Index: ld_sdmmc.c
===================================================================
RCS file: /cvsroot/src/sys/dev/sdmmc/ld_sdmmc.c,v
retrieving revision 1.42
diff -p -u -r1.42 ld_sdmmc.c
--- ld_sdmmc.c	16 May 2022 10:03:23 -0000	1.42
+++ ld_sdmmc.c	22 Jan 2024 18:17:12 -0000
@@ -611,6 +611,8 @@ ld_sdmmc_cachesync(struct ld_softc *ld, 
 		goto out;
 	}
 
+	mutex_exit(&sc->sc_lock);
+
 	/* Set up the task and schedule it.  */
 	task->task_poll = poll;
 	task->task_errorp = &error;
@@ -618,6 +620,8 @@ ld_sdmmc_cachesync(struct ld_softc *ld, 
 
 	sdmmc_add_task(sc->sc_sf->sc, &task->task);
 
+	mutex_enter(&sc->sc_lock);
+
 	/*
 	 * Wait for the task to complete.  If the device is yanked,
 	 * detach will notify us.  Keep the busy count up until we're
@@ -626,7 +630,7 @@ ld_sdmmc_cachesync(struct ld_softc *ld, 
 	 */
 	sc->sc_busy++;
 	KASSERT(sc->sc_busy <= LD_SDMMC_MAXTASKCNT);
-	while (error == -1)
+	while (task->task.onqueue)
 		cv_wait(&sc->sc_cv, &sc->sc_lock);
 	if (--sc->sc_busy == 0)
 		cv_broadcast(&sc->sc_cv);
Index: sdmmc.c
===================================================================
RCS file: /cvsroot/src/sys/dev/sdmmc/sdmmc.c,v
retrieving revision 1.43
diff -p -u -r1.43 sdmmc.c
--- sdmmc.c	7 Aug 2021 16:19:16 -0000	1.43
+++ sdmmc.c	22 Jan 2024 18:17:12 -0000
@@ -265,6 +314,13 @@ sdmmc_add_task(struct sdmmc_softc *sc, s
 	}
 	KASSERT(task->sc == NULL);
 	KASSERT(!task->onqueue);
+
+	if (curlwp == sc->sc_tskq_lwp) {
+		mutex_exit(&sc->sc_tskq_mtx);
+		(*task->func)(task->arg);
+		return;
+	}
+
 	task->onqueue = 1;
 	task->sc = sc;
 	TAILQ_INSERT_TAIL(&sc->sc_tskq, task, next);