[PATCH RFC v1 5/7] rtw88: Configure the registers from rtw_bf_assoc() outside the RCU lock

Martin Blumenstingl
2021-07-17T20:42:00Z

Upcoming SDIO support may sleep in the read/write handlers. Configure
the chip's BFEE configuration set from rtw_bf_assoc() outside the
rcu_read_lock section to prevent a "scheduling while atomic" issue.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
drivers/net/wireless/realtek/rtw88/bf.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/bf.c b/drivers/net/wireless/realtek/rtw88/bf.c
index aff70e4ae028..06034d5d6f6c 100644
--- a/drivers/net/wireless/realtek/rtw88/bf.c
+++ b/drivers/net/wireless/realtek/rtw88/bf.c
@@ -39,6 +39,7 @@ void rtw_bf_assoc(struct rtw_dev *rtwdev, struct ieee80211_vif *vif,
struct ieee80211_sta_vht_cap *vht_cap;
struct ieee80211_sta_vht_cap *ic_vht_cap;
const u8 *bssid = bss_conf->bssid;
+ bool config_bfee = false;
u32 sound_dim;
u8 i;

@@ -70,7 +71,7 @@ void rtw_bf_assoc(struct rtw_dev *rtwdev, struct ieee80211_vif *vif,
bfee->aid = bss_conf->aid;
bfinfo->bfer_mu_cnt++;

- rtw_chip_config_bfee(rtwdev, rtwvif, bfee, true);
+ config_bfee = true;
} else if ((ic_vht_cap->cap & IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE) &&
(vht_cap->cap & IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE)) {
if (bfinfo->bfer_su_cnt >= chip->bfer_su_max_num) {
@@ -96,11 +97,14 @@ void rtw_bf_assoc(struct rtw_dev *rtwdev, struct ieee80211_vif *vif,
}
}

- rtw_chip_config_bfee(rtwdev, rtwvif, bfee, true);
+ config_bfee = true;
}

out_unlock:
rcu_read_unlock();
+
+ if (config_bfee)
+ rtw_chip_config_bfee(rtwdev, rtwvif, bfee, true);
}

void rtw_bf_init_bfer_entry_mu(struct rtw_dev *rtwdev,
--
2.32.0