kdb_io.c

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/*
 * Kernel Debugger Architecture Independent Console I/O handler
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (c) 1999-2006 Silicon Graphics, Inc.  All Rights Reserved.
 * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/kdev_t.h>
#include <linux/console.h>
#include <linux/string.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/nmi.h>
#include <linux/delay.h>
#include <linux/kgdb.h>
#include <linux/kdb.h>
#include <linux/kallsyms.h>
#include "kdb_private.h"

#define CMD_BUFLEN 256
char kdb_prompt_str[CMD_BUFLEN];

int kdb_trap_printk;

static int kgdb_transition_check(char *buffer)
{
    if (buffer[0] != '+' && buffer[0] != '$') {
        KDB_STATE_SET(KGDB_TRANS);
        kdb_printf("%s", buffer);
    } else {
        int slen = strlen(buffer);
        if (slen > 3 && buffer[slen - 3] == '#') {
            kdb_gdb_state_pass(buffer);
            strcpy(buffer, "kgdb");
            KDB_STATE_SET(DOING_KGDB);
            return 1;
        }
    }
    return 0;
}

static int kdb_read_get_key(char *buffer, size_t bufsize)
{
#define ESCAPE_UDELAY 1000
#define ESCAPE_DELAY (2*1000000/ESCAPE_UDELAY) /* 2 seconds worth of udelays */
    char escape_data[5];    /* longest vt100 escape sequence is 4 bytes */
    char *ped = escape_data;
    int escape_delay = 0;
    get_char_func *f, *f_escape = NULL;
    int key;

    for (f = &kdb_poll_funcs[0]; ; ++f) {
        if (*f == NULL) {
            /* Reset NMI watchdog once per poll loop */
            touch_nmi_watchdog();
            f = &kdb_poll_funcs[0];
        }
        if (escape_delay == 2) {
            *ped = '\0';
            ped = escape_data;
            --escape_delay;
        }
        if (escape_delay == 1) {
            key = *ped++;
            if (!*ped)
                --escape_delay;
            break;
        }
        key = (*f)();
        if (key == -1) {
            if (escape_delay) {
                udelay(ESCAPE_UDELAY);
                --escape_delay;
            }
            continue;
        }
        if (bufsize <= 2) {
            if (key == '\r')
                key = '\n';
            *buffer++ = key;
            *buffer = '\0';
            return -1;
        }
        if (escape_delay == 0 && key == '\e') {
            escape_delay = ESCAPE_DELAY;
            ped = escape_data;
            f_escape = f;
        }
        if (escape_delay) {
            *ped++ = key;
            if (f_escape != f) {
                escape_delay = 2;
                continue;
            }
            if (ped - escape_data == 1) {
                /* \e */
                continue;
            } else if (ped - escape_data == 2) {
                /* \e<something> */
                if (key != '[')
                    escape_delay = 2;
                continue;
            } else if (ped - escape_data == 3) {
                /* \e[<something> */
                int mapkey = 0;
                switch (key) {
                case 'A': /* \e[A, up arrow */
                    mapkey = 16;
                    break;
                case 'B': /* \e[B, down arrow */
                    mapkey = 14;
                    break;
                case 'C': /* \e[C, right arrow */
                    mapkey = 6;
                    break;
                case 'D': /* \e[D, left arrow */
                    mapkey = 2;
                    break;
                case '1': /* dropthrough */
                case '3': /* dropthrough */
                /* \e[<1,3,4>], may be home, del, end */
                case '4':
                    mapkey = -1;
                    break;
                }
                if (mapkey != -1) {
                    if (mapkey > 0) {
                        escape_data[0] = mapkey;
                        escape_data[1] = '\0';
                    }
                    escape_delay = 2;
                }
                continue;
            } else if (ped - escape_data == 4) {
                /* \e[<1,3,4><something> */
                int mapkey = 0;
                if (key == '~') {
                    switch (escape_data[2]) {
                    case '1': /* \e[1~, home */
                        mapkey = 1;
                        break;
                    case '3': /* \e[3~, del */
                        mapkey = 4;
                        break;
                    case '4': /* \e[4~, end */
                        mapkey = 5;
                        break;
                    }
                }
                if (mapkey > 0) {
                    escape_data[0] = mapkey;
                    escape_data[1] = '\0';
                }
                escape_delay = 2;
                continue;
            }
        }
        break;  /* A key to process */
    }
    return key;
}

/*
 * kdb_read
 *
 *  This function reads a string of characters, terminated by
 *  a newline, or by reaching the end of the supplied buffer,
 *  from the current kernel debugger console device.
 * Parameters:
 *  buffer  - Address of character buffer to receive input characters.
 *  bufsize - size, in bytes, of the character buffer
 * Returns:
 *  Returns a pointer to the buffer containing the received
 *  character string.  This string will be terminated by a
 *  newline character.
 * Locking:
 *  No locks are required to be held upon entry to this
 *  function.  It is not reentrant - it relies on the fact
 *  that while kdb is running on only one "master debug" cpu.
 * Remarks:
 *
 * The buffer size must be >= 2.  A buffer size of 2 means that the caller only
 * wants a single key.
 *
 * An escape key could be the start of a vt100 control sequence such as \e[D
 * (left arrow) or it could be a character in its own right.  The standard
 * method for detecting the difference is to wait for 2 seconds to see if there
 * are any other characters.  kdb is complicated by the lack of a timer service
 * (interrupts are off), by multiple input sources and by the need to sometimes
 * return after just one key.  Escape sequence processing has to be done as
 * states in the polling loop.
 */

static char *kdb_read(char *buffer, size_t bufsize)
{
    char *cp = buffer;
    char *bufend = buffer+bufsize-2;    /* Reserve space for newline
                         * and null byte */
    char *lastchar;
    char *p_tmp;
    char tmp;
    static char tmpbuffer[CMD_BUFLEN];
    int len = strlen(buffer);
    int len_tmp;
    int tab = 0;
    int count;
    int i;
    int diag, dtab_count;
    int key;


    diag = kdbgetintenv("DTABCOUNT", &dtab_count);
    if (diag)
        dtab_count = 30;

    if (len > 0) {
        cp += len;
        if (*(buffer+len-1) == '\n')
            cp--;
    }

    lastchar = cp;
    *cp = '\0';
    kdb_printf("%s", buffer);
poll_again:
    key = kdb_read_get_key(buffer, bufsize);
    if (key == -1)
        return buffer;
    if (key != 9)
        tab = 0;
    switch (key) {
    case 8: /* backspace */
        if (cp > buffer) {
            if (cp < lastchar) {
                memcpy(tmpbuffer, cp, lastchar - cp);
                memcpy(cp-1, tmpbuffer, lastchar - cp);
            }
            *(--lastchar) = '\0';
            --cp;
            kdb_printf("\b%s \r", cp);
            tmp = *cp;
            *cp = '\0';
            kdb_printf(kdb_prompt_str);
            kdb_printf("%s", buffer);
            *cp = tmp;
        }
        break;
    case 13: /* enter */
        *lastchar++ = '\n';
        *lastchar++ = '\0';
        if (!KDB_STATE(KGDB_TRANS)) {
            KDB_STATE_SET(KGDB_TRANS);
            kdb_printf("%s", buffer);
        }
        kdb_printf("\n");
        return buffer;
    case 4: /* Del */
        if (cp < lastchar) {
            memcpy(tmpbuffer, cp+1, lastchar - cp - 1);
            memcpy(cp, tmpbuffer, lastchar - cp - 1);
            *(--lastchar) = '\0';
            kdb_printf("%s \r", cp);
            tmp = *cp;
            *cp = '\0';
            kdb_printf(kdb_prompt_str);
            kdb_printf("%s", buffer);
            *cp = tmp;
        }
        break;
    case 1: /* Home */
        if (cp > buffer) {
            kdb_printf("\r");
            kdb_printf(kdb_prompt_str);
            cp = buffer;
        }
        break;
    case 5: /* End */
        if (cp < lastchar) {
            kdb_printf("%s", cp);
            cp = lastchar;
        }
        break;
    case 2: /* Left */
        if (cp > buffer) {
            kdb_printf("\b");
            --cp;
        }
        break;
    case 14: /* Down */
        memset(tmpbuffer, ' ',
               strlen(kdb_prompt_str) + (lastchar-buffer));
        *(tmpbuffer+strlen(kdb_prompt_str) +
          (lastchar-buffer)) = '\0';
        kdb_printf("\r%s\r", tmpbuffer);
        *lastchar = (char)key;
        *(lastchar+1) = '\0';
        return lastchar;
    case 6: /* Right */
        if (cp < lastchar) {
            kdb_printf("%c", *cp);
            ++cp;
        }
        break;
    case 16: /* Up */
        memset(tmpbuffer, ' ',
               strlen(kdb_prompt_str) + (lastchar-buffer));
        *(tmpbuffer+strlen(kdb_prompt_str) +
          (lastchar-buffer)) = '\0';
        kdb_printf("\r%s\r", tmpbuffer);
        *lastchar = (char)key;
        *(lastchar+1) = '\0';
        return lastchar;
    case 9: /* Tab */
        if (tab < 2)
            ++tab;
        p_tmp = buffer;
        while (*p_tmp == ' ')
            p_tmp++;
        if (p_tmp > cp)
            break;
        memcpy(tmpbuffer, p_tmp, cp-p_tmp);
        *(tmpbuffer + (cp-p_tmp)) = '\0';
        p_tmp = strrchr(tmpbuffer, ' ');
        if (p_tmp)
            ++p_tmp;
        else
            p_tmp = tmpbuffer;
        len = strlen(p_tmp);
        count = kallsyms_symbol_complete(p_tmp,
                         sizeof(tmpbuffer) -
                         (p_tmp - tmpbuffer));
        if (tab == 2 && count > 0) {
            kdb_printf("\n%d symbols are found.", count);
            if (count > dtab_count) {
                count = dtab_count;
                kdb_printf(" But only first %d symbols will"
                       " be printed.\nYou can change the"
                       " environment variable DTABCOUNT.",
                       count);
            }
            kdb_printf("\n");
            for (i = 0; i < count; i++) {
                if (kallsyms_symbol_next(p_tmp, i) < 0)
                    break;
                kdb_printf("%s ", p_tmp);
                *(p_tmp + len) = '\0';
            }
            if (i >= dtab_count)
                kdb_printf("...");
            kdb_printf("\n");
            kdb_printf(kdb_prompt_str);
            kdb_printf("%s", buffer);
        } else if (tab != 2 && count > 0) {
            len_tmp = strlen(p_tmp);
            strncpy(p_tmp+len_tmp, cp, lastchar-cp+1);
            len_tmp = strlen(p_tmp);
            strncpy(cp, p_tmp+len, len_tmp-len + 1);
            len = len_tmp - len;
            kdb_printf("%s", cp);
            cp += len;
            lastchar += len;
        }
        kdb_nextline = 1; /* reset output line number */
        break;
    default:
        if (key >= 32 && lastchar < bufend) {
            if (cp < lastchar) {
                memcpy(tmpbuffer, cp, lastchar - cp);
                memcpy(cp+1, tmpbuffer, lastchar - cp);
                *++lastchar = '\0';
                *cp = key;
                kdb_printf("%s\r", cp);
                ++cp;
                tmp = *cp;
                *cp = '\0';
                kdb_printf(kdb_prompt_str);
                kdb_printf("%s", buffer);
                *cp = tmp;
            } else {
                *++lastchar = '\0';
                *cp++ = key;
                /* The kgdb transition check will hide
                 * printed characters if we think that
                 * kgdb is connecting, until the check
                 * fails */
                if (!KDB_STATE(KGDB_TRANS)) {
                    if (kgdb_transition_check(buffer))
                        return buffer;
                } else {
                    kdb_printf("%c", key);
                }
            }
            /* Special escape to kgdb */
            if (lastchar - buffer >= 5 &&
                strcmp(lastchar - 5, "$?#3f") == 0) {
                kdb_gdb_state_pass(lastchar - 5);
                strcpy(buffer, "kgdb");
                KDB_STATE_SET(DOING_KGDB);
                return buffer;
            }
            if (lastchar - buffer >= 11 &&
                strcmp(lastchar - 11, "$qSupported") == 0) {
                kdb_gdb_state_pass(lastchar - 11);
                strcpy(buffer, "kgdb");
                KDB_STATE_SET(DOING_KGDB);
                return buffer;
            }
        }
        break;
    }
    goto poll_again;
}

/*
 * kdb_getstr
 *
 *  Print the prompt string and read a command from the
 *  input device.
 *
 * Parameters:
 *  buffer  Address of buffer to receive command
 *  bufsize Size of buffer in bytes
 *  prompt  Pointer to string to use as prompt string
 * Returns:
 *  Pointer to command buffer.
 * Locking:
 *  None.
 * Remarks:
 *  For SMP kernels, the processor number will be
 *  substituted for %d, %x or %o in the prompt.
 */

char *kdb_getstr(char *buffer, size_t bufsize, char *prompt)
{
    if (prompt && kdb_prompt_str != prompt)
        strncpy(kdb_prompt_str, prompt, CMD_BUFLEN);
    kdb_printf(kdb_prompt_str);
    kdb_nextline = 1;   /* Prompt and input resets line number */
    return kdb_read(buffer, bufsize);
}

/*
 * kdb_input_flush
 *
 *  Get rid of any buffered console input.
 *
 * Parameters:
 *  none
 * Returns:
 *  nothing
 * Locking:
 *  none
 * Remarks:
 *  Call this function whenever you want to flush input.  If there is any
 *  outstanding input, it ignores all characters until there has been no
 *  data for approximately 1ms.
 */

static void kdb_input_flush(void)
{
    get_char_func *f;
    int res;
    int flush_delay = 1;
    while (flush_delay) {
        flush_delay--;
empty:
        touch_nmi_watchdog();
        for (f = &kdb_poll_funcs[0]; *f; ++f) {
            res = (*f)();
            if (res != -1) {
                flush_delay = 1;
                goto empty;
            }
        }
        if (flush_delay)
            mdelay(1);
    }
}

/*
 * kdb_printf
 *
 *  Print a string to the output device(s).
 *
 * Parameters:
 *  printf-like format and optional args.
 * Returns:
 *  0
 * Locking:
 *  None.
 * Remarks:
 *  use 'kdbcons->write()' to avoid polluting 'log_buf' with
 *  kdb output.
 *
 *  If the user is doing a cmd args | grep srch
 *  then kdb_grepping_flag is set.
 *  In that case we need to accumulate full lines (ending in \n) before
 *  searching for the pattern.
 */

static char kdb_buffer[256];    /* A bit too big to go on stack */
static char *next_avail = kdb_buffer;
static int  size_avail;
static int  suspend_grep;

/*
 * search arg1 to see if it contains arg2
 * (kdmain.c provides flags for ^pat and pat$)
 *
 * return 1 for found, 0 for not found
 */
static int kdb_search_string(char *searched, char *searchfor)
{
    char firstchar, *cp;
    int len1, len2;

    /* not counting the newline at the end of "searched" */
    len1 = strlen(searched)-1;
    len2 = strlen(searchfor);
    if (len1 < len2)
        return 0;
    if (kdb_grep_leading && kdb_grep_trailing && len1 != len2)
        return 0;
    if (kdb_grep_leading) {
        if (!strncmp(searched, searchfor, len2))
            return 1;
    } else if (kdb_grep_trailing) {
        if (!strncmp(searched+len1-len2, searchfor, len2))
            return 1;
    } else {
        firstchar = *searchfor;
        cp = searched;
        while ((cp = strchr(cp, firstchar))) {
            if (!strncmp(cp, searchfor, len2))
                return 1;
            cp++;
        }
    }
    return 0;
}

int vkdb_printf(const char *fmt, va_list ap)
{
    int diag;
    int linecount;
    int colcount;
    int logging, saved_loglevel = 0;
    int saved_trap_printk;
    int got_printf_lock = 0;
    int retlen = 0;
    int fnd, len;
    char *cp, *cp2, *cphold = NULL, replaced_byte = ' ';
    char *moreprompt = "more> ";
    struct console *c = console_drivers;
    static DEFINE_SPINLOCK(kdb_printf_lock);
    unsigned long uninitialized_var(flags);

    preempt_disable();
    saved_trap_printk = kdb_trap_printk;
    kdb_trap_printk = 0;

    /* Serialize kdb_printf if multiple cpus try to write at once.
     * But if any cpu goes recursive in kdb, just print the output,
     * even if it is interleaved with any other text.
     */
    if (!KDB_STATE(PRINTF_LOCK)) {
        KDB_STATE_SET(PRINTF_LOCK);
        spin_lock_irqsave(&kdb_printf_lock, flags);
        got_printf_lock = 1;
        atomic_inc(&kdb_event);
    } else {
        __acquire(kdb_printf_lock);
    }

    diag = kdbgetintenv("LINES", &linecount);
    if (diag || linecount <= 1)
        linecount = 24;

    diag = kdbgetintenv("COLUMNS", &colcount);
    if (diag || colcount <= 1)
        colcount = 80;

    diag = kdbgetintenv("LOGGING", &logging);
    if (diag)
        logging = 0;

    if (!kdb_grepping_flag || suspend_grep) {
        /* normally, every vsnprintf starts a new buffer */
        next_avail = kdb_buffer;
        size_avail = sizeof(kdb_buffer);
    }
    vsnprintf(next_avail, size_avail, fmt, ap);

    /*
     * If kdb_parse() found that the command was cmd xxx | grep yyy
     * then kdb_grepping_flag is set, and kdb_grep_string contains yyy
     *
     * Accumulate the print data up to a newline before searching it.
     * (vsnprintf does null-terminate the string that it generates)
     */

    /* skip the search if prints are temporarily unconditional */
    if (!suspend_grep && kdb_grepping_flag) {
        cp = strchr(kdb_buffer, '\n');
        if (!cp) {
            /*
             * Special cases that don't end with newlines
             * but should be written without one:
             *   The "[nn]kdb> " prompt should
             *   appear at the front of the buffer.
             *
             *   The "[nn]more " prompt should also be
             *     (MOREPROMPT -> moreprompt)
             *   written *   but we print that ourselves,
             *   we set the suspend_grep flag to make
             *   it unconditional.
             *
             */
            if (next_avail == kdb_buffer) {
                /*
                 * these should occur after a newline,
                 * so they will be at the front of the
                 * buffer
                 */
                cp2 = kdb_buffer;
                len = strlen(kdb_prompt_str);
                if (!strncmp(cp2, kdb_prompt_str, len)) {
                    /*
                     * We're about to start a new
                     * command, so we can go back
                     * to normal mode.
                     */
                    kdb_grepping_flag = 0;
                    goto kdb_printit;
                }
            }
            /* no newline; don't search/write the buffer
               until one is there */
            len = strlen(kdb_buffer);
            next_avail = kdb_buffer + len;
            size_avail = sizeof(kdb_buffer) - len;
            goto kdb_print_out;
        }

        /*
         * The newline is present; print through it or discard
         * it, depending on the results of the search.
         */
        cp++;            /* to byte after the newline */
        replaced_byte = *cp; /* remember what/where it was */
        cphold = cp;
        *cp = '\0';      /* end the string for our search */

        /*
         * We now have a newline at the end of the string
         * Only continue with this output if it contains the
         * search string.
         */
        fnd = kdb_search_string(kdb_buffer, kdb_grep_string);
        if (!fnd) {
            /*
             * At this point the complete line at the start
             * of kdb_buffer can be discarded, as it does
             * not contain what the user is looking for.
             * Shift the buffer left.
             */
            *cphold = replaced_byte;
            strcpy(kdb_buffer, cphold);
            len = strlen(kdb_buffer);
            next_avail = kdb_buffer + len;
            size_avail = sizeof(kdb_buffer) - len;
            goto kdb_print_out;
        }
        /*
         * at this point the string is a full line and
         * should be printed, up to the null.
         */
    }
kdb_printit:

    /*
     * Write to all consoles.
     */
    retlen = strlen(kdb_buffer);
    if (!dbg_kdb_mode && kgdb_connected) {
        gdbstub_msg_write(kdb_buffer, retlen);
    } else {
        if (dbg_io_ops && !dbg_io_ops->is_console) {
            len = retlen;
            cp = kdb_buffer;
            while (len--) {
                dbg_io_ops->write_char(*cp);
                cp++;
            }
        }
        while (c) {
            c->write(c, kdb_buffer, retlen);
            touch_nmi_watchdog();
            c = c->next;
        }
    }
    if (logging) {
        saved_loglevel = console_loglevel;
        console_loglevel = 0;
        printk(KERN_INFO "%s", kdb_buffer);
    }

    if (KDB_STATE(PAGER)) {
        /*
         * Check printed string to decide how to bump the
         * kdb_nextline to control when the more prompt should
         * show up.
         */
        int got = 0;
        len = retlen;
        while (len--) {
            if (kdb_buffer[len] == '\n') {
                kdb_nextline++;
                got = 0;
            } else if (kdb_buffer[len] == '\r') {
                got = 0;
            } else {
                got++;
            }
        }
        kdb_nextline += got / (colcount + 1);
    }

    /* check for having reached the LINES number of printed lines */
    if (kdb_nextline >= linecount) {
        char buf1[16] = "";

        /* Watch out for recursion here.  Any routine that calls
         * kdb_printf will come back through here.  And kdb_read
         * uses kdb_printf to echo on serial consoles ...
         */
        kdb_nextline = 1;   /* In case of recursion */

        /*
         * Pause until cr.
         */
        moreprompt = kdbgetenv("MOREPROMPT");
        if (moreprompt == NULL)
            moreprompt = "more> ";

        kdb_input_flush();
        c = console_drivers;

        if (dbg_io_ops && !dbg_io_ops->is_console) {
            len = strlen(moreprompt);
            cp = moreprompt;
            while (len--) {
                dbg_io_ops->write_char(*cp);
                cp++;
            }
        }
        while (c) {
            c->write(c, moreprompt, strlen(moreprompt));
            touch_nmi_watchdog();
            c = c->next;
        }

        if (logging)
            printk("%s", moreprompt);

        kdb_read(buf1, 2); /* '2' indicates to return
                    * immediately after getting one key. */
        kdb_nextline = 1;   /* Really set output line 1 */

        /* empty and reset the buffer: */
        kdb_buffer[0] = '\0';
        next_avail = kdb_buffer;
        size_avail = sizeof(kdb_buffer);
        if ((buf1[0] == 'q') || (buf1[0] == 'Q')) {
            /* user hit q or Q */
            KDB_FLAG_SET(CMD_INTERRUPT); /* command interrupted */
            KDB_STATE_CLEAR(PAGER);
            /* end of command output; back to normal mode */
            kdb_grepping_flag = 0;
            kdb_printf("\n");
        } else if (buf1[0] == ' ') {
            kdb_printf("\r");
            suspend_grep = 1; /* for this recursion */
        } else if (buf1[0] == '\n') {
            kdb_nextline = linecount - 1;
            kdb_printf("\r");
            suspend_grep = 1; /* for this recursion */
        } else if (buf1[0] && buf1[0] != '\n') {
            /* user hit something other than enter */
            suspend_grep = 1; /* for this recursion */
            kdb_printf("\nOnly 'q' or 'Q' are processed at more "
                   "prompt, input ignored\n");
        } else if (kdb_grepping_flag) {
            /* user hit enter */
            suspend_grep = 1; /* for this recursion */
            kdb_printf("\n");
        }
        kdb_input_flush();
    }

    /*
     * For grep searches, shift the printed string left.
     *  replaced_byte contains the character that was overwritten with
     *  the terminating null, and cphold points to the null.
     * Then adjust the notion of available space in the buffer.
     */
    if (kdb_grepping_flag && !suspend_grep) {
        *cphold = replaced_byte;
        strcpy(kdb_buffer, cphold);
        len = strlen(kdb_buffer);
        next_avail = kdb_buffer + len;
        size_avail = sizeof(kdb_buffer) - len;
    }

kdb_print_out:
    suspend_grep = 0; /* end of what may have been a recursive call */
    if (logging)
        console_loglevel = saved_loglevel;
    if (KDB_STATE(PRINTF_LOCK) && got_printf_lock) {
        got_printf_lock = 0;
        spin_unlock_irqrestore(&kdb_printf_lock, flags);
        KDB_STATE_CLEAR(PRINTF_LOCK);
        atomic_dec(&kdb_event);
    } else {
        __release(kdb_printf_lock);
    }
    kdb_trap_printk = saved_trap_printk;
    preempt_enable();
    return retlen;
}

int kdb_printf(const char *fmt, ...)
{
    va_list ap;
    int r;

    va_start(ap, fmt);
    r = vkdb_printf(fmt, ap);
    va_end(ap);

    return r;
}
EXPORT_SYMBOL_GPL(kdb_printf);