--- /tmp/orig/dev/crypto/tpm/tpm20.c	2026-07-23 11:54:56.704835000 +0000
+++ dev/crypto/tpm/tpm20.c	2026-07-23 11:57:17.676284000 +0000
@@ -212,6 +212,7 @@
 tpm20_release(struct tpm_sc *sc)
 {
 
+	callout_drain(&sc->discard_buffer_callout);
 #ifdef TPM_HARVEST
 	callout_drain(&sc->harvest_callout);
 #endif