forked from Minki/linux
92b4dc1625
The error checking for emulation of load string instructions was overly generous and would cause certain valid forms of the instructions to be treated as illegal. We drop the range checking since the architecture allows this to be boundedly undefined. Tests on CPUs that support these instructions appear not do cause illegal instruction traps on range errors and just allow the execution to occur. Thanks to Kim Phillips for debugging this and figuring out what real HW was doing. Signed-off-by: Kumar Gala <kumar.gala@freescale.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
890 lines
22 KiB
C
890 lines
22 KiB
C
/*
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* arch/ppc/kernel/traps.c
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*
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* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Modified by Cort Dougan (cort@cs.nmt.edu)
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* and Paul Mackerras (paulus@cs.anu.edu.au)
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*/
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/*
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* This file handles the architecture-dependent parts of hardware exceptions
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*/
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#include <linux/errno.h>
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/stddef.h>
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#include <linux/unistd.h>
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#include <linux/ptrace.h>
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#include <linux/slab.h>
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#include <linux/user.h>
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#include <linux/a.out.h>
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#include <linux/interrupt.h>
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#include <linux/config.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/prctl.h>
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#include <asm/pgtable.h>
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#include <asm/uaccess.h>
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#include <asm/system.h>
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#include <asm/io.h>
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#include <asm/reg.h>
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#include <asm/xmon.h>
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#ifdef CONFIG_PMAC_BACKLIGHT
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#include <asm/backlight.h>
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#endif
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#include <asm/perfmon.h>
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#ifdef CONFIG_XMON
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void (*debugger)(struct pt_regs *regs) = xmon;
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int (*debugger_bpt)(struct pt_regs *regs) = xmon_bpt;
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int (*debugger_sstep)(struct pt_regs *regs) = xmon_sstep;
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int (*debugger_iabr_match)(struct pt_regs *regs) = xmon_iabr_match;
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int (*debugger_dabr_match)(struct pt_regs *regs) = xmon_dabr_match;
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void (*debugger_fault_handler)(struct pt_regs *regs);
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#else
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#ifdef CONFIG_KGDB
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void (*debugger)(struct pt_regs *regs);
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int (*debugger_bpt)(struct pt_regs *regs);
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int (*debugger_sstep)(struct pt_regs *regs);
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int (*debugger_iabr_match)(struct pt_regs *regs);
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int (*debugger_dabr_match)(struct pt_regs *regs);
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void (*debugger_fault_handler)(struct pt_regs *regs);
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#else
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#define debugger(regs) do { } while (0)
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#define debugger_bpt(regs) 0
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#define debugger_sstep(regs) 0
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#define debugger_iabr_match(regs) 0
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#define debugger_dabr_match(regs) 0
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#define debugger_fault_handler ((void (*)(struct pt_regs *))0)
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#endif
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#endif
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/*
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* Trap & Exception support
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*/
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DEFINE_SPINLOCK(die_lock);
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void die(const char * str, struct pt_regs * fp, long err)
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{
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static int die_counter;
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int nl = 0;
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console_verbose();
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spin_lock_irq(&die_lock);
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#ifdef CONFIG_PMAC_BACKLIGHT
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set_backlight_enable(1);
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set_backlight_level(BACKLIGHT_MAX);
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#endif
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printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
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#ifdef CONFIG_PREEMPT
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printk("PREEMPT ");
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nl = 1;
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#endif
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#ifdef CONFIG_SMP
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printk("SMP NR_CPUS=%d ", NR_CPUS);
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nl = 1;
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#endif
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if (nl)
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printk("\n");
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show_regs(fp);
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spin_unlock_irq(&die_lock);
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/* do_exit() should take care of panic'ing from an interrupt
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* context so we don't handle it here
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*/
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do_exit(err);
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}
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void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
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{
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siginfo_t info;
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if (!user_mode(regs)) {
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debugger(regs);
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die("Exception in kernel mode", regs, signr);
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}
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info.si_signo = signr;
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info.si_errno = 0;
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info.si_code = code;
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info.si_addr = (void __user *) addr;
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force_sig_info(signr, &info, current);
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}
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/*
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* I/O accesses can cause machine checks on powermacs.
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* Check if the NIP corresponds to the address of a sync
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* instruction for which there is an entry in the exception
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* table.
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* Note that the 601 only takes a machine check on TEA
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* (transfer error ack) signal assertion, and does not
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* set any of the top 16 bits of SRR1.
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* -- paulus.
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*/
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static inline int check_io_access(struct pt_regs *regs)
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{
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#ifdef CONFIG_PPC_PMAC
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unsigned long msr = regs->msr;
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const struct exception_table_entry *entry;
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unsigned int *nip = (unsigned int *)regs->nip;
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if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000)))
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&& (entry = search_exception_tables(regs->nip)) != NULL) {
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/*
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* Check that it's a sync instruction, or somewhere
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* in the twi; isync; nop sequence that inb/inw/inl uses.
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* As the address is in the exception table
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* we should be able to read the instr there.
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* For the debug message, we look at the preceding
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* load or store.
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*/
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if (*nip == 0x60000000) /* nop */
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nip -= 2;
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else if (*nip == 0x4c00012c) /* isync */
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--nip;
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if (*nip == 0x7c0004ac || (*nip >> 26) == 3) {
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/* sync or twi */
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unsigned int rb;
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--nip;
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rb = (*nip >> 11) & 0x1f;
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printk(KERN_DEBUG "%s bad port %lx at %p\n",
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(*nip & 0x100)? "OUT to": "IN from",
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regs->gpr[rb] - _IO_BASE, nip);
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regs->msr |= MSR_RI;
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regs->nip = entry->fixup;
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return 1;
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}
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}
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#endif /* CONFIG_PPC_PMAC */
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return 0;
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}
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#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
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/* On 4xx, the reason for the machine check or program exception
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is in the ESR. */
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#define get_reason(regs) ((regs)->dsisr)
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#ifndef CONFIG_E500
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#define get_mc_reason(regs) ((regs)->dsisr)
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#else
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#define get_mc_reason(regs) (mfspr(SPRN_MCSR))
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#endif
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#define REASON_FP ESR_FP
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#define REASON_ILLEGAL ESR_PIL
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#define REASON_PRIVILEGED ESR_PPR
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#define REASON_TRAP ESR_PTR
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/* single-step stuff */
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#define single_stepping(regs) (current->thread.dbcr0 & DBCR0_IC)
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#define clear_single_step(regs) (current->thread.dbcr0 &= ~DBCR0_IC)
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#else
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/* On non-4xx, the reason for the machine check or program
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exception is in the MSR. */
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#define get_reason(regs) ((regs)->msr)
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#define get_mc_reason(regs) ((regs)->msr)
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#define REASON_FP 0x100000
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#define REASON_ILLEGAL 0x80000
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#define REASON_PRIVILEGED 0x40000
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#define REASON_TRAP 0x20000
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#define single_stepping(regs) ((regs)->msr & MSR_SE)
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#define clear_single_step(regs) ((regs)->msr &= ~MSR_SE)
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#endif
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/*
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* This is "fall-back" implementation for configurations
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* which don't provide platform-specific machine check info
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*/
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void __attribute__ ((weak))
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platform_machine_check(struct pt_regs *regs)
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{
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}
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void MachineCheckException(struct pt_regs *regs)
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{
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unsigned long reason = get_mc_reason(regs);
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if (user_mode(regs)) {
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regs->msr |= MSR_RI;
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_exception(SIGBUS, regs, BUS_ADRERR, regs->nip);
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return;
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}
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#if defined(CONFIG_8xx) && defined(CONFIG_PCI)
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/* the qspan pci read routines can cause machine checks -- Cort */
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bad_page_fault(regs, regs->dar, SIGBUS);
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return;
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#endif
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if (debugger_fault_handler) {
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debugger_fault_handler(regs);
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regs->msr |= MSR_RI;
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return;
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}
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if (check_io_access(regs))
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return;
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#if defined(CONFIG_4xx) && !defined(CONFIG_440A)
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if (reason & ESR_IMCP) {
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printk("Instruction");
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mtspr(SPRN_ESR, reason & ~ESR_IMCP);
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} else
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printk("Data");
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printk(" machine check in kernel mode.\n");
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#elif defined(CONFIG_440A)
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printk("Machine check in kernel mode.\n");
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if (reason & ESR_IMCP){
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printk("Instruction Synchronous Machine Check exception\n");
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mtspr(SPRN_ESR, reason & ~ESR_IMCP);
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}
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else {
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u32 mcsr = mfspr(SPRN_MCSR);
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if (mcsr & MCSR_IB)
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printk("Instruction Read PLB Error\n");
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if (mcsr & MCSR_DRB)
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printk("Data Read PLB Error\n");
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if (mcsr & MCSR_DWB)
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printk("Data Write PLB Error\n");
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if (mcsr & MCSR_TLBP)
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printk("TLB Parity Error\n");
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if (mcsr & MCSR_ICP){
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flush_instruction_cache();
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printk("I-Cache Parity Error\n");
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}
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if (mcsr & MCSR_DCSP)
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printk("D-Cache Search Parity Error\n");
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if (mcsr & MCSR_DCFP)
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printk("D-Cache Flush Parity Error\n");
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if (mcsr & MCSR_IMPE)
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printk("Machine Check exception is imprecise\n");
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/* Clear MCSR */
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mtspr(SPRN_MCSR, mcsr);
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}
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#elif defined (CONFIG_E500)
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printk("Machine check in kernel mode.\n");
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printk("Caused by (from MCSR=%lx): ", reason);
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if (reason & MCSR_MCP)
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printk("Machine Check Signal\n");
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if (reason & MCSR_ICPERR)
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printk("Instruction Cache Parity Error\n");
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if (reason & MCSR_DCP_PERR)
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printk("Data Cache Push Parity Error\n");
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if (reason & MCSR_DCPERR)
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printk("Data Cache Parity Error\n");
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if (reason & MCSR_GL_CI)
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printk("Guarded Load or Cache-Inhibited stwcx.\n");
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if (reason & MCSR_BUS_IAERR)
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printk("Bus - Instruction Address Error\n");
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if (reason & MCSR_BUS_RAERR)
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printk("Bus - Read Address Error\n");
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if (reason & MCSR_BUS_WAERR)
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printk("Bus - Write Address Error\n");
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if (reason & MCSR_BUS_IBERR)
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printk("Bus - Instruction Data Error\n");
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if (reason & MCSR_BUS_RBERR)
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printk("Bus - Read Data Bus Error\n");
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if (reason & MCSR_BUS_WBERR)
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printk("Bus - Read Data Bus Error\n");
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if (reason & MCSR_BUS_IPERR)
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printk("Bus - Instruction Parity Error\n");
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if (reason & MCSR_BUS_RPERR)
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printk("Bus - Read Parity Error\n");
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#else /* !CONFIG_4xx && !CONFIG_E500 */
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printk("Machine check in kernel mode.\n");
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printk("Caused by (from SRR1=%lx): ", reason);
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switch (reason & 0x601F0000) {
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case 0x80000:
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printk("Machine check signal\n");
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break;
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case 0: /* for 601 */
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case 0x40000:
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case 0x140000: /* 7450 MSS error and TEA */
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printk("Transfer error ack signal\n");
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break;
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case 0x20000:
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printk("Data parity error signal\n");
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break;
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case 0x10000:
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printk("Address parity error signal\n");
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break;
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case 0x20000000:
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printk("L1 Data Cache error\n");
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break;
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case 0x40000000:
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printk("L1 Instruction Cache error\n");
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break;
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case 0x00100000:
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printk("L2 data cache parity error\n");
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break;
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default:
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printk("Unknown values in msr\n");
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}
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#endif /* CONFIG_4xx */
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/*
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* Optional platform-provided routine to print out
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* additional info, e.g. bus error registers.
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*/
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platform_machine_check(regs);
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debugger(regs);
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die("machine check", regs, SIGBUS);
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}
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void SMIException(struct pt_regs *regs)
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{
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debugger(regs);
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#if !(defined(CONFIG_XMON) || defined(CONFIG_KGDB))
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show_regs(regs);
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panic("System Management Interrupt");
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#endif
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}
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void UnknownException(struct pt_regs *regs)
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{
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printk("Bad trap at PC: %lx, MSR: %lx, vector=%lx %s\n",
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regs->nip, regs->msr, regs->trap, print_tainted());
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_exception(SIGTRAP, regs, 0, 0);
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}
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void InstructionBreakpoint(struct pt_regs *regs)
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{
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if (debugger_iabr_match(regs))
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return;
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_exception(SIGTRAP, regs, TRAP_BRKPT, 0);
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}
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void RunModeException(struct pt_regs *regs)
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{
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_exception(SIGTRAP, regs, 0, 0);
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}
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/* Illegal instruction emulation support. Originally written to
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* provide the PVR to user applications using the mfspr rd, PVR.
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* Return non-zero if we can't emulate, or -EFAULT if the associated
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* memory access caused an access fault. Return zero on success.
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*
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* There are a couple of ways to do this, either "decode" the instruction
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* or directly match lots of bits. In this case, matching lots of
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* bits is faster and easier.
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*
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*/
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#define INST_MFSPR_PVR 0x7c1f42a6
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#define INST_MFSPR_PVR_MASK 0xfc1fffff
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#define INST_DCBA 0x7c0005ec
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#define INST_DCBA_MASK 0x7c0007fe
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#define INST_MCRXR 0x7c000400
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#define INST_MCRXR_MASK 0x7c0007fe
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#define INST_STRING 0x7c00042a
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#define INST_STRING_MASK 0x7c0007fe
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#define INST_STRING_GEN_MASK 0x7c00067e
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#define INST_LSWI 0x7c0004aa
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#define INST_LSWX 0x7c00042a
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#define INST_STSWI 0x7c0005aa
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#define INST_STSWX 0x7c00052a
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static int emulate_string_inst(struct pt_regs *regs, u32 instword)
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{
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u8 rT = (instword >> 21) & 0x1f;
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u8 rA = (instword >> 16) & 0x1f;
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u8 NB_RB = (instword >> 11) & 0x1f;
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u32 num_bytes;
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unsigned long EA;
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int pos = 0;
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/* Early out if we are an invalid form of lswx */
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if ((instword & INST_STRING_MASK) == INST_LSWX)
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if ((rT == rA) || (rT == NB_RB))
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return -EINVAL;
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EA = (rA == 0) ? 0 : regs->gpr[rA];
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switch (instword & INST_STRING_MASK) {
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case INST_LSWX:
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case INST_STSWX:
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EA += NB_RB;
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num_bytes = regs->xer & 0x7f;
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break;
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case INST_LSWI:
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case INST_STSWI:
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num_bytes = (NB_RB == 0) ? 32 : NB_RB;
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break;
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default:
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return -EINVAL;
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}
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|
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while (num_bytes != 0)
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{
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u8 val;
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u32 shift = 8 * (3 - (pos & 0x3));
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switch ((instword & INST_STRING_MASK)) {
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case INST_LSWX:
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case INST_LSWI:
|
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if (get_user(val, (u8 __user *)EA))
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return -EFAULT;
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/* first time updating this reg,
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* zero it out */
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if (pos == 0)
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regs->gpr[rT] = 0;
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regs->gpr[rT] |= val << shift;
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break;
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case INST_STSWI:
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case INST_STSWX:
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val = regs->gpr[rT] >> shift;
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if (put_user(val, (u8 __user *)EA))
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return -EFAULT;
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break;
|
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}
|
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/* move EA to next address */
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EA += 1;
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num_bytes--;
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|
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/* manage our position within the register */
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if (++pos == 4) {
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pos = 0;
|
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if (++rT == 32)
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rT = 0;
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}
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}
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|
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return 0;
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}
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|
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static int emulate_instruction(struct pt_regs *regs)
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{
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u32 instword;
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u32 rd;
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|
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if (!user_mode(regs))
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return -EINVAL;
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CHECK_FULL_REGS(regs);
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|
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if (get_user(instword, (u32 __user *)(regs->nip)))
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return -EFAULT;
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|
|
/* Emulate the mfspr rD, PVR.
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*/
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if ((instword & INST_MFSPR_PVR_MASK) == INST_MFSPR_PVR) {
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rd = (instword >> 21) & 0x1f;
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regs->gpr[rd] = mfspr(SPRN_PVR);
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return 0;
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}
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|
|
/* 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;
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
|
|
static 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);
|
|
}
|
|
|
|
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 ProgramCheckException(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 */
|
|
int code = 0;
|
|
u32 fpscr;
|
|
|
|
/* We must make sure the FP state is consistent with
|
|
* our MSR_FP in regs
|
|
*/
|
|
preempt_disable();
|
|
if (regs->msr & MSR_FP)
|
|
giveup_fpu(current);
|
|
preempt_enable();
|
|
|
|
fpscr = current->thread.fpscr;
|
|
fpscr &= fpscr << 22; /* mask summary bits with enables */
|
|
if (fpscr & FPSCR_VX)
|
|
code = FPE_FLTINV;
|
|
else if (fpscr & FPSCR_OX)
|
|
code = FPE_FLTOVF;
|
|
else if (fpscr & FPSCR_UX)
|
|
code = FPE_FLTUND;
|
|
else if (fpscr & FPSCR_ZX)
|
|
code = FPE_FLTDIV;
|
|
else if (fpscr & FPSCR_XX)
|
|
code = FPE_FLTRES;
|
|
_exception(SIGFPE, regs, code, regs->nip);
|
|
return;
|
|
}
|
|
|
|
if (reason & REASON_TRAP) {
|
|
/* trap exception */
|
|
if (debugger_bpt(regs))
|
|
return;
|
|
if (check_bug_trap(regs)) {
|
|
regs->nip += 4;
|
|
return;
|
|
}
|
|
_exception(SIGTRAP, regs, TRAP_BRKPT, 0);
|
|
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 SingleStepException(struct pt_regs *regs)
|
|
{
|
|
regs->msr &= ~(MSR_SE | MSR_BE); /* Turn off 'trace' bits */
|
|
if (debugger_sstep(regs))
|
|
return;
|
|
_exception(SIGTRAP, regs, TRAP_TRACE, 0);
|
|
}
|
|
|
|
void AlignmentException(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;
|
|
}
|
|
if (fixed == -EFAULT) {
|
|
/* fixed == -EFAULT means the operand address was bad */
|
|
if (user_mode(regs))
|
|
_exception(SIGSEGV, regs, SEGV_ACCERR, regs->dar);
|
|
else
|
|
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());
|
|
}
|
|
|
|
#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 */
|
|
|
|
void AltivecUnavailException(struct pt_regs *regs)
|
|
{
|
|
static int kernel_altivec_count;
|
|
|
|
#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
|
|
/* The kernel has executed an altivec instruction without
|
|
first enabling altivec. Whinge but let it do it. */
|
|
if (++kernel_altivec_count < 10)
|
|
printk(KERN_ERR "AltiVec used in kernel (task=%p, pc=%lx)\n",
|
|
current, regs->nip);
|
|
regs->msr |= MSR_VEC;
|
|
}
|
|
|
|
#ifdef CONFIG_ALTIVEC
|
|
void AltivecAssistException(struct pt_regs *regs)
|
|
{
|
|
int err;
|
|
|
|
preempt_disable();
|
|
if (regs->msr & MSR_VEC)
|
|
giveup_altivec(current);
|
|
preempt_enable();
|
|
if (!user_mode(regs)) {
|
|
printk(KERN_ERR "altivec assist exception in kernel mode"
|
|
" at %lx\n", regs->nip);
|
|
debugger(regs);
|
|
die("altivec assist exception", regs, SIGFPE);
|
|
return;
|
|
}
|
|
|
|
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(KERN_ERR "unrecognized altivec instruction "
|
|
"in %s at %lx\n", current->comm, regs->nip);
|
|
current->thread.vscr.u[3] |= 0x10000;
|
|
}
|
|
}
|
|
#endif /* CONFIG_ALTIVEC */
|
|
|
|
void PerformanceMonitorException(struct pt_regs *regs)
|
|
{
|
|
perf_irq(regs);
|
|
}
|
|
|
|
#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
|
|
|
|
void __init trap_init(void)
|
|
{
|
|
}
|