mmc: Drain the intrhook in mmc_detach()

Buggy SD card drivers may attach and detach a mmc(4) driver instance in
quick succession.  In this case mmc(4) must disestablish its intrhook
callback during detach.  Thus, this change adds a call to
config_intrhook_drain(), which blocks or does nothing if the intrhook is
running or has already ran (the SD card was plugged in), and
disestablishes the hook if it hasn't ran yet (the SD card was not
plugged in).

PR:		254373
Reviewed by:	imp, manu, markj
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D31262

This commit is contained in:

Yang Zhong

2021-07-22 13:16:01 -04:00

committed by

Mark Johnston

parent fd5827b178

commit d5341d72a1

1 changed files with 1 additions and 0 deletions

									
										sys/dev/mmc/mmc.c
									
		+1
		
												View File
												
				@@ -271,6 +271,7 @@ mmc_detach(device_t dev)

					struct mmc_softc *sc = device_get_softc(dev);

					int err;

					config_intrhook_drain(&sc->config_intrhook);

					err = mmc_delete_cards(sc, true);

					if (err != 0)

						return (err);