kernel/debug: Mask KGDB NMI upon entry
The new arch callback should manage NMIs that usually cause KGDB to
enter. That is, not all NMIs should be enabled/disabled, but only
those that issue kgdb_handle_exception().
We must mask it as serial-line interrupt can be used as an NMI, so
if the original KGDB-entry cause was say a breakpoint, then every
input to KDB console will cause KGDB to reenter, which we don't want.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index c4d2fc1..7800cce 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -240,6 +240,7 @@
* hardware breakpoints.
* @correct_hw_break: Allow an architecture to specify how to correct the
* hardware debug registers.
+ * @enable_nmi: Manage NMI-triggered entry to KGDB
*/
struct kgdb_arch {
unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE];
@@ -252,6 +253,8 @@
void (*disable_hw_break)(struct pt_regs *regs);
void (*remove_all_hw_break)(void);
void (*correct_hw_break)(void);
+
+ void (*enable_nmi)(bool on);
};
/**