path: root/kernel
diff options
authorJason Wessel <jason.wessel@windriver.com>2013-02-04 10:35:33 -0600
committerJason Wessel <jason.wessel@windriver.com>2013-03-02 08:52:19 -0600
commita37372f6c3c03dc7613eaae8bb3458c8068f5fff (patch)
treecf64786123ce7c2d47002d1d6b122967abca0eb5 /kernel
parent1b2caa2dcb8f18d2be9c5c3c992cb6da03f1a70a (diff)
kdb: Prevent kernel oops with kdb_defcmd
The kdb_defcmd can only be used to display the available command aliases while using the kernel debug shell. If you try to define a new macro while the kernel debugger is active it will oops. The debug shell macros must use pre-allocated memory set aside at the time kdb_init() is run, and the kdb_defcmd is restricted to only working at the time that the kdb_init sequence is being run, which only occurs if you actually activate the kernel debugger. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Diffstat (limited to 'kernel')
1 files changed, 6 insertions, 2 deletions
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index cdfc0a7e583..496f596aa80 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -681,6 +681,10 @@ static int kdb_defcmd(int argc, const char **argv)
if (argc != 3)
+ if (in_dbg_master()) {
+ kdb_printf("Command only available during kdb_init()\n");
+ return KDB_NOTIMP;
+ }
defcmd_set = kmalloc((defcmd_set_count + 1) * sizeof(*defcmd_set),
if (!defcmd_set)
@@ -2796,8 +2800,8 @@ static void __init kdb_inittab(void)
"Stack traceback", 1, KDB_REPEAT_NONE);
kdb_register_repeat("btp", kdb_bt, "<pid>",
"Display stack for process <pid>", 0, KDB_REPEAT_NONE);
- kdb_register_repeat("bta", kdb_bt, "[DRSTCZEUIMA]",
- "Display stack all processes", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("bta", kdb_bt, "[D|R|S|T|C|Z|E|U|I|M|A]",
+ "Backtrace all processes matching state flag", 0, KDB_REPEAT_NONE);
kdb_register_repeat("btc", kdb_bt, "",
"Backtrace current process on each cpu", 0, KDB_REPEAT_NONE);
kdb_register_repeat("btt", kdb_bt, "<vaddr>",