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| author | Jason Wessel <jason.wessel@windriver.com> | 2013-02-04 10:35:33 -0600 |
|---|---|---|
| committer | Jason Wessel <jason.wessel@windriver.com> | 2013-03-02 08:52:19 -0600 |
| commit | a37372f6c3c03dc7613eaae8bb3458c8068f5fff (patch) | |
| tree | cf64786123ce7c2d47002d1d6b122967abca0eb5 /kernel/debug | |
| parent | 1b2caa2dcb8f18d2be9c5c3c992cb6da03f1a70a (diff) | |
| download | lwn-a37372f6c3c03dc7613eaae8bb3458c8068f5fff.tar.gz lwn-a37372f6c3c03dc7613eaae8bb3458c8068f5fff.zip | |
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/debug')
| -rw-r--r-- | kernel/debug/kdb/kdb_main.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index cdfc0a7e583e..496f596aa807 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) return KDB_ARGCOUNT; + 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), GFP_KDB); 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>", |