[tip: irq/core] ath9k: Use tasklet_disable_in_atomic()

From: tip-bot2 for Sebastian Andrzej Siewior
Date: Wed Mar 17 2021 - 11:50:24 EST


The following commit has been merged into the irq/core branch of tip:

Commit-ID: 3250aa8a293b1859d76577714a3e1fe95732c721
Gitweb: https://git.kernel.org/tip/3250aa8a293b1859d76577714a3e1fe95732c721
Author: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
AuthorDate: Tue, 09 Mar 2021 09:42:13 +01:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Wed, 17 Mar 2021 16:34:02 +01:00

ath9k: Use tasklet_disable_in_atomic()

All callers of ath9k_beacon_ensure_primary_slot() are preemptible /
acquire a mutex except for this callchain:

spin_lock_bh(&sc->sc_pcu_lock);
ath_complete_reset()
-> ath9k_calculate_summary_state()
-> ath9k_beacon_ensure_primary_slot()

It's unclear how that can be distangled, so use tasklet_disable_in_atomic()
for now. This allows tasklet_disable() to become sleepable once the
remaining atomic users are cleaned up.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210309084242.313899703@xxxxxxxxxxxxx

---
drivers/net/wireless/ath/ath9k/beacon.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 71e2ada..72e2e71 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -251,7 +251,7 @@ void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc)
int first_slot = ATH_BCBUF;
int slot;

- tasklet_disable(&sc->bcon_tasklet);
+ tasklet_disable_in_atomic(&sc->bcon_tasklet);

/* Find first taken slot. */
for (slot = 0; slot < ATH_BCBUF; slot++) {