From: Guy Martin Date: Mon, 6 Dec 2010 15:48:04 +0000 (+0100) Subject: parisc : Remove broken line wrapping handling pdc_iodc_print() X-Git-Tag: v2.6.37.1~73 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=49ae676572f86b2603bd3bd3f246a7c84ec25492;p=karo-tx-linux.git parisc : Remove broken line wrapping handling pdc_iodc_print() 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 Signed-off-by: James Bottomley Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/parisc/kernel/firmware.c b/arch/parisc/kernel/firmware.c index df971fa0c32f..4896ed090585 100644 --- a/arch/parisc/kernel/firmware.c +++ b/arch/parisc/kernel/firmware.c @@ -1126,15 +1126,13 @@ int pdc_iodc_print(const unsigned char *str, unsigned count) 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 *str, unsigned count) } } - /* 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,