common/kmdb/kmdb_fault.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * Handling of unintentional faults (i.e. bugs) in the debugger.
 */

#include <stdlib.h>

#include <kmdb/kmdb_fault.h>
#include <kmdb/kmdb_promif.h>
#include <kmdb/kmdb_kdi.h>
#include <kmdb/kmdb_dpi.h>
#include <mdb/mdb_debug.h>
#include <mdb/mdb_kreg.h>
#include <mdb/mdb_io_impl.h>
#include <mdb/mdb.h>

void
kmdb_fault(kreg_t tt, kreg_t pc, kreg_t sp, int cpuid)
{
    int debug_self_confirm = 0, try;
    jmp_buf pcb, *old;
    char c;

    /* Make absolutely sure */
    kmdb_kdi_system_claim();

    try = 1;
    if (setjmp(pcb) != 0) {
        if (++try == 2) {
            mdb_iob_printf(mdb.m_err,
                "\n*** First stack trace attempt failed.  "
                "Trying safe mode.\n\n");

            kmdb_fault_display(tt, pc, sp, 1);
        } else {
            mdb_iob_printf(mdb.m_err,
                "\n*** Unable to print stack trace.\n");
        }

    } else {
        old = kmdb_dpi_set_fault_hdlr(&pcb);

        mdb_iob_printf(mdb.m_err, "\n*** Debugger Fault (CPU %d)\n\n",
            cpuid);
        kmdb_fault_display(tt, pc, sp, 0);
    }

    kmdb_dpi_restore_fault_hdlr(old);

    if (mdb.m_term != NULL) {
        for (;;) {
            mdb_iob_printf(mdb.m_err, "\n%s: "
#if defined(__sparc)
#ifndef sun4v
                "(o)bp, "
#endif /* sun4v */
                "(p)anic"
#else
                "reboo(t)"
#endif
                ", or (d)ebug with self? ", mdb.m_pname);
            mdb_iob_flush(mdb.m_err);

            if (IOP_READ(mdb.m_term, &c, sizeof (c)) != sizeof (c))
                goto fault_obp;

            mdb_iob_printf(mdb.m_err, "\n");

            switch (c) {
#ifdef __sparc
            case 'p':
                kmdb_dpi_kernpanic(cpuid);
                /*NOTREACHED*/
                continue;
#endif

#ifndef sun4v
            case 'o':
            case 'O':
#endif /* sun4v */
            case 't':
            case 'T':
                kmdb_dpi_enter_mon();
                continue;

            case 'd':
            case 'D':
                /*
                 * Debug self - get confirmation, because they
                 * can't go back to their running system if
                 * they choose this one.
                 */
                if (debug_self_confirm == 0) {
                    mdb_iob_printf(mdb.m_err,
                        "NOTE: You will not be able to "
                        "resume your system if you "
                        "choose this option.\nPlease "
                        "select 'd' again to confirm.\n");
                    debug_self_confirm = 1;
                    continue;
                }

                kmdb_dpi_set_state(DPI_STATE_LOST, 0);
                return;
            }
        }
    }

fault_obp:
    exit(1);
    /*NOTREACHED*/
}