)(regs->nip))) return -EFAULT; /* Emulate the mfspr rD, PVR. */ if ((instword & PPC_INST_MFSPR_PVR_MASK) == PPC_INST_MFSPR_PVR) { PPC_WARN_EMULATED(mfpvr, regs); rd = (instword >> 21) & 0x1f; regs->gpr[rd] = mfspr(SPRN_PVR); return 0; } /* Emulating the dcba insn is just a no-op. */ if ((instword & PPC_INST_DCBA_MASK) == PPC_INST_DCBA) { PPC_WARN_EMULATED(dcba, regs); return 0; } /* Emulate the mcrxr insn. */ if ((instword & PPC_INST_MCRXR_MASK) == PPC_INST_MCRXR) { int shift = (instword >> 21) & 0x1c; unsigned long msk = 0xf0000000UL >> shift; PPC_WARN_EMULATED(mcrxr, regs); regs->ccr = (regs->ccr & ~msk) | ((regs->xer >> shift) & msk); regs->xer &= ~0xf0000000UL; return 0; } /* Emulate load/store string insn. */ if ((instword & PPC_INST_STRING_GEN_MASK) == PPC_INST_STRING) { if (tm_abort_check(regs, TM_CAUSE_EMULATE | TM_CAUSE_PERSISTENT)) return -EINVAL; PPC_WARN_EMULATED(string, regs); return emulate_string_inst(regs, instword); } /* Emulate the popcntb (Population Count Bytes) instruction. */ if ((instword & PPC_INST_POPCNTB_MASK) == PPC_INST_POPCNTB) { PPC_WARN_EMULATED(popcntb, regs); return emulate_popcntb_inst(regs, instword); } /* Emulate isel (Integer Select) instruction */ if ((instword & PPC_INST_ISEL_MASK) == PPC_INST_ISEL) { PPC_WARN_EMULATED(isel, regs); return emulate_isel(regs, instword); } /* Emulate sync instruction variants */ if ((instword & PPC_INST_SYNC_MASK) == PPC_INST_SYNC) { PPC_WARN_EMULATED(sync, regs); asm volatile("sync"); return 0; } #ifdef CONFIG_PPC64 /* Emulate the mfspr rD, DSCR. */ if ((((instword & PPC_INST_MFSPR_DSCR_USER_MASK) == PPC_INST_MFSPR_DSCR_USER) || ((instword & PPC_INST_MFSPR_DSCR_MASK) == PPC_INST_MFSPR_DSCR)) && cpu_has_feature(CPU_FTR_DSCR)) { PPC_WARN_EMULATED(mfdscr, regs); rd = (instword >> 21) & 0x1f; regs->gpr[rd] = mfspr(SPRN_DSCR); return 0; } /* Emulate the mtspr DSCR, rD. */ if ((((instword & PPC_INST_MTSPR_DSCR_USER_MASK) == PPC_INST_MTSPR_DSCR_USER) || ((instword & PPC_INST_MTSPR_DSCR_MASK) == PPC_INST_MTSPR_DSCR)) && cpu_has_feature(CPU_FTR_DSCR)) { PPC_WARN_EMULATED(mtdscr, regs); rd = (instword >> 21) & 0x1f; current->thread.dscr = regs->gpr[rd]; current->thread.dscr_inherit = 1; mtspr(SPRN_DSCR, current->thread.dscr); return 0; } #endif return -EINVAL; } int is_valid_bugaddr(unsigned long addr) { return is_kernel_addr(addr); } #ifdef CONFIG_MATH_EMULATION static int emulate_math(struct pt_regs *regs) { int ret; extern int do_mathemu(struct pt_regs *regs); ret = do_mathemu(regs); if (ret >= 0) PPC_WARN_EMULATED(math, regs); switch (ret) { case 0: emulate_single_step(regs); return 0; case 1: { int code = 0; code = __parse_fpscr(current->thread.fp_state.fpscr); _exception(SIGFPE, regs, code, regs->nip); return 0; } case -EFAULT: _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); return 0; } return -1; } #else static inline int emulate_math(struct pt_regs *regs) { return -1; } #endif void program_check_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); unsigned int reason = get_reason(regs); /* We can now get here via a FP Unavailable exception if the core * has no FPU, in that case the reason flags will be 0 */ if (reason & REASON_FP) { /* IEEE FP exception */ parse_fpe(regs); goto bail; } if (reason & REASON_TRAP) { unsigned long bugaddr; /* Debugger is first in line to stop recursive faults in * rcu_lock, notify_die, or atomic_notifier_call_chain */ if (debugger_bpt(regs)) goto bail; if (kprobe_handler(regs)) goto bail; /* trap exception */ if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP) == NOTIFY_STOP) goto bail; bugaddr = regs->nip; /* * Fixup bugaddr for BUG_ON() in real mode */ if (!is_kernel_addr(bugaddr) && !(regs->msr & MSR_IR)) bugaddr += PAGE_OFFSET; if (!(regs->msr & MSR_PR) && /* not user-mode */ report_bug(bugaddr, regs) == BUG_TRAP_TYPE_WARN) { regs->nip += 4; goto bail; } _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip); goto bail; } #ifdef CONFIG_PPC_TRANSACTIONAL_MEM if (reason & REASON_TM) { /* This is a TM "Bad Thing Exception" program check. * This occurs when: * - An rfid/hrfid/mtmsrd attempts to cause an illegal * transition in TM states. * - A trechkpt is attempted when transactional. * - A treclaim is attempted when non transactional. * - A tend is illegally attempted. * - writing a TM SPR when transactional. */ if (!user_mode(regs) && report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) { regs->nip += 4; goto bail; } /* If usermode caused this, it's done something illegal and * gets a SIGILL slap on the wrist. We call it an illegal * operand to distinguish from the instruction just being bad * (e.g. executing a 'tend' on a CPU without TM!); it's an * illegal /placement/ of a valid instruction. */ if (user_mode(regs)) { _exception(SIGILL, regs, ILL_ILLOPN, regs->nip); goto bail; } else { printk(KERN_EMERG "Unexpected TM Bad Thing exception " "at %lx (msr 0x%x)\n", regs->nip, reason); die("Unrecoverable exception", regs, SIGABRT); } } #endif /* * If we took the program check in the kernel skip down to sending a * SIGILL. The subsequent cases all relate to emulating instructions * which we should only do for userspace. We also do not want to enable * interrupts for kernel faults because that might lead to further * faults, and loose the context of the original exception. */ if (!user_mode(regs)) goto sigill; /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); /* (reason & REASON_ILLEGAL) would be the obvious thing here, * but there seems to be a hardware bug on the 405GP (RevD) * that means ESR is sometimes set incorrectly - either to * ESR_DST (!?) or 0. In the process of chasing this with the * hardware people - not sure if it can happen on any illegal * instruction or only on FP instructions, whether there is a * pattern to occurrences etc. -dgibson 31/Mar/2003 */ if (!emulate_math(regs)) goto bail; /* Try to emulate it if we should. */ if (reason & (REASON_ILLEGAL | REASON_PRIVILEGED)) { switch (emulate_instruction(regs)) { case 0: regs->nip += 4; emulate_single_step(regs); goto bail; case -EFAULT: _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); goto bail; } } sigill: if (reason & REASON_PRIVILEGED) _exception(SIGILL, regs, ILL_PRVOPC, regs->nip); else _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); bail: exception_exit(prev_state); } NOKPROBE_SYMBOL(program_check_exception); /* * This occurs when running in hypervisor mode on POWER6 or later * and an illegal instruction is encountered. */ void emulation_assist_interrupt(struct pt_regs *regs) { regs->msr |= REASON_ILLEGAL; program_check_exception(regs); } NOKPROBE_SYMBOL(emulation_assist_interrupt); void alignment_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); int sig, code, fixed = 0; /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); if (tm_abort_check(regs, TM_CAUSE_ALIGNMENT | TM_CAUSE_PERSISTENT)) goto bail; /* we don't implement logging of alignment exceptions */ if (!(current->thread.align_ctl & PR_UNALIGN_SIGBUS)) fixed = fix_alignment(regs); if (fixed == 1) { regs->nip += 4; /* skip over emulated instruction */ emulate_single_step(regs); goto bail; } /* Operand address was bad */ if (fixed == -EFAULT) { sig = SIGSEGV; code = SEGV_ACCERR; } else { sig = SIGBUS; code = BUS_ADRALN; } if (user_mode(regs)) _exception(sig, regs, code, regs->dar); else bad_page_fault(regs, regs->dar, sig); bail: exception_exit(prev_state); } void slb_miss_bad_addr(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); if (user_mode(regs)) _exception(SIGSEGV, regs, SEGV_BNDERR, regs->dar); else bad_page_fault(regs, regs->dar, SIGSEGV); exception_exit(prev_state); } void StackOverflow(struct pt_regs *regs) { printk(KERN_CRIT "Kernel stack overflow in process %p, r1=%lx\n", current, regs->gpr[1]); debugger(regs); show_regs(regs); panic("kernel stack overflow"); } void nonrecoverable_exception(struct pt_regs *regs) { printk(KERN_ERR "Non-recoverable exception at PC=%lx MSR=%lx\n", regs->nip, regs->msr); debugger(regs); die("nonrecoverable exception", regs, SIGKILL); } void kernel_fp_unavailable_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); printk(KERN_EMERG "Unrecoverable FP Unavailable Exception " "%lx at %lx\n", regs->trap, regs->nip); die("Unrecoverable FP Unavailable Exception", regs, SIGABRT); exception_exit(prev_state); } void altivec_unavailable_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); if (user_mode(regs)) { /* A user program has executed an altivec instruction, but this kernel doesn't support altivec. */ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); goto bail; } printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception " "%lx at %lx\n", regs->trap, regs->nip); die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT); bail: exception_exit(prev_state); } void vsx_unavailable_exception(struct pt_regs *regs) { if (user_mode(regs)) { /* A user program has executed an vsx instruction, but this kernel doesn't support vsx. */ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); return; } printk(KERN_EMERG "Unrecoverable VSX Unavailable Exception " "%lx at %lx\n", regs->trap, regs->nip); die("Unrecoverable VSX Unavailable Exception", regs, SIGABRT); } #ifdef CONFIG_PPC64 static void tm_unavailable(struct pt_regs *regs) { #ifdef CONFIG_PPC_TRANSACTIONAL_MEM if (user_mode(regs)) { current->thread.load_tm++; regs->msr |= MSR_TM; tm_enable(); tm_restore_sprs(¤t->thread); return; } #endif pr_emerg("Unrecoverable TM Unavailable Exception " "%lx at %lx\n", regs->trap, regs->nip); die("Unrecoverable TM Unavailable Exception", regs, SIGABRT); } void facility_unavailable_exception(struct pt_regs *regs) { static char *facility_strings[] = { [FSCR_FP_LG] = "FPU", [FSCR_VECVSX_LG] = "VMX/VSX", [FSCR_DSCR_LG] = "DSCR", [FSCR_PM_LG] = "PMU SPRs", [FSCR_BHRB_LG] = "BHRB", [FSCR_TM_LG] = "TM", [FSCR_EBB_LG] = "EBB", [FSCR_TAR_LG] = "TAR", [FSCR_MSGP_LG] = "MSGP", }; char *facility = "unknown"; u64 value; u32 instword, rd; u8 status; bool hv; hv = (regs->trap == 0xf80); if (hv) value = mfspr(SPRN_HFSCR); else value = mfspr(SPRN_FSCR); status = value >> 56; if (status == FSCR_DSCR_LG) { /* * User is accessing the DSCR register using the problem * state only SPR number (0x03) either through a mfspr or * a mtspr instruction. If it is a write attempt through * a mtspr, then we set the inherit bit. This also allows * the user to write or read the register directly in the * future by setting via the FSCR DSCR bit. But in case it * is a read DSCR attempt through a mfspr instruction, we * just emulate the instruction instead. This code path will * always emulate all the mfspr instructions till the user * has attempted at least one mtspr instruction. This way it * preserves the same behaviour when the user is accessing * the DSCR through privilege level only SPR number (0x11) * which is emulated through illegal instruction exception. * We always leave HFSCR DSCR set. */ if (get_user(instword, (u32 __user *)(regs->nip))) { pr_err("Failed to fetch the user instruction\n"); return; } /* Write into DSCR (mtspr 0x03, RS) */ if ((instword & PPC_INST_MTSPR_DSCR_USER_MASK) == PPC_INST_MTSPR_DSCR_USER) { rd = (instword >> 21) & 0x1f; current->thread.dscr = regs->gpr[rd]; current->thread.dscr_inherit = 1; current->thread.fscr |= FSCR_DSCR; mtspr(SPRN_FSCR, current->thread.fscr); } /* Read from DSCR (mfspr RT, 0x03) */ if ((instword & PPC_INST_MFSPR_DSCR_USER_MASK) == PPC_INST_MFSPR_DSCR_USER) { if (emulate_instruction(regs)) { pr_err("DSCR based mfspr emulation failed\n"); return; } regs->nip += 4; emulate_single_step(regs); } return; } if (status == FSCR_TM_LG) { /* * If we're here then the hardware is TM aware because it * generated an exception with FSRM_TM set. * * If cpu_has_feature(CPU_FTR_TM) is false, then either firmware * told us not to do TM, or the kernel is not built with TM * support. * * If both of those things are true, then userspace can spam the * console by triggering the printk() below just by continually * doing tbegin (or any TM instruction). So in that case just * send the process a SIGILL immediately. */ if (!cpu_has_feature(CPU_FTR_TM)) goto out; tm_unavailable(regs); return; } if ((hv || status >= 2) && (status < ARRAY_SIZE(facility_strings)) && facility_strings[status]) facility = facility_strings[status]; /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); pr_err_ratelimited("%sFacility '%s' unavailable (%d), exception at 0x%lx, MSR=%lx\n", hv ? "Hypervisor " : "", facility, status, regs->nip, regs->msr); out: if (user_mode(regs)) { _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); return; } die("Unexpected facility unavailable exception", regs, SIGABRT); } #endif #ifdef CONFIG_PPC_TRANSACTIONAL_MEM void fp_unavailable_tm(struct pt_regs *regs) { /* Note: This does not handle any kind of FP laziness. */ TM_DEBUG("FP Unavailable trap whilst transactional at 0x%lx, MSR=%lx\n", regs->nip, regs->msr); /* We can only have got here if the task started using FP after * beginning the transaction. So, the transactional regs are just a * copy of the checkpointed ones. But, we still need to recheckpoint * as we're enabling FP for the process; it will return, abort the * transaction, and probably retry but now with FP enabled. So the * checkpointed FP registers need to be loaded. */ tm_reclaim_current(TM_CAUSE_FAC_UNAV); /* Reclaim didn't save out any FPRs to transact_fprs. */ /* Enable FP for the task: */ regs->msr |= (MSR_FP | current->thread.fpexc_mode); /* This loads and recheckpoints the FP registers from * thread.fpr[]. They will remain in registers after the * checkpoint so we don't need to reload them after. * If VMX is in use, the VRs now hold checkpointed values, * so we don't want to load the VRs from the thread_struct. */ tm_recheckpoint(¤t->thread, MSR_FP); /* If VMX is in use, get the transactional values back */ if (regs->msr & MSR_VEC) { msr_check_and_set(MSR_VEC); load_vr_state(¤t->thread.vr_state); /* At this point all the VSX state is loaded, so enable it */ regs->msr |= MSR_VSX; } } void altivec_unavailable_tm(struct pt_regs *regs) { /* See the comments in fp_unavailable_tm(). This function operates * the same way. */ TM_DEBUG("Vector Unavailable trap whilst transactional at 0x%lx," "MSR=%lx\n", regs->nip, regs->msr); tm_reclaim_current(TM_CAUSE_FAC_UNAV); regs->msr |= MSR_VEC; tm_recheckpoint(¤t->thread, MSR_VEC); current->thread.used_vr = 1; if (regs->msr & MSR_FP) { msr_check_and_set(MSR_FP); load_fp_state(¤t->thread.fp_state); regs->msr |= MSR_VSX; } } void vsx_unavailable_tm(struct pt_regs *regs) { unsigned long orig_msr = regs->msr; /* See the comments in fp_unavailable_tm(). This works similarly, * though we're loading both FP and VEC registers in here. * * If FP isn't in use, load FP regs. If VEC isn't in use, load VEC * regs. Either way, set MSR_VSX. */ TM_DEBUG("VSX Unavailable trap whilst transactional at 0x%lx," "MSR=%lx\n", regs->nip, regs->msr); current->thread.used_vsr = 1; /* If FP and VMX are already loaded, we have all the state we need */ if ((orig_msr & (MSR_FP | MSR_VEC)) == (MSR_FP | MSR_VEC)) { regs->msr |= MSR_VSX; return; } /* This reclaims FP and/or VR regs if they're already enabled */ tm_reclaim_current(TM_CAUSE_FAC_UNAV); regs->msr |= MSR_VEC | MSR_FP | current->thread.fpexc_mode | MSR_VSX; /* This loads & recheckpoints FP and VRs; but we have * to be sure not to overwrite previously-valid state. */ tm_recheckpoint(¤t->thread, regs->msr & ~orig_msr); msr_check_and_set(orig_msr & (MSR_FP | MSR_VEC)); if (orig_msr & MSR_FP) load_fp_state(¤t->thread.fp_state); if (orig_msr & MSR_VEC) load_vr_state(¤t->thread.vr_state); } #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ void performance_monitor_exception(struct pt_regs *regs) { __this_cpu_inc(irq_stat.pmu_irqs); perf_irq(regs); } #ifdef CONFIG_8xx void SoftwareEmulation(struct pt_regs *regs) { CHECK_FULL_REGS(regs); if (!user_mode(regs)) { debugger(regs); die("Kernel Mode Unimplemented Instruction or SW FPU Emulation", regs, SIGFPE); } if (!emulate_math(regs)) return; _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); } #endif /* CONFIG_8xx */ #ifdef CONFIG_PPC_ADV_DEBUG_REGS static void handle_debug(struct pt_regs *regs, unsigned long debug_status) { int changed = 0; /* * Determine the cause of the debug event, clear the * event flags and send a trap to the handler. Torez */ if (debug_status & (DBSR_DAC1R | DBSR_DAC1W)) { dbcr_dac(current) &= ~(DBCR_DAC1R | DBCR_DAC1W); #ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE current->thread.debug.dbcr2 &= ~DBCR2_DAC12MODE; #endif do_send_trap(regs, mfspr(SPRN_DAC1), debug_status, TRAP_HWBKPT, 5); changed |= 0x01; } else if (debug_status & (DBSR_DAC2R | DBSR_DAC2W)) { dbcr_dac(current) &= ~(DBCR_DAC2R | DBCR_DAC2W); do_send_trap(regs, mfspr(SPRN_DAC2), debug_status, TRAP_HWBKPT, 6); changed |= 0x01; } else if (debug_status & DBSR_IAC1) { current->thread.debug.dbcr0 &= ~DBCR0_IAC1; dbcr_iac_range(current) &= ~DBCR_IAC12MODE; do_send_trap(regs, mfspr(SPRN_IAC1), debug_status, TRAP_HWBKPT, 1); changed |= 0x01; } else if (debug_status & DBSR_IAC2) { current->thread.debug.dbcr0 &= ~DBCR0_IAC2; do_send_trap(regs, mfspr(SPRN_IAC2), debug_status, TRAP_HWBKPT, 2); changed |= 0x01; } else if (debug_status & DBSR_IAC3) { current->thread.debug.dbcr0 &= ~DBCR0_IAC3; dbcr_iac_range(current) &= ~DBCR_IAC34MODE; do_send_trap(regs, mfspr(SPRN_IAC3), debug_status, TRAP_HWBKPT, 3); changed |= 0x01; } else if (debug_status & DBSR_IAC4) { current->thread.debug.dbcr0 &= ~DBCR0_IAC4; do_send_trap(regs, mfspr(SPRN_IAC4), debug_status, TRAP_HWBKPT, 4); changed |= 0x01; } /* * At the point this routine was called, the MSR(DE) was turned off. * Check all other debug flags and see if that bit needs to be turned * back on or not. */ if (DBCR_ACTIVE_EVENTS(current->thread.debug.dbcr0, current->thread.debug.dbcr1)) regs->msr |= MSR_DE; else /* Make sure the IDM flag is off */ current->thread.debug.dbcr0 &= ~DBCR0_IDM; if (changed & 0x01) mtspr(SPRN_DBCR0, current->thread.debug.dbcr0); } void DebugException(struct pt_regs *regs, unsigned long debug_status) { current->thread.debug.dbsr = debug_status; /* Hack alert: On BookE, Branch Taken stops on the branch itself, while * on server, it stops on the target of the branch. In order to simulate * the server behaviour, we thus restart right away with a single step * instead of stopping here when hitting a BT */ if (debug_status & DBSR_BT) { regs->msr &= ~MSR_DE; /* Disable BT */ mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_BT); /* Clear the BT event */ mtspr(SPRN_DBSR, DBSR_BT); /* Do the single step trick only when coming from userspace */ if (user_mode(regs)) { current->thread.debug.dbcr0 &= ~DBCR0_BT; current->thread.debug.dbcr0 |= DBCR0_IDM | DBCR0_IC; regs->msr |= MSR_DE; return; } if (kprobe_post_handler(regs)) return; if (notify_die(DIE_SSTEP, "block_step", regs, 5, 5, SIGTRAP) == NOTIFY_STOP) { return; } if (debugger_sstep(regs)) return; } else if (debug_status & DBSR_IC) { /* Instruction complete */ regs->msr &= ~MSR_DE; /* Disable instruction completion */ mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_IC); /* Clear the instruction completion event */ mtspr(SPRN_DBSR, DBSR_IC); if (kprobe_post_handler(regs)) return; if (notify_die(DIE_SSTEP, "single_step", regs, 5, 5, SIGTRAP) == NOTIFY_STOP) { return; } if (debugger_sstep(regs)) return; if (user_mode(regs)) { current->thread.debug.dbcr0 &= ~DBCR0_IC; if (DBCR_ACTIVE_EVENTS(current->thread.debug.dbcr0, current->thread.debug.dbcr1)) regs->msr |= MSR_DE; else /* Make sure the IDM bit is off */ current->thread.debug.dbcr0 &= ~DBCR0_IDM; } _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip); } else handle_debug(regs, debug_status); } NOKPROBE_SYMBOL(DebugException); #endif /* CONFIG_PPC_ADV_DEBUG_REGS */ #if !defined(CONFIG_TAU_INT) void TAUException(struct pt_regs *regs) { printk("TAU trap at PC: %lx, MSR: %lx, vector=%lx %s\n", regs->nip, regs->msr, regs->trap, print_tainted()); } #endif /* CONFIG_INT_TAU */ #ifdef CONFIG_ALTIVEC void altivec_assist_exception(struct pt_regs *regs) { int err; if (!user_mode(regs)) { printk(KERN_EMERG "VMX/Altivec assist exception in kernel mode" " at %lx\n", regs->nip); die("Kernel VMX/Altivec assist exception", regs, SIGILL); } flush_altivec_to_thread(current); PPC_WARN_EMULATED(altivec, regs); err = emulate_altivec(regs); if (err == 0) { regs->nip += 4; /* skip emulated instruction */ emulate_single_step(regs); return; } if (err == -EFAULT) { /* got an error reading the instruction */ _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip); } else { /* didn't recognize the instruction */ /* XXX quick hack for now: set the non-Java bit in the VSCR */ printk_ratelimited(KERN_ERR "Unrecognized altivec instruction " "in %s at %lx\n", current->comm, regs->nip); current->thread.vr_state.vscr.u[3] |= 0x10000; } } #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_FSL_BOOKE void CacheLockingException(struct pt_regs *regs, unsigned long address, unsigned long error_code) { /* We treat cache locking instructions from the user * as priv ops, in the future we could try to do * something smarter */ if (error_code & (ESR_DLK|ESR_ILK)) _exception(SIGILL, regs, ILL_PRVOPC, regs->nip); return; } #endif /* CONFIG_FSL_BOOKE */ #ifdef CONFIG_SPE void SPEFloatingPointException(struct pt_regs *regs) { extern int do_spe_mathemu(struct pt_regs *regs); unsigned long spefscr; int fpexc_mode; int code = 0; int err; flush_spe_to_thread(current); spefscr = current->thread.spefscr; fpexc_mode = current->thread.fpexc_mode; if ((spefscr & SPEFSCR_FOVF) && (fpexc_mode & PR_FP_EXC_OVF)) { code = FPE_FLTOVF; } else if ((spefscr & SPEFSCR_FUNF) && (fpexc_mode & PR_FP_EXC_UND)) { code = FPE_FLTUND; } else if ((spefscr & SPEFSCR_FDBZ) && (fpexc_mode & PR_FP_EXC_DIV)) code = FPE_FLTDIV; else if ((spefscr & SPEFSCR_FINV) && (fpexc_mode & PR_FP_EXC_INV)) { code = FPE_FLTINV; } else if ((spefscr & (SPEFSCR_FG | SPEFSCR_FX)) && (fpexc_mode & PR_FP_EXC_RES)) code = FPE_FLTRES; err = do_spe_mathemu(regs); if (err == 0) { regs->nip += 4; /* skip emulated instruction */ emulate_single_step(regs); return; } if (err == -EFAULT) { /* got an error reading the instruction */ _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip); } else if (err == -EINVAL) { /* didn't recognize the instruction */ printk(KERN_ERR "unrecognized spe instruction " "in %s at %lx\n", current->comm, regs->nip); } else { _exception(SIGFPE, regs, code, regs->nip); } return; } void SPEFloatingPointRoundException(struct pt_regs *regs) { extern int speround_handler(struct pt_regs *regs); int err; preempt_disable(); if (regs->msr & MSR_SPE) giveup_spe(current); preempt_enable(); regs->nip -= 4; err = speround_handler(regs); if (err == 0) { regs->nip += 4; /* skip emulated instruction */ emulate_single_step(regs); return; } if (err == -EFAULT) { /* got an error reading the instruction */ _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip); } else if (err == -EINVAL) { /* didn't recognize the instruction */ printk(KERN_ERR "unrecognized spe instruction " "in %s at %lx\n", current->comm, regs->nip); } else { _exception(SIGFPE, regs, 0, regs->nip); return; } } #endif /* * We enter here if we get an unrecoverable exception, that is, one * that happened at a point where the RI (recoverable interrupt) bit * in the MSR is 0. This indicates that SRR0/1 are live, and that * we therefore lost state by taking this exception. */ void unrecoverable_exception(struct pt_regs *regs) { printk(KERN_EMERG "Unrecoverable exception %lx at %lx\n", regs->trap, regs->nip); die("Unrecoverable exception", regs, SIGABRT); } #if defined(CONFIG_BOOKE_WDT) || defined(CONFIG_40x) /* * Default handler for a Watchdog exception, * spins until a reboot occurs */ void __attribute__ ((weak)) WatchdogHandler(struct pt_regs *regs) { /* Generic WatchdogHandler, implement your own */ mtspr(SPRN_TCR, mfspr(SPRN_TCR)&(~TCR_WIE)); return; } void WatchdogException(struct pt_regs *regs) { printk (KERN_EMERG "PowerPC Book-E Watchdog Exception\n"); WatchdogHandler(regs); } #endif /* * We enter here if we discover during exception entry that we are * running in supervisor mode with a userspace value in the stack pointer. */ void kernel_bad_stack(struct pt_regs *regs) { printk(KERN_EMERG "Bad kernel stack pointer %lx at %lx\n", regs->gpr[1], regs->nip); die("Bad kernel stack pointer", regs, SIGABRT); } void __init trap_init(void) { } #ifdef CONFIG_PPC_EMULATED_STATS #define WARN_EMULATED_SETUP(type) .type = { .name = #type } struct ppc_emulated ppc_emulated = { #ifdef CONFIG_ALTIVEC WARN_EMULATED_SETUP(altivec), #endif WARN_EMULATED_SETUP(dcba), WARN_EMULATED_SETUP(dcbz), WARN_EMULATED_SETUP(fp_pair), WARN_EMULATED_SETUP(isel), WARN_EMULATED_SETUP(mcrxr), WARN_EMULATED_SETUP(mfpvr), WARN_EMULATED_SETUP(multiple), WARN_EMULATED_SETUP(popcntb), WARN_EMULATED_SETUP(spe), WARN_EMULATED_SETUP(string), WARN_EMULATED_SETUP(sync), WARN_EMULATED_SETUP(unaligned), #ifdef CONFIG_MATH_EMULATION WARN_EMULATED_SETUP(math), #endif #ifdef CONFIG_VSX WARN_EMULATED_SETUP(vsx), #endif #ifdef CONFIG_PPC64 WARN_EMULATED_SETUP(mfdscr), WARN_EMULATED_SETUP(mtdscr), WARN_EMULATED_SETUP(lq_stq), #endif }; u32 ppc_warn_emulated; void ppc_warn_emulated_print(const char *type) { pr_warn_ratelimited("%s used emulated %s instruction\n", current->comm, type); } static int __init ppc_warn_emulated_init(void) { struct dentry *dir, *d; unsigned int i; struct ppc_emulated_entry *entries = (void *)&ppc_emulated; if (!powerpc_debugfs_root) return -ENODEV; dir = debugfs_create_dir("emulated_instructions", powerpc_debugfs_root); if (!dir) return -ENOMEM; d = debugfs_create_u32("do_warn", S_IRUGO | S_IWUSR, dir, &ppc_warn_emulated); if (!d) goto fail; for (i = 0; i < sizeof(ppc_emulated)/sizeof(*entries); i++) { d = debugfs_create_u32(entries[i].name, S_IRUGO | S_IWUSR, dir, (u32 *)&entries[i].val.counter); if (!d) goto fail; } return 0; fail: debugfs_remove_recursive(dir); return -ENOMEM; } device_initcall(ppc_warn_emulated_init); #endif /* CONFIG_PPC_EMULATED_STATS */