[PATCH 5/7] kgdboc: Add ekgdboc for early use of the kernel debugger

From: Jason Wessel
Date: Tue May 18 2010 - 21:43:45 EST


The ekgdboc= differs from kgdboc= in that you can begin debuggin as
soon as the exceptions are setup and the kgdb I/O driver is available,
instead of waiting until the tty subsystem is available.

CC: kgdb-bugreport@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Jason Wessel <jason.wessel@xxxxxxxxxxxxx>
---
Documentation/kernel-parameters.txt | 6 ++++++
drivers/serial/kgdboc.c | 19 +++++++++++++++++++
2 files changed, 25 insertions(+), 0 deletions(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 414347e..e618c75 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -709,6 +709,12 @@ and is between 256 and 4096 characters. It is defined in the file
The VGA output is eventually overwritten by the real
console.

+ ekgdboc= [X86,KGDB] Allow early kernel console debugging
+ ekgdboc=kbd
+
+ This is desgined to be used in conjunction with
+ the boot argument: earlyprintk=vga
+
eata= [HW,SCSI]

edd= [EDD]
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index b765ab4..a9a94ae 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -223,6 +223,25 @@ static struct kgdb_io kgdboc_io_ops = {
.post_exception = kgdboc_post_exp_handler,
};

+#ifdef CONFIG_KGDB_SERIAL_CONSOLE
+/* This is only available if kgdboc is a built in for early debugging */
+int __init kgdboc_early_init(char *opt)
+{
+ /* save the first character of the config string because the
+ * init routine can destroy it.
+ */
+ char save_ch;
+
+ kgdboc_option_setup(opt);
+ save_ch = config[0];
+ init_kgdboc();
+ config[0] = save_ch;
+ return 0;
+}
+
+early_param("ekgdboc", kgdboc_early_init);
+#endif /* CONFIG_KGDB_SERIAL_CONSOLE */
+
module_init(init_kgdboc);
module_exit(cleanup_kgdboc);
module_param_call(kgdboc, param_set_kgdboc_var, param_get_string, &kps, 0644);
--
1.6.3.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/