diff options
Diffstat (limited to 'arch/powerpc/kernel/traps.c')
-rw-r--r-- | arch/powerpc/kernel/traps.c | 1101 |
1 files changed, 1101 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c new file mode 100644 index 000000000000..5d638ecddbd0 --- /dev/null +++ b/arch/powerpc/kernel/traps.c @@ -0,0 +1,1101 @@ +/* + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * 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 <linux/config.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/stddef.h> +#include <linux/unistd.h> +#include <linux/ptrace.h> +#include <linux/slab.h> +#include <linux/user.h> +#include <linux/a.out.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/prctl.h> +#include <linux/delay.h> +#include <linux/kprobes.h> + +#include <asm/kdebug.h> +#include <asm/pgtable.h> +#include <asm/uaccess.h> +#include <asm/system.h> +#include <asm/io.h> +#include <asm/machdep.h> +#include <asm/rtas.h> +#include <asm/xmon.h> +#include <asm/pmc.h> +#ifdef CONFIG_PPC32 +#include <asm/reg.h> +#endif +#ifdef CONFIG_PMAC_BACKLIGHT +#include <asm/backlight.h> +#endif +#ifdef CONFIG_PPC64 +#include <asm/firmware.h> +#include <asm/processor.h> +#include <asm/systemcfg.h> +#endif + +#ifdef CONFIG_PPC64 /* XXX */ +#define _IO_BASE pci_io_base +#endif + +#ifdef CONFIG_DEBUGGER +int (*__debugger)(struct pt_regs *regs); +int (*__debugger_ipi)(struct pt_regs *regs); +int (*__debugger_bpt)(struct pt_regs *regs); +int (*__debugger_sstep)(struct pt_regs *regs); +int (*__debugger_iabr_match)(struct pt_regs *regs); +int (*__debugger_dabr_match)(struct pt_regs *regs); +int (*__debugger_fault_handler)(struct pt_regs *regs); + +EXPORT_SYMBOL(__debugger); +EXPORT_SYMBOL(__debugger_ipi); +EXPORT_SYMBOL(__debugger_bpt); +EXPORT_SYMBOL(__debugger_sstep); +EXPORT_SYMBOL(__debugger_iabr_match); +EXPORT_SYMBOL(__debugger_dabr_match); +EXPORT_SYMBOL(__debugger_fault_handler); +#endif + +struct notifier_block *powerpc_die_chain; +static DEFINE_SPINLOCK(die_notifier_lock); + +int register_die_notifier(struct notifier_block *nb) +{ + int err = 0; + unsigned long flags; + + spin_lock_irqsave(&die_notifier_lock, flags); + err = notifier_chain_register(&powerpc_die_chain, nb); + spin_unlock_irqrestore(&die_notifier_lock, flags); + return err; +} + +/* + * Trap & Exception support + */ + +static DEFINE_SPINLOCK(die_lock); + +int die(const char *str, struct pt_regs *regs, long err) +{ + static int die_counter; + int nl = 0; + + if (debugger(regs)) + return 1; + + console_verbose(); + spin_lock_irq(&die_lock); + bust_spinlocks(1); +#ifdef CONFIG_PMAC_BACKLIGHT + if (_machine == _MACH_Pmac) { + set_backlight_enable(1); + set_backlight_level(BACKLIGHT_MAX); + } +#endif + printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter); +#ifdef CONFIG_PREEMPT + printk("PREEMPT "); + nl = 1; +#endif +#ifdef CONFIG_SMP + printk("SMP NR_CPUS=%d ", NR_CPUS); + nl = 1; +#endif +#ifdef CONFIG_DEBUG_PAGEALLOC + printk("DEBUG_PAGEALLOC "); + nl = 1; +#endif +#ifdef CONFIG_NUMA + printk("NUMA "); + nl = 1; +#endif +#ifdef CONFIG_PPC64 + switch (systemcfg->platform) { + case PLATFORM_PSERIES: + printk("PSERIES "); + nl = 1; + break; + case PLATFORM_PSERIES_LPAR: + printk("PSERIES LPAR "); + nl = 1; + break; + case PLATFORM_ISERIES_LPAR: + printk("ISERIES LPAR "); + nl = 1; + break; + case PLATFORM_POWERMAC: + printk("POWERMAC "); + nl = 1; + break; + case PLATFORM_BPA: + printk("BPA "); + nl = 1; + break; + } +#endif + if (nl) + printk("\n"); + print_modules(); + show_regs(regs); + bust_spinlocks(0); + spin_unlock_irq(&die_lock); + + if (in_interrupt()) + panic("Fatal exception in interrupt"); + + if (panic_on_oops) { +#ifdef CONFIG_PPC64 + printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n"); + ssleep(5); +#endif + panic("Fatal exception"); + } + do_exit(err); + + return 0; +} + +void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) +{ + siginfo_t info; + + if (!user_mode(regs)) { + if (die("Exception in kernel mode", regs, signr)) + return; + } + + 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); + + /* + * Init gets no signals that it doesn't have a handler for. + * That's all very well, but if it has caused a synchronous + * exception and we ignore the resulting signal, it will just + * generate the same exception over and over again and we get + * nowhere. Better to kill it and let the kernel panic. + */ + if (current->pid == 1) { + __sighandler_t handler; + + spin_lock_irq(¤t->sighand->siglock); + handler = current->sighand->action[signr-1].sa.sa_handler; + spin_unlock_irq(¤t->sighand->siglock); + if (handler == SIG_DFL) { + /* init has generated a synchronous exception + and it doesn't have a handler for the signal */ + printk(KERN_CRIT "init has generated signal %d " + "but has no handler for it\n", signr); + do_exit(signr); + } + } +} + +#ifdef CONFIG_PPC64 +void system_reset_exception(struct pt_regs *regs) +{ + /* See if any machine dependent calls */ + if (ppc_md.system_reset_exception) + ppc_md.system_reset_exception(regs); + + 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. */ +} +#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_PPC_PMAC + 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 == 0x60000000) /* nop */ + nip -= 2; + else if (*nip == 0x4c00012c) /* isync */ + --nip; + if (*nip == 0x7c0004ac || (*nip >> 26) == 3) { + /* sync or twi */ + 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 = entry->fixup; + return 1; + } + } +#endif /* CONFIG_PPC_PMAC */ + return 0; +} + +#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) +/* 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.dbcr0 & DBCR0_IC) +#define clear_single_step(regs) (current->thread.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_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 + +/* + * This is "fall-back" implementation for configurations + * which don't provide platform-specific machine check info + */ +void __attribute__ ((weak)) +platform_machine_check(struct pt_regs *regs) +{ +} + +void machine_check_exception(struct pt_regs *regs) +{ +#ifdef CONFIG_PPC64 + int recover = 0; + + /* See if any machine dependent calls */ + if (ppc_md.machine_check_exception) + recover = ppc_md.machine_check_exception(regs); + + if (recover) + return; +#else + unsigned long reason = get_mc_reason(regs); + + if (user_mode(regs)) { + regs->msr |= MSR_RI; + _exception(SIGBUS, regs, BUS_ADRERR, regs->nip); + return; + } + +#if defined(CONFIG_8xx) && defined(CONFIG_PCI) + /* the qspan pci read routines can cause machine checks -- Cort */ + bad_page_fault(regs, regs->dar, SIGBUS); + return; +#endif + + if (debugger_fault_handler(regs)) { + regs->msr |= MSR_RI; + return; + } + + if (check_io_access(regs)) + return; + +#if defined(CONFIG_4xx) && !defined(CONFIG_440A) + if (reason & ESR_IMCP) { + printk("Instruction"); + mtspr(SPRN_ESR, reason & ~ESR_IMCP); + } else + printk("Data"); + printk(" machine check in kernel mode.\n"); +#elif defined(CONFIG_440A) + 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); + } +#elif defined (CONFIG_E500) + 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_GL_CI) + printk("Guarded Load or Cache-Inhibited stwcx.\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 - Read 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"); +#elif defined (CONFIG_E200) + 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"); +#else /* !CONFIG_4xx && !CONFIG_E500 && !CONFIG_E200 */ + 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"); + } +#endif /* CONFIG_4xx */ + + /* + * Optional platform-provided routine to print out + * additional info, e.g. bus error registers. + */ + platform_machine_check(regs); +#endif /* CONFIG_PPC64 */ + + if (debugger_fault_handler(regs)) + return; + die("Machine check", regs, SIGBUS); + + /* Must die if the interrupt is not recoverable */ + if (!(regs->msr & MSR_RI)) + panic("Unrecoverable Machine check"); +} + +void SMIException(struct pt_regs *regs) +{ + die("System Management Interrupt", regs, SIGABRT); +} + +void unknown_exception(struct pt_regs *regs) +{ + printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", + regs->nip, regs->msr, regs->trap); + + _exception(SIGTRAP, regs, 0, 0); +} + +void instruction_breakpoint_exception(struct pt_regs *regs) +{ + if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5, + 5, SIGTRAP) == NOTIFY_STOP) + return; + if (debugger_iabr_match(regs)) + return; + _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip); +} + +void RunModeException(struct pt_regs *regs) +{ + _exception(SIGTRAP, regs, 0, 0); +} + +void __kprobes single_step_exception(struct pt_regs *regs) +{ + regs->msr &= ~(MSR_SE | MSR_BE); /* Turn off 'trace' bits */ + + if (notify_die(DIE_SSTEP, "single_step", regs, 5, + 5, SIGTRAP) == NOTIFY_STOP) + return; + if (debugger_sstep(regs)) + return; + + _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip); +} + +/* + * 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)) { + clear_single_step(regs); + _exception(SIGTRAP, regs, TRAP_TRACE, 0); + } +} + +static void parse_fpe(struct pt_regs *regs) +{ + int code = 0; + unsigned long fpscr; + + flush_fp_to_thread(current); + + fpscr = current->thread.fpscr.val; + + /* Invalid operation */ + if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX)) + code = FPE_FLTINV; + + /* Overflow */ + else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX)) + code = FPE_FLTOVF; + + /* Underflow */ + else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX)) + code = FPE_FLTUND; + + /* Divide by zero */ + else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX)) + code = FPE_FLTDIV; + + /* Inexact result */ + else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX)) + code = FPE_FLTRES; + + _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. + * + */ +#define INST_MFSPR_PVR 0x7c1f42a6 +#define INST_MFSPR_PVR_MASK 0xfc1fffff + +#define INST_DCBA 0x7c0005ec +#define INST_DCBA_MASK 0x7c0007fe + +#define INST_MCRXR 0x7c000400 +#define INST_MCRXR_MASK 0x7c0007fe + +#define INST_STRING 0x7c00042a +#define INST_STRING_MASK 0x7c0007fe +#define INST_STRING_GEN_MASK 0x7c00067e +#define INST_LSWI 0x7c0004aa +#define INST_LSWX 0x7c00042a +#define INST_STSWI 0x7c0005aa +#define INST_STSWX 0x7c00052a + +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 & INST_STRING_MASK) == INST_LSWX) + if ((rT == rA) || (rT == NB_RB)) + return -EINVAL; + + EA = (rA == 0) ? 0 : regs->gpr[rA]; + + switch (instword & INST_STRING_MASK) { + case INST_LSWX: + case INST_STSWX: + EA += NB_RB; + num_bytes = regs->xer & 0x7f; + break; + case INST_LSWI: + case 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)); + + switch ((instword & INST_STRING_MASK)) { + case INST_LSWX: + case 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 INST_STSWI: + case 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_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 & INST_MFSPR_PVR_MASK) == INST_MFSPR_PVR) { + rd = (instword >> 21) & 0x1f; + regs->gpr[rd] = mfspr(SPRN_PVR); + return 0; + } + + /* Emulating the dcba insn is just a no-op. */ + if ((instword & INST_DCBA_MASK) == INST_DCBA) + return 0; + + /* Emulate the mcrxr insn. */ + if ((instword & INST_MCRXR_MASK) == INST_MCRXR) { + int shift = (instword >> 21) & 0x1c; + unsigned long msk = 0xf0000000UL >> shift; + + regs->ccr = (regs->ccr & ~msk) | ((regs->xer >> shift) & msk); + regs->xer &= ~0xf0000000UL; + return 0; + } + + /* Emulate load/store string insn. */ + if ((instword & INST_STRING_GEN_MASK) == INST_STRING) + return emulate_string_inst(regs, instword); + + return -EINVAL; +} + +/* + * Look through the list of trap instructions that are used for BUG(), + * BUG_ON() and WARN_ON() and see if we hit one. At this point we know + * that the exception was caused by a trap instruction of some kind. + * Returns 1 if we should continue (i.e. it was a WARN_ON) or 0 + * otherwise. + */ +extern struct bug_entry __start___bug_table[], __stop___bug_table[]; + +#ifndef CONFIG_MODULES +#define module_find_bug(x) NULL +#endif + +struct bug_entry *find_bug(unsigned long bugaddr) +{ + struct bug_entry *bug; + + for (bug = __start___bug_table; bug < __stop___bug_table; ++bug) + if (bugaddr == bug->bug_addr) + return bug; + return module_find_bug(bugaddr); +} + +static int check_bug_trap(struct pt_regs *regs) +{ + struct bug_entry *bug; + unsigned long addr; + + if (regs->msr & MSR_PR) + return 0; /* not in kernel */ + addr = regs->nip; /* address of trap instruction */ + if (addr < PAGE_OFFSET) + return 0; + bug = find_bug(regs->nip); + if (bug == NULL) + return 0; + if (bug->line & BUG_WARNING_TRAP) { + /* this is a WARN_ON rather than BUG/BUG_ON */ +#ifdef CONFIG_XMON + xmon_printf(KERN_ERR "Badness in %s at %s:%d\n", + bug->function, bug->file, + bug->line & ~BUG_WARNING_TRAP); +#endif /* CONFIG_XMON */ + printk(KERN_ERR "Badness in %s at %s:%d\n", + bug->function, bug->file, + bug->line & ~BUG_WARNING_TRAP); + dump_stack(); + return 1; + } +#ifdef CONFIG_XMON + xmon_printf(KERN_CRIT "kernel BUG in %s at %s:%d!\n", + bug->function, bug->file, bug->line); + xmon(regs); +#endif /* CONFIG_XMON */ + printk(KERN_CRIT "kernel BUG in %s at %s:%d!\n", + bug->function, bug->file, bug->line); + + return 0; +} + +void __kprobes program_check_exception(struct pt_regs *regs) +{ + unsigned int reason = get_reason(regs); + extern int do_mathemu(struct pt_regs *regs); + +#ifdef CONFIG_MATH_EMULATION + /* (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 occurences etc. -dgibson 31/Mar/2003 */ + if (!(reason & REASON_TRAP) && do_mathemu(regs) == 0) { + emulate_single_step(regs); + return; + } +#endif /* CONFIG_MATH_EMULATION */ + + if (reason & REASON_FP) { + /* IEEE FP exception */ + parse_fpe(regs); + return; + } + if (reason & REASON_TRAP) { + /* trap exception */ + if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP) + == NOTIFY_STOP) + return; + if (debugger_bpt(regs)) + return; + if (check_bug_trap(regs)) { + regs->nip += 4; + return; + } + _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip); + return; + } + + /* 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); + return; + case -EFAULT: + _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); + return; + } + } + + if (reason & REASON_PRIVILEGED) + _exception(SIGILL, regs, ILL_PRVOPC, regs->nip); + else + _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); +} + +void alignment_exception(struct pt_regs *regs) +{ + int fixed; + + fixed = fix_alignment(regs); + + if (fixed == 1) { + regs->nip += 4; /* skip over emulated instruction */ + emulate_single_step(regs); + return; + } + + /* Operand address was bad */ + if (fixed == -EFAULT) { + if (user_mode(regs)) + _exception(SIGSEGV, regs, SEGV_ACCERR, regs->dar); + else + /* Search exception table */ + bad_page_fault(regs, regs->dar, SIGSEGV); + return; + } + _exception(SIGBUS, regs, BUS_ADRALN, regs->dar); +} + +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 trace_syscall(struct pt_regs *regs) +{ + printk("Task: %p(%d), PC: %08lX/%08lX, Syscall: %3ld, Result: %s%ld %s\n", + current, current->pid, regs->nip, regs->link, regs->gpr[0], + regs->ccr&0x10000000?"Error=":"", regs->gpr[3], print_tainted()); +} + +void kernel_fp_unavailable_exception(struct pt_regs *regs) +{ + printk(KERN_EMERG "Unrecoverable FP Unavailable Exception " + "%lx at %lx\n", regs->trap, regs->nip); + die("Unrecoverable FP Unavailable Exception", regs, SIGABRT); +} + +void altivec_unavailable_exception(struct pt_regs *regs) +{ +#if !defined(CONFIG_ALTIVEC) + 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); + return; + } +#endif + printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception " + "%lx at %lx\n", regs->trap, regs->nip); + die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT); +} + +#ifdef CONFIG_PPC64 +extern perf_irq_t perf_irq; +#endif + +#if defined(CONFIG_PPC64) || defined(CONFIG_E500) +void performance_monitor_exception(struct pt_regs *regs) +{ + perf_irq(regs); +} +#endif + +#ifdef CONFIG_8xx +void SoftwareEmulation(struct pt_regs *regs) +{ + extern int do_mathemu(struct pt_regs *); + extern int Soft_emulate_8xx(struct pt_regs *); + int errcode; + + CHECK_FULL_REGS(regs); + + if (!user_mode(regs)) { + debugger(regs); + die("Kernel Mode Software FPU Emulation", regs, SIGFPE); + } + +#ifdef CONFIG_MATH_EMULATION + errcode = do_mathemu(regs); +#else + errcode = Soft_emulate_8xx(regs); +#endif + if (errcode) { + if (errcode > 0) + _exception(SIGFPE, regs, 0, 0); + else if (errcode == -EFAULT) + _exception(SIGSEGV, regs, 0, 0); + else + _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); + } else + emulate_single_step(regs); +} +#endif /* CONFIG_8xx */ + +#if defined(CONFIG_40x) || defined(CONFIG_BOOKE) + +void DebugException(struct pt_regs *regs, unsigned long debug_status) +{ + if (debug_status & DBSR_IC) { /* instruction completion */ + regs->msr &= ~MSR_DE; + if (user_mode(regs)) { + current->thread.dbcr0 &= ~DBCR0_IC; + } else { + /* Disable instruction completion */ + mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_IC); + /* Clear the instruction completion event */ + mtspr(SPRN_DBSR, DBSR_IC); + if (debugger_sstep(regs)) + return; + } + _exception(SIGTRAP, regs, TRAP_TRACE, 0); + } +} +#endif /* CONFIG_4xx || CONFIG_BOOKE */ + +#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); + + 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 */ + if (printk_ratelimit()) + printk(KERN_ERR "Unrecognized altivec instruction " + "in %s at %lx\n", current->comm, regs->nip); + current->thread.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) +{ + unsigned long spefscr; + int fpexc_mode; + int code = 0; + + spefscr = current->thread.spefscr; + fpexc_mode = current->thread.fpexc_mode; + + /* Hardware does not neccessarily set sticky + * underflow/overflow/invalid flags */ + if ((spefscr & SPEFSCR_FOVF) && (fpexc_mode & PR_FP_EXC_OVF)) { + code = FPE_FLTOVF; + spefscr |= SPEFSCR_FOVFS; + } + else if ((spefscr & SPEFSCR_FUNF) && (fpexc_mode & PR_FP_EXC_UND)) { + code = FPE_FLTUND; + spefscr |= SPEFSCR_FUNFS; + } + 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; + spefscr |= SPEFSCR_FINVS; + } + else if ((spefscr & (SPEFSCR_FG | SPEFSCR_FX)) && (fpexc_mode & PR_FP_EXC_RES)) + code = FPE_FLTRES; + + current->thread.spefscr = spefscr; + + _exception(SIGFPE, regs, code, 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); +} + +#ifdef CONFIG_BOOKE_WDT +/* + * 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) +{ +} |