6.15-stable review patch. If anyone has any objections, please let me know.
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From: Lorenzo Bianconi lorenzo@kernel.org
[ Upstream commit 28d519d0d493a8cf3f8ca01f10d962c56cec1825 ]
Since mt7996_mcu_set_fixed_field() can't be executed in a RCU critical section, move RCU section in mt7996_mcu_add_rate_ctrl_fixed() and run mt7996_mcu_set_fixed_field() in non-atomic context. This is a preliminary patch to fix a 'sleep while atomic' issue in mt7996_mac_sta_rc_work().
Fixes: 0762bdd30279 ("wifi: mt76: mt7996: rework mt7996_mac_sta_rc_work to support MLO") Signed-off-by: Lorenzo Bianconi lorenzo@kernel.org Link: https://patch.msgid.link/20250605-mt7996-sleep-while-atomic-v1-3-d46d15f9203... Signed-off-by: Felix Fietkau nbd@nbd.name Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/wireless/mediatek/mt76/mt7996/mcu.c | 86 ++++++++++++------- 1 file changed, 57 insertions(+), 29 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c index d67ed58d7126d..6c2b258ce4ff6 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c +++ b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c @@ -1955,51 +1955,74 @@ int mt7996_mcu_set_fixed_field(struct mt7996_dev *dev, struct mt7996_sta *msta, }
static int -mt7996_mcu_add_rate_ctrl_fixed(struct mt7996_dev *dev, - struct ieee80211_link_sta *link_sta, - struct mt7996_vif_link *link, - struct mt7996_sta_link *msta_link, - u8 link_id) +mt7996_mcu_add_rate_ctrl_fixed(struct mt7996_dev *dev, struct mt7996_sta *msta, + struct ieee80211_vif *vif, u8 link_id) { - struct cfg80211_chan_def *chandef = &link->phy->mt76->chandef; - struct cfg80211_bitrate_mask *mask = &link->bitrate_mask; - enum nl80211_band band = chandef->chan->band; - struct mt7996_sta *msta = msta_link->sta; + struct ieee80211_link_sta *link_sta; + struct cfg80211_bitrate_mask mask; + struct mt7996_sta_link *msta_link; + struct mt7996_vif_link *link; struct sta_phy_uni phy = {}; - int ret, nrates = 0; + struct ieee80211_sta *sta; + int ret, nrates = 0, idx; + enum nl80211_band band; + bool has_he;
#define __sta_phy_bitrate_mask_check(_mcs, _gi, _ht, _he) \ do { \ - u8 i, gi = mask->control[band]._gi; \ + u8 i, gi = mask.control[band]._gi; \ gi = (_he) ? gi : gi == NL80211_TXRATE_FORCE_SGI; \ phy.sgi = gi; \ - phy.he_ltf = mask->control[band].he_ltf; \ - for (i = 0; i < ARRAY_SIZE(mask->control[band]._mcs); i++) { \ - if (!mask->control[band]._mcs[i]) \ + phy.he_ltf = mask.control[band].he_ltf; \ + for (i = 0; i < ARRAY_SIZE(mask.control[band]._mcs); i++) { \ + if (!mask.control[band]._mcs[i]) \ continue; \ - nrates += hweight16(mask->control[band]._mcs[i]); \ - phy.mcs = ffs(mask->control[band]._mcs[i]) - 1; \ + nrates += hweight16(mask.control[band]._mcs[i]); \ + phy.mcs = ffs(mask.control[band]._mcs[i]) - 1; \ if (_ht) \ phy.mcs += 8 * i; \ } \ } while (0)
- if (link_sta->he_cap.has_he) { + rcu_read_lock(); + + link = mt7996_vif_link(dev, vif, link_id); + if (!link) + goto error_unlock; + + msta_link = rcu_dereference(msta->link[link_id]); + if (!msta_link) + goto error_unlock; + + sta = wcid_to_sta(&msta_link->wcid); + link_sta = rcu_dereference(sta->link[link_id]); + if (!link_sta) + goto error_unlock; + + band = link->phy->mt76->chandef.chan->band; + has_he = link_sta->he_cap.has_he; + mask = link->bitrate_mask; + idx = msta_link->wcid.idx; + + if (has_he) { __sta_phy_bitrate_mask_check(he_mcs, he_gi, 0, 1); } else if (link_sta->vht_cap.vht_supported) { __sta_phy_bitrate_mask_check(vht_mcs, gi, 0, 0); } else if (link_sta->ht_cap.ht_supported) { __sta_phy_bitrate_mask_check(ht_mcs, gi, 1, 0); } else { - nrates = hweight32(mask->control[band].legacy); - phy.mcs = ffs(mask->control[band].legacy) - 1; + nrates = hweight32(mask.control[band].legacy); + phy.mcs = ffs(mask.control[band].legacy) - 1; } + + rcu_read_unlock(); + #undef __sta_phy_bitrate_mask_check
/* fall back to auto rate control */ - if (mask->control[band].gi == NL80211_TXRATE_DEFAULT_GI && - mask->control[band].he_gi == GENMASK(7, 0) && - mask->control[band].he_ltf == GENMASK(7, 0) && + if (mask.control[band].gi == NL80211_TXRATE_DEFAULT_GI && + mask.control[band].he_gi == GENMASK(7, 0) && + mask.control[band].he_ltf == GENMASK(7, 0) && nrates != 1) return 0;
@@ -2012,16 +2035,16 @@ mt7996_mcu_add_rate_ctrl_fixed(struct mt7996_dev *dev, }
/* fixed GI */ - if (mask->control[band].gi != NL80211_TXRATE_DEFAULT_GI || - mask->control[band].he_gi != GENMASK(7, 0)) { + if (mask.control[band].gi != NL80211_TXRATE_DEFAULT_GI || + mask.control[band].he_gi != GENMASK(7, 0)) { u32 addr;
/* firmware updates only TXCMD but doesn't take WTBL into * account, so driver should update here to reflect the * actual txrate hardware sends out. */ - addr = mt7996_mac_wtbl_lmac_addr(dev, msta_link->wcid.idx, 7); - if (link_sta->he_cap.has_he) + addr = mt7996_mac_wtbl_lmac_addr(dev, idx, 7); + if (has_he) mt76_rmw_field(dev, addr, GENMASK(31, 24), phy.sgi); else mt76_rmw_field(dev, addr, GENMASK(15, 12), phy.sgi); @@ -2033,7 +2056,7 @@ mt7996_mcu_add_rate_ctrl_fixed(struct mt7996_dev *dev, }
/* fixed HE_LTF */ - if (mask->control[band].he_ltf != GENMASK(7, 0)) { + if (mask.control[band].he_ltf != GENMASK(7, 0)) { ret = mt7996_mcu_set_fixed_field(dev, msta, &phy, link_id, RATE_PARAM_FIXED_HE_LTF); if (ret) @@ -2041,6 +2064,11 @@ mt7996_mcu_add_rate_ctrl_fixed(struct mt7996_dev *dev, }
return 0; + +error_unlock: + rcu_read_unlock(); + + return -ENODEV; }
static void @@ -2159,6 +2187,7 @@ int mt7996_mcu_add_rate_ctrl(struct mt7996_dev *dev, struct mt7996_sta_link *msta_link, u8 link_id, bool changed) { + struct mt7996_sta *msta = msta_link->sta; struct sk_buff *skb; int ret;
@@ -2185,8 +2214,7 @@ int mt7996_mcu_add_rate_ctrl(struct mt7996_dev *dev, if (ret) return ret;
- return mt7996_mcu_add_rate_ctrl_fixed(dev, link_sta, link, msta_link, - link_id); + return mt7996_mcu_add_rate_ctrl_fixed(dev, msta, vif, link_id); }
static int