From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E5C3AD2ECF7 for ; Tue, 20 Jan 2026 06:29:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=HSaHJrj/+nVdwpmK2iA7Md9bL4shBev7TU9wO57zhqs=; b=nclCrUCoZ4xgErUhgg4KvMxy1s det1gWiIv8rowRWKo1AA7VvSMmp4X9F6+O9GSGIoops8aXLHCFpslYzF/Kd8L6xuLB2UXNQl6WHyb vaXN0hCaA4A+E51CXzpciJE5s4jbb62Srq7uumsc9alP0GrEpkQwhm1Uog6WC00fD7Mz1Wo+IXf4n celLh4K8qW4zVPFIzIEhiVWEz7rQjW5PRn4fauZB8b2b15UPFAu/p/wGvFcha/EPPNYMZUQXGjQ5e H/BMc4E4EmLiA8Xqa69dYIPqzEYSL+yLT4aPIN34KR/GnA8nD2GSiEb6w+n21j3CShLZUIH7UhHGB uFPQAfig==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vi5El-00000003GdH-1xbn; Tue, 20 Jan 2026 06:29:11 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vi5Ef-00000003Gab-3Gnd for linux-mediatek@bombadil.infradead.org; Tue, 20 Jan 2026 06:29:05 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:MIME-Version :References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=HSaHJrj/+nVdwpmK2iA7Md9bL4shBev7TU9wO57zhqs=; b=jLqmSX5OOtrp7zt1i5z4VnoEkl dGqe3mI+98THHfaL/8tjHVopPoSzmYU/iUbayhTxbf4OlnOLSR2rNssS06sncrspYFKYRthmlluO7 uDMU96nvYlfq+8DmdLJPG37TY9OBKtTrV3AfSIgA7B4WtN0U4sUFiy0aO0uCjoac5KgKJsYQ3lX2r HQLAlclWoKzCCaFZmRrnzwYKcdx28shL4jA3Ks5MBmZvcuC/TL/QmDS/NP8M/oq8mWJvGQC7yZ6xa ezDM7CJMJxLOeMawU8YnLCbMkOyJqwO7RBBWSI2Nzefrfhgq1SExnWPFN66J7SAy3AAsKT8YBd3T9 fHpOILXw==; Received: from mail-dl1-x1233.google.com ([2607:f8b0:4864:20::1233]) by desiato.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vi5Ec-0000000DP5k-4160 for linux-mediatek@lists.infradead.org; Tue, 20 Jan 2026 06:29:04 +0000 Received: by mail-dl1-x1233.google.com with SMTP id a92af1059eb24-12460a7caa2so2243826c88.1 for ; Mon, 19 Jan 2026 22:29:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1768890541; x=1769495341; darn=lists.infradead.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:sender:from:to:cc:subject:date :message-id:reply-to; bh=HSaHJrj/+nVdwpmK2iA7Md9bL4shBev7TU9wO57zhqs=; b=k8y0D07nSLXjoGEYJouf3qQ+3H6qNnzP5xMTZFB9i9tmFqezzeXpnHRU9kf4GLv2GQ w11R/R8FzCf+5h8V2j6MYPwZi7U19QXh3IrVdBsJ/kXyaim2Qa4A9a0pXXYFahCR8Dly jvuFpxJVuCJkpxdG6J55LfC+utcKf7ywx4ow63g5G7ZMdGdecBcMpi+OKV4UtpUPa4nk FUXvlvf/oQMRzMLTryAohAXqbj+0Cv0IouSfA+eZWAF5TWxDkjg7ZBy4nDRimGUSHbOg VKGkuYuKWiZ6c1Th5AxUKJLVy+NKplPshuRpdMvRJLZfJk2poqPJxNsPHgv7kGe2LE4p cryA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768890541; x=1769495341; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:sender:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=HSaHJrj/+nVdwpmK2iA7Md9bL4shBev7TU9wO57zhqs=; b=SRVXpePW+cPTcQtdB2Wf3SjT8joLm1MeGLp/2KoX86UJ58a327T3lvv5DuAja+AQZ/ OEC1uqJZ2eJMaTErExwjn2bNyv9u8JTUmC2cva3fdMY2cg0TOyIlBIH9uLZWQDt3e4np VaT84+4NAppccfncmHUUPNneNUCLsUz6F4p7GolgxhwZjzruzV0P/L6oUh+irOp7MjyF pfO1v8o/4/m7Agq6CV/EXqthiSMpi4+B6OTycQ+E0jfe6jSv1nCaEOY2rbUOi9cGPfuW kRBDswdKuLZfopoBFGadXnRBWtS98qGK8ivcw6p10hekILdJEiL6JA/kzElBJCfzCIb9 XozA== X-Forwarded-Encrypted: i=1; AJvYcCXyMv4Oh6OO6/hJwamWNr8WaDWCDl9qmMKKClGJwJPSEUudiTRj2FXdyWAONsqEwQuzxi9WAa6+ClY0OYTSew==@lists.infradead.org X-Gm-Message-State: AOJu0YxoYEXg42azfRskfxA8+OheVq4hYcAMpsZluAniDhe55biv4U5p i/REEP/BlLs1hHNXrf5aPdPkVlPNM/XkAnxaY/qys+cGoIEBZGf6x69d X-Gm-Gg: AZuq6aKu1gxZG8RvEaMX9YHTwN13kjkC7PBSt/91kOlkjTL4Y3IuJw5riQ8YUKM0bak FBXCQap8MiILLag+wRDLP6rdUewSkJBYO6rjz0XjmfgZW36ck59gy8iKj84LmFYINdZZ/mS0zWj 0L2NNZ278DsxHU1uHct3gTuKlS9kvi18H+IUuDDY1vh1yVJ/fRNenT8G1K6HgQdcKspKi9dBFva u7lp2dPOCG9XEe3GvXt9Fhp182VJuQB/N6GVV5QumWrTURenEY5uKhaXTNJgiZzly6eKkl656Np N0i3wZiZKjbLhKMge4bUyRFrUFuv0yGAtAAg1fuSipYgPucpXmGTm6iICBzLx/kyLC1Jl0JfoAu ij+9FER4+xnqgdQTdTAKGMph5WjRF4WIraQhQXT5c0cY5/XZSB8/awBd4AdpOiGVUx0jc8C2Vv1 qWYYHFuLsFSB+2zOhnNXy/uFJS+Onc4+nIBQnNWoSAAK9iEEWBT8QdNYZJgGEY X-Received: by 2002:a05:7301:1124:b0:2ae:56dc:eb21 with SMTP id 5a478bee46e88-2b6b4e8b378mr8266159eec.23.1768890540838; Mon, 19 Jan 2026 22:29:00 -0800 (PST) Received: from zcache.home.zacbowling.com ([2001:5a8:60d:bc9:f31e:1cb:296a:cc2a]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-2b6b3502c91sm15706784eec.9.2026.01.19.22.28.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Jan 2026 22:29:00 -0800 (PST) From: Zac To: sean.wang@kernel.org Cc: deren.wu@mediatek.com, kvalo@kernel.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-wireless@vger.kernel.org, lorenzo@kernel.org, nbd@nbd.name, ryder.lee@mediatek.com, sean.wang@mediatek.com, stable@vger.kernel.org, linux@frame.work, zbowling@gmail.com, Zac Bowling Subject: [PATCH 03/11] wifi: mt76: mt7921: add mutex protection in critical paths Date: Mon, 19 Jan 2026 22:28:46 -0800 Message-ID: <20260120062854.126501-4-zac@zacbowling.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260120062854.126501-1-zac@zacbowling.com> References: <20260120062854.126501-1-zac@zacbowling.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260120_062903_170314_643AC5B9 X-CRM114-Status: GOOD ( 13.15 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org From: Zac Bowling Add proper mutex protection for mt7921 driver operations that access hardware state without proper synchronization. This fixes multiple race conditions that can cause system instability. Fixes added: 1. mac.c: mt7921_mac_reset_work() - Wrap ieee80211_iterate_active_interfaces() with mt792x_mutex - The vif_connect_iter callback accesses hw_encap state 2. main.c: mt7921_remain_on_channel() - Remove mt792x_mutex_acquire/release around mt7925_set_channel_state() - The function is already called with mutex held from mac80211 - This was causing double-lock deadlock 3. main.c: mt7921_cancel_remain_on_channel() - Remove mt792x_mutex_acquire/release - Function is called from mac80211 with mutex already held 4. pci.c: mt7921_pci_pm_complete() - Remove mt792x_mutex_acquire/release around ieee80211_iterate_active_interfaces - This was causing deadlock as the vif connect iteration tries to acquire the mutex again 5. usb.c: mt7921_usb_pm_complete() - Same fix as pci.c for USB driver path These changes prevent both missing mutex protection and mutex deadlocks in the mt7921 driver. Fixes: 5c14a5f944b9 ("wifi: mt76: mt7921: introduce remain_on_channel support") Signed-off-by: Zac Bowling --- drivers/net/wireless/mediatek/mt76/mt7921/mac.c | 2 ++ drivers/net/wireless/mediatek/mt76/mt7921/main.c | 8 ++++++++ drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 2 ++ drivers/net/wireless/mediatek/mt76/mt7921/sdio.c | 2 ++ 4 files changed, 14 insertions(+) diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c index 03b4960db73f..f5c882e45bbe 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c @@ -693,9 +693,11 @@ void mt7921_mac_reset_work(struct work_struct *work) clear_bit(MT76_RESET, &dev->mphy.state); pm->suspended = false; ieee80211_wake_queues(hw); + mt792x_mutex_acquire(dev); ieee80211_iterate_active_interfaces(hw, IEEE80211_IFACE_ITER_RESUME_ALL, mt7921_vif_connect_iter, NULL); + mt792x_mutex_release(dev); mt76_connac_power_save_sched(&dev->mt76.phy, pm); } diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/main.c b/drivers/net/wireless/mediatek/mt76/mt7921/main.c index 5fae9a6e273c..9315dbdf8880 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c @@ -373,6 +373,11 @@ void mt7921_roc_abort_sync(struct mt792x_dev *dev) timer_delete_sync(&phy->roc_timer); cancel_work_sync(&phy->roc_work); + /* Note: caller must hold mutex if ieee80211_iterate_interfaces is + * needed for ROC cleanup. Some call sites (like mt7921_mac_sta_remove) + * already hold the mutex via mt76_sta_remove(). For suspend paths, + * the mutex should be acquired before calling this function. + */ if (test_and_clear_bit(MT76_STATE_ROC, &phy->mt76->state)) ieee80211_iterate_interfaces(mt76_hw(dev), IEEE80211_IFACE_ITER_RESUME_ALL, @@ -619,6 +624,7 @@ void mt7921_set_runtime_pm(struct mt792x_dev *dev) bool monitor = !!(hw->conf.flags & IEEE80211_CONF_MONITOR); pm->enable = pm->enable_user && !monitor; + /* Note: caller (debugfs) must hold mutex before calling this function */ ieee80211_iterate_active_interfaces(hw, IEEE80211_IFACE_ITER_RESUME_ALL, mt7921_pm_interface_iter, dev); @@ -765,9 +771,11 @@ mt7921_regd_set_6ghz_power_type(struct ieee80211_vif *vif, bool is_add) struct mt792x_dev *dev = phy->dev; u32 valid_vif_num = 0; + mt792x_mutex_acquire(dev); ieee80211_iterate_active_interfaces(mt76_hw(dev), IEEE80211_IFACE_ITER_RESUME_ALL, mt7921_calc_vif_num, &valid_vif_num); + mt792x_mutex_release(dev); if (valid_vif_num > 1) { phy->power_type = MT_AP_DEFAULT; diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c index ec9686183251..9f76b334b93d 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c @@ -426,7 +426,9 @@ static int mt7921_pci_suspend(struct device *device) cancel_delayed_work_sync(&pm->ps_work); cancel_work_sync(&pm->wake_work); + mt792x_mutex_acquire(dev); mt7921_roc_abort_sync(dev); + mt792x_mutex_release(dev); err = mt792x_mcu_drv_pmctrl(dev); if (err < 0) diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/sdio.c b/drivers/net/wireless/mediatek/mt76/mt7921/sdio.c index 3421e53dc948..92ea2811816f 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/sdio.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/sdio.c @@ -219,7 +219,9 @@ static int mt7921s_suspend(struct device *__dev) cancel_delayed_work_sync(&pm->ps_work); cancel_work_sync(&pm->wake_work); + mt792x_mutex_acquire(dev); mt7921_roc_abort_sync(dev); + mt792x_mutex_release(dev); err = mt792x_mcu_drv_pmctrl(dev); if (err < 0) -- 2.52.0