From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 67C072BF00D for ; Mon, 2 Feb 2026 07:54:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=210.61.82.184 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770018863; cv=none; b=ANBItHFS5rHwDGFmSRWmjp5eQC8NJrxd4Gt5vaFkQiVsz2BdlacE89AraPCLolrR1VNIhyj9LstYsPOT1aZ9i8sOjHVoHyXofwWu6raGEQenpFpM4BB1Nfzk8FmUbxHyyRu5fLQGSL0i7QILT9x4ce9rmZhoIlqoyQXdnuFFPyE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770018863; c=relaxed/simple; bh=xY3gIEDtbUKVWyqHCKB8z609xPAyMeNSP70oEhxUrVI=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=nOaNLINjJvhxoJFquL2N3VdjTPFfRr+CsihMSciayJCftqQZpRfHiQEzLZ5JMN8Hy1VCWlkr21Zm/5pZJu21UOK2XeHFHx/E6lnbQPvColnYGtjqTj7gCZKx4BAWHdFXZ/nrFvESulIl4PUWdzf4d/yi6zJGd+0QWRX6R/7tjlk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mediatek.com; spf=pass smtp.mailfrom=mediatek.com; dkim=pass (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b=jfBoHWis; arc=none smtp.client-ip=210.61.82.184 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mediatek.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mediatek.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="jfBoHWis" X-UUID: 5f52a626000c11f1b7fc4fdb8733b2bc-20260202 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=XAiHFASdcnSj6/esay44eO8OXUn72eajlw6VRifcypY=; b=jfBoHWisZCHbXpClPxAt7xg2rEJBEiVT/6ch+3f0ZN+8N3f9rdewimA+EFsV20374Df+/iNcNQtU8w4xl3rxGCZcuOgXoOrKOANjZSnniZ0IWtiEKh3nwGpIhEmpCIA9zUtxoBaBws5bGCLooDnso2IN8CSOScn4GmdLc2/0KOs=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.11,REQID:78c52cb0-5046-4ef2-b75f-1019c590ff9d,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:89c9d04,CLOUDID:b7d839f0-16bd-4243-b4ca-b08ca08ab1d8,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102|836|888|898,TC:-5,Content:0|15|5 0,EDM:-3,IP:nil,URL:0,File:130,RT:0,Bulk:nil,QS:nil,BEC:-1,COL:0,OSI:0,OSA :0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: 5f52a626000c11f1b7fc4fdb8733b2bc-20260202 Received: from mtkmbs11n2.mediatek.inc [(172.21.101.187)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1985799148; Mon, 02 Feb 2026 15:54:16 +0800 Received: from mtkmbs11n1.mediatek.inc (172.21.101.185) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.29; Mon, 2 Feb 2026 15:54:15 +0800 Received: from mtksitap99.mediatek.inc (10.233.130.16) by mtkmbs11n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.2562.29 via Frontend Transport; Mon, 2 Feb 2026 15:54:15 +0800 From: Shayne Chen To: Felix Fietkau CC: linux-wireless , Lorenzo Bianconi , Ryder Lee , Evelyn Tsai , Money Wang , linux-mediatek , Shayne Chen Subject: [PATCH 1/5] wifi: mt76: fix potential deadlock caused by rx_lock Date: Mon, 2 Feb 2026 15:53:06 +0800 Message-ID: <20260202075311.365673-1-shayne.chen@mediatek.com> X-Mailer: git-send-email 2.45.2 Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-MTK: N A deadlock will occur if both of the following conditions are met, because they each attempt to acquire the rx_lock: - mac80211 receives an unexpected BAR control frame, which triggers a BA deletion - A transmission failure happens due to an abnormality in DMA Since ieee80211_tx_status_ext() is primarily used to address AQL issues, avoid potential deadlocks by restricting calls to ieee80211_tx_status_ext only for data frames. Fixes: 94e4f5794627 ("mt76: dma: use ieee80211_tx_status_ext to free packets when tx fails") Reviewed-by: Money Wang Signed-off-by: Shayne Chen --- drivers/net/wireless/mediatek/mt76/dma.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c index 2d133ace7c33..928709f4a206 100644 --- a/drivers/net/wireless/mediatek/mt76/dma.c +++ b/drivers/net/wireless/mediatek/mt76/dma.c @@ -648,6 +648,8 @@ mt76_dma_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q, .skb = skb, }; struct mt76_dev *dev = phy->dev; + struct ieee80211_tx_info *info; + struct ieee80211_hdr *hdr; struct ieee80211_hw *hw; int len, n = 0, ret = -ENOMEM; struct mt76_txwi_cache *t; @@ -736,9 +738,16 @@ mt76_dma_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q, free_skb: status.skb = tx_info.skb; hw = mt76_tx_status_get_hw(dev, tx_info.skb); - spin_lock_bh(&dev->rx_lock); - ieee80211_tx_status_ext(hw, &status); - spin_unlock_bh(&dev->rx_lock); + hdr = (struct ieee80211_hdr *)tx_info.skb->data; + info = IEEE80211_SKB_CB(tx_info.skb); + if ((info->flags & IEEE80211_TX_CTL_HW_80211_ENCAP) || + ieee80211_is_data(hdr->frame_control)) { + spin_lock_bh(&dev->rx_lock); + ieee80211_tx_status_ext(hw, &status); + spin_unlock_bh(&dev->rx_lock); + } else { + ieee80211_free_txskb(hw, tx_info.skb); + } return ret; } -- 2.51.0