diff options
| author | Martin Blumenstingl <martin.blumenstingl@googlemail.com> | 2023-01-08 22:13:22 +0100 |
|---|---|---|
| committer | Kalle Valo <kvalo@kernel.org> | 2023-01-16 18:27:43 +0200 |
| commit | 8a1e2fd8e2da5c8b8c438e20ebffef6881cc9ab8 (patch) | |
| tree | d83af21810a313da7b06236a3d6794a7fdf39397 | |
| parent | 2a86aa9a1892d60ef2e3f310f5b42b8b05546d65 (diff) | |
wifi: rtw88: Move register access from rtw_bf_assoc() outside the RCU
USB and (upcoming) SDIO support may sleep in the read/write handlers.
Shrink the RCU critical section so it only cover the call to
ieee80211_find_sta() and finding the ic_vht_cap/vht_cap based on the
found station. This moves the chip's BFEE configuration outside the
rcu_read_lock section and thus prevent "scheduling while atomic" or
"Voluntary context switch within RCU read-side critical section!"
warnings when accessing the registers using an SDIO card (which is
where this issue has been spotted in the real world - but it also
affects USB cards).
Reviewed-by: Ping-Ke Shih <pkshih@realtek.com>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230108211324.442823-2-martin.blumenstingl@googlemail.com
| -rw-r--r-- | drivers/net/wireless/realtek/rtw88/bf.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/net/wireless/realtek/rtw88/bf.c b/drivers/net/wireless/realtek/rtw88/bf.c index 038a30b170ef..c827c4a2814b 100644 --- a/drivers/net/wireless/realtek/rtw88/bf.c +++ b/drivers/net/wireless/realtek/rtw88/bf.c @@ -49,19 +49,23 @@ void rtw_bf_assoc(struct rtw_dev *rtwdev, struct ieee80211_vif *vif, sta = ieee80211_find_sta(vif, bssid); if (!sta) { + rcu_read_unlock(); + rtw_warn(rtwdev, "failed to find station entry for bss %pM\n", bssid); - goto out_unlock; + return; } ic_vht_cap = &hw->wiphy->bands[NL80211_BAND_5GHZ]->vht_cap; vht_cap = &sta->deflink.vht_cap; + rcu_read_unlock(); + if ((ic_vht_cap->cap & IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE) && (vht_cap->cap & IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE)) { if (bfinfo->bfer_mu_cnt >= chip->bfer_mu_max_num) { rtw_dbg(rtwdev, RTW_DBG_BF, "mu bfer number over limit\n"); - goto out_unlock; + return; } ether_addr_copy(bfee->mac_addr, bssid); @@ -75,7 +79,7 @@ void rtw_bf_assoc(struct rtw_dev *rtwdev, struct ieee80211_vif *vif, (vht_cap->cap & IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE)) { if (bfinfo->bfer_su_cnt >= chip->bfer_su_max_num) { rtw_dbg(rtwdev, RTW_DBG_BF, "su bfer number over limit\n"); - goto out_unlock; + return; } sound_dim = vht_cap->cap & @@ -98,9 +102,6 @@ void rtw_bf_assoc(struct rtw_dev *rtwdev, struct ieee80211_vif *vif, rtw_chip_config_bfee(rtwdev, rtwvif, bfee, true); } - -out_unlock: - rcu_read_unlock(); } void rtw_bf_init_bfer_entry_mu(struct rtw_dev *rtwdev, |