From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/ppc64/kernel/traps.c | 565 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 565 insertions(+) create mode 100644 arch/ppc64/kernel/traps.c (limited to 'arch/ppc64/kernel/traps.c') diff --git a/arch/ppc64/kernel/traps.c b/arch/ppc64/kernel/traps.c new file mode 100644 index 00000000000..10fc61f3f6a --- /dev/null +++ b/arch/ppc64/kernel/traps.c @@ -0,0 +1,565 @@ +/* + * linux/arch/ppc64/kernel/traps.c + * + * 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@cs.anu.edu.au) + */ + +/* + * This file handles the architecture-dependent parts of hardware exceptions + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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 *ppc64_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(&ppc64_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); + 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 + 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; + } + 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) { + printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n"); + ssleep(5); + panic("Fatal exception"); + } + do_exit(SIGSEGV); + + 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); +} + +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, 0); + + /* 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. */ +} + +void machine_check_exception(struct pt_regs *regs) +{ + 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; + + if (debugger_fault_handler(regs)) + return; + die("Machine check", regs, 0); + + /* Must die if the interrupt is not recoverable */ + if (!(regs->msr & MSR_RI)) + panic("Unrecoverable Machine check"); +} + +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 single_step_exception(struct pt_regs *regs) +{ + regs->msr &= ~MSR_SE; /* Turn off 'trace' bit */ + + 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 inline void emulate_single_step(struct pt_regs *regs) +{ + if (regs->msr & MSR_SE) + single_step_exception(regs); +} + +static void parse_fpe(struct pt_regs *regs) +{ + int code = 0; + unsigned long fpscr; + + flush_fp_to_thread(current); + + fpscr = current->thread.fpscr; + + /* 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. Return non-zero if we can't + * emulate, or -EFAULT if the associated memory access caused an access + * fault. Return zero on success. + */ + +#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 + +static int emulate_instruction(struct pt_regs *regs) +{ + unsigned int instword; + + if (!user_mode(regs)) + return -EINVAL; + + CHECK_FULL_REGS(regs); + + if (get_user(instword, (unsigned int __user *)(regs->nip))) + return -EFAULT; + + /* Emulate the mfspr rD, PVR. */ + if ((instword & INST_MFSPR_PVR_MASK) == INST_MFSPR_PVR) { + unsigned int rd; + + 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) { + static int warned; + + if (!warned) { + printk(KERN_WARNING + "process %d (%s) uses obsolete 'dcba' insn\n", + current->pid, current->comm); + warned = 1; + } + return 0; + } + + /* Emulate the mcrxr insn. */ + if ((instword & INST_MCRXR_MASK) == INST_MCRXR) { + static int warned; + unsigned int shift; + + if (!warned) { + printk(KERN_WARNING + "process %d (%s) uses obsolete 'mcrxr' insn\n", + current->pid, current->comm); + warned = 1; + } + + shift = (instword >> 21) & 0x1c; + regs->ccr &= ~(0xf0000000 >> shift); + regs->ccr |= (regs->xer & 0xf0000000) >> shift; + regs->xer &= ~0xf0000000; + return 0; + } + + 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 */ + printk(KERN_ERR "Badness in %s at %s:%d\n", + bug->function, bug->file, + (unsigned int)bug->line & ~BUG_WARNING_TRAP); + show_stack(current, (void *)regs->gpr[1]); + return 1; + } + printk(KERN_CRIT "kernel BUG in %s at %s:%d!\n", + bug->function, bug->file, (unsigned int)bug->line); + return 0; +} + +void program_check_exception(struct pt_regs *regs) +{ + if (debugger_fault_handler(regs)) + return; + + if (regs->msr & 0x100000) { + /* IEEE FP exception */ + parse_fpe(regs); + } else if (regs->msr & 0x20000) { + /* 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); + + } else { + /* Privileged or illegal instruction; try to emulate it. */ + switch (emulate_instruction(regs)) { + case 0: + regs->nip += 4; + emulate_single_step(regs); + break; + + case -EFAULT: + _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); + break; + + default: + if (regs->msr & 0x40000) + /* priveleged */ + _exception(SIGILL, regs, ILL_PRVOPC, regs->nip); + else + /* illegal */ + _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); + break; + } + } +} + +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) +{ +#ifndef 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); +} + +extern perf_irq_t perf_irq; + +void performance_monitor_exception(struct pt_regs *regs) +{ + perf_irq(regs); +} + +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_MAPERR, regs->dar); + } else { + /* Search exception table */ + bad_page_fault(regs, regs->dar, SIGSEGV); + } + + return; + } + + _exception(SIGBUS, regs, BUS_ADRALN, regs->nip); +} + +#ifdef CONFIG_ALTIVEC +void altivec_assist_exception(struct pt_regs *regs) +{ + int err; + siginfo_t info; + + 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 */ + info.si_signo = SIGSEGV; + info.si_errno = 0; + info.si_code = SEGV_MAPERR; + info.si_addr = (void __user *) regs->nip; + force_sig_info(SIGSEGV, &info, current); + } 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 */ + +/* + * 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); +} + +/* + * 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) +{ +} -- cgit v1.2.3