Merging upstream version 4.19.269.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/firmware/google/gsmi.c b/drivers/firmware/google/gsmi.c
index 62337be07..2e3ef0eb6 100644
--- a/drivers/firmware/google/gsmi.c
+++ b/drivers/firmware/google/gsmi.c
@@ -661,6 +661,15 @@ static struct notifier_block gsmi_die_notifier = {
 static int gsmi_panic_callback(struct notifier_block *nb,
 			       unsigned long reason, void *arg)
 {
+
+	/*
+	 * Panic callbacks are executed with all other CPUs stopped,
+	 * so we must not attempt to spin waiting for gsmi_dev.lock
+	 * to be released.
+	 */
+	if (spin_is_locked(&gsmi_dev.lock))
+		return NOTIFY_DONE;
+
 	gsmi_shutdown_reason(GSMI_SHUTDOWN_PANIC);
 	return NOTIFY_DONE;
 }