From: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>
Access to sta->ht_cap is protected by RCU. However,
hif_set_association_mode() may sleep, so it can't be called in RCU.
This patch fix this behavior by handling sta and its RCU directly from
function hif_set_association_mode().
Signed-off-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>
Fixes: d00149011066 ("staging: wfx: fix RCU usage")
---
drivers/staging/wfx/hif_tx_mib.h | 15 ++++++++++-----
drivers/staging/wfx/sta.c | 4 ++--
2 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/staging/wfx/hif_tx_mib.h b/drivers/staging/wfx/hif_tx_mib.h
index bf3769c2a9b6..26b1406f9f6c 100644
--- a/drivers/staging/wfx/hif_tx_mib.h
+++ b/drivers/staging/wfx/hif_tx_mib.h
@@ -191,10 +191,10 @@ static inline int hif_set_block_ack_policy(struct wfx_vif *wvif,
}
static inline int hif_set_association_mode(struct wfx_vif *wvif,
- struct ieee80211_bss_conf *info,
- struct ieee80211_sta_ht_cap *ht_cap)
+ struct ieee80211_bss_conf *info)
{
int basic_rates = wfx_rate_mask_to_hw(wvif->wdev, info->basic_rates);
+ struct ieee80211_sta *sta = NULL;
struct hif_mib_set_association_mode val = {
.preambtype_use = 1,
.mode = 1,
@@ -204,12 +204,17 @@ static inline int hif_set_association_mode(struct wfx_vif *wvif,
.basic_rate_set = cpu_to_le32(basic_rates)
};
+ rcu_read_lock(); // protect sta
+ if (info->bssid && !info->ibss_joined)
+ sta = ieee80211_find_sta(wvif->vif, info->bssid);
+
// FIXME: it is strange to not retrieve all information from bss_info
- if (ht_cap && ht_cap->ht_supported) {
- val.mpdu_start_spacing = ht_cap->ampdu_density;
+ if (sta && sta->ht_cap.ht_supported) {
+ val.mpdu_start_spacing = sta->ht_cap.ampdu_density;
if (!(info->ht_operation_mode & IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT))
- val.greenfield = !!(ht_cap->cap & IEEE80211_HT_CAP_GRN_FLD);
+ val.greenfield = !!(sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD);
}
+ rcu_read_unlock();
return hif_write_mib(wvif->wdev, wvif->id,
HIF_MIB_ID_SET_ASSOCIATION_MODE, &val, sizeof(val));
diff --git a/drivers/staging/wfx/sta.c b/drivers/staging/wfx/sta.c
index 010e13bcd33e..ed16475c207c 100644
--- a/drivers/staging/wfx/sta.c
+++ b/drivers/staging/wfx/sta.c
@@ -691,6 +691,7 @@ static void wfx_join_finalize(struct wfx_vif *wvif,
wfx_rate_mask_to_hw(wvif->wdev, sta->supp_rates[wvif->channel->band]);
else
wvif->bss_params.operational_rate_set = -1;
+ rcu_read_unlock();
if (sta &&
info->ht_operation_mode & IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT)
hif_dual_cts_protection(wvif, true);
@@ -703,8 +704,7 @@ static void wfx_join_finalize(struct wfx_vif *wvif,
wvif->bss_params.beacon_lost_count = 20;
wvif->bss_params.aid = info->aid;
- hif_set_association_mode(wvif, info, sta ? &sta->ht_cap : NULL);
- rcu_read_unlock();
+ hif_set_association_mode(wvif, info);
if (!info->ibss_joined) {
hif_keep_alive_period(wvif, 30 /* sec */);
--
2.25.1
