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    Subject[patch 131/176] parisc : Remove broken line wrapping handling pdc_iodc_print()
    2.6.36-stable review patch.  If anyone has any objections, please let us know.

    ------------------

    From: Guy Martin <gmsoft@tuxicoman.be>

    commit fbea668498e93bb38ac9226c7af9120a25957375 upstream.

    Remove the broken line wrapping handling in pdc_iodc_print().
    It is broken in 3 ways :
    - It doesn't keep track of the current screen position, it just
    assumes that the new buffer will be printed at the begining of the
    screen.
    - It doesn't take in account that non printable characters won't
    increase the current position on the screen.
    - And last but not least, it triggers a kernel panic if a backspace
    is the first char in the provided buffer :

    Backtrace:
    [<0000000040128ec4>] pdc_console_write+0x44/0x78
    [<0000000040128f18>] pdc_console_tty_write+0x20/0x38
    [<000000004032f1ac>] n_tty_write+0x2a4/0x550
    [<000000004032b158>] tty_write+0x1e0/0x2d8
    [<00000000401bb420>] vfs_write+0xb8/0x188
    [<00000000401bb630>] sys_write+0x68/0xb8
    [<0000000040104eb8>] syscall_exit+0x0/0x14

    Most terminals handle the line wrapping just fine. I've confirmed that
    it works correctly on a C8000 with both vga and serial output.

    Signed-off-by: Guy Martin <gmsoft@tuxicoman.be>
    Signed-off-by: James Bottomley <James.Bottomley@suse.de>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    arch/parisc/kernel/firmware.c | 13 +------------
    1 file changed, 1 insertion(+), 12 deletions(-)

    --- a/arch/parisc/kernel/firmware.c
    +++ b/arch/parisc/kernel/firmware.c
    @@ -1126,15 +1126,13 @@ int pdc_iodc_print(const unsigned char *
    unsigned int i;
    unsigned long flags;

    - for (i = 0; i < count && i < 79;) {
    + for (i = 0; i < count;) {
    switch(str[i]) {
    case '\n':
    iodc_dbuf[i+0] = '\r';
    iodc_dbuf[i+1] = '\n';
    i += 2;
    goto print;
    - case '\b': /* BS */
    - i--; /* overwrite last */
    default:
    iodc_dbuf[i] = str[i];
    i++;
    @@ -1142,15 +1140,6 @@ int pdc_iodc_print(const unsigned char *
    }
    }

    - /* if we're at the end of line, and not already inserting a newline,
    - * insert one anyway. iodc console doesn't claim to support >79 char
    - * lines. don't account for this in the return value.
    - */
    - if (i == 79 && iodc_dbuf[i-1] != '\n') {
    - iodc_dbuf[i+0] = '\r';
    - iodc_dbuf[i+1] = '\n';
    - }
    -
    print:
    spin_lock_irqsave(&pdc_lock, flags);
    real32_call(PAGE0->mem_cons.iodc_io,



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