From patchwork Tue Sep 24 19:28:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Remi Pommarel X-Patchwork-Id: 830759 Received: from e3i110.smtp2go.com (e3i110.smtp2go.com [158.120.84.110]) (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 CBC7D1A4F0C for ; Tue, 24 Sep 2024 19:27:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=158.120.84.110 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727206048; cv=none; b=AdhkY3CIZg/LZQw+62GxuwwHnyL7RaREX2YR5U+QueCEoAwWNgP6RGD5WAJRalTMbp56qwVI2NVRLCLnpe+4cZw+riW7i/6OkbbdK0c28GjhoccLVKQNTyqcCdhRMppsyZFCcAQbjBdsHkEvKlmQCJNVlK+rT08qNbV70PEHEoM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727206048; c=relaxed/simple; bh=9gCvAmkQ+McMEqsM1XwBcX6PfPT1TaDQAb9TmK5M5vA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=kQmLAQa0YvODdXUEeYKm58WHeIgGULrr/F/wp3ww1Bsn0FnI4o8CcX+vWQYPlxjQ9yANs8ZETAMsZuxdKAA4CGBUemuROy/WogUSTPYxqF12XIqDQHtLUtM49K+MRX//Ut+FkOicYuuQlFDyEef9J1A//7MEHtETd38BnsojrG0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=triplefau.lt; spf=pass smtp.mailfrom=em510616.triplefau.lt; dkim=pass (2048-bit key) header.d=smtpservice.net header.i=@smtpservice.net header.b=ydr1nkcq; dkim=pass (2048-bit key) header.d=triplefau.lt header.i=@triplefau.lt header.b=ga++934y; arc=none smtp.client-ip=158.120.84.110 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=triplefau.lt Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=em510616.triplefau.lt Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=smtpservice.net header.i=@smtpservice.net header.b="ydr1nkcq"; dkim=pass (2048-bit key) header.d=triplefau.lt header.i=@triplefau.lt header.b="ga++934y" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=smtpservice.net; i=@smtpservice.net; q=dns/txt; s=a1-4; t=1727206039; h=feedback-id : x-smtpcorp-track : date : message-id : to : subject : from : reply-to : sender : list-unsubscribe : list-unsubscribe-post; bh=r7mBfgbkSHPGjlsNaa8FSid+n6LiX6fLZWRk2WuEUPE=; b=ydr1nkcqmYqIlG8qlYfNHpdDrfgYvNstOb58GO+lCgzA6BEymXhZ3JKqEvbJlB+cF9TY+ Dc7ubGwzAfBSvAqy1S8Ry032EBwn4dmLlzzwu/oEslZeullE4bxffyeET+s1mi4c2QKc85I h3Ve1VESTKC7nRgBFl2CVOy12FDovDul2I04tU4p8bJhuuHOZwNAVjBxoGF3a/RhIvvwrA+ SKGjao1gwld6GMHgS9RCtMFcFX95lQaPTcCFr71qOO3OypWlvKH0msbQRUnmIzj7Goq0wiF /Cs7Wa7rw4q0yL5SF93vfDM8kwux7VubPVQ+4HZsLH4CcD0vkt5WbIXLumnQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=triplefau.lt; i=@triplefau.lt; q=dns/txt; s=s510616; t=1727206039; h=from : subject : to : message-id : date; bh=r7mBfgbkSHPGjlsNaa8FSid+n6LiX6fLZWRk2WuEUPE=; b=ga++934ywl8PpQ7kK9wvykDn6g3lvV7ldGiqy+sUJ12Jn/YiC0G1PD+TIPq/E97Uw/2/8 JeBS44fJS1Nw+Mr6eGri0V6t4u27kPcRuRan3cb0wP04pSGMBFJoz0ccLtkUyYFNj6ON/Pr eZlHqJR+FHgzOiE+1U6yF7wIM4OXOA1LMBj3DDlQRvNA8VtvemPeyt+NbgwuSVIvWmGr5rs FiYasX9DzWFC0h6C+RS5a10xhfXFShJcPfbf6oQawVYdoQ8XobAw7BnAPNbQrL8GeCFN6ve GmgTi5noveVwmQrdUSYbbcHzoc+ZII7p0lAcL59dfpcXhRmZMdemJVMEkgMA== Received: from [10.12.239.196] (helo=localhost) by smtpcorp.com with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.97.1-S2G) (envelope-from ) id 1stBBs-4o5NDgruoYJ-mxiC; Tue, 24 Sep 2024 19:27:16 +0000 From: Remi Pommarel To: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Johannes Berg , Nicolas Cavallari , Nicolas Escande , Remi Pommarel Subject: [PATCH 2/2] wifi: mac80211: Convert color collision detection to wiphy work Date: Tue, 24 Sep 2024 21:28:05 +0200 Message-Id: <20240924192805.13859-3-repk@triplefau.lt> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20240924192805.13859-1-repk@triplefau.lt> References: <20240924192805.13859-1-repk@triplefau.lt> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Report-Abuse: Please forward a copy of this message, including all headers, to Feedback-ID: 510616m:510616apGKSTK:510616seT2XkfLmR X-smtpcorp-track: NyqcqcWION9C.YbycEVi8QH6j.yY45yQ4zncR Call to ieee80211_color_collision_detection_work() needs wiphy lock to be held (see lockdep assert in cfg80211_bss_color_notify()). Not locking wiphy causes the following lockdep error: WARNING: CPU: 2 PID: 42 at net/wireless/nl80211.c:19505 cfg80211_bss_color_notify+0x1a4/0x25c Modules linked in: CPU: 2 PID: 42 Comm: kworker/u8:3 Tainted: G W 6.4.0-02327-g36c6cb260481 #1048 Hardware name: Workqueue: phy1 ieee80211_color_collision_detection_work pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : cfg80211_bss_color_notify+0x1a4/0x25c lr : cfg80211_bss_color_notify+0x1a0/0x25c sp : ffff000002947d00 x29: ffff000002947d00 x28: ffff800008e1a000 x27: ffff000002bd4705 x26: ffff00000d034000 x25: ffff80000903cf40 x24: 0000000000000000 x23: ffff00000cb70720 x22: 0000000000800000 x21: ffff800008dfb008 x20: 000000000000008d x19: ffff00000d035fa8 x18: 0000000000000010 x17: 0000000000000001 x16: 000003564b1ce96a x15: 000d69696d057970 x14: 000000000000003b x13: 0000000000000001 x12: 0000000000040000 x11: 0000000000000001 x10: ffff80000978f9c0 x9 : ffff0000028d3174 x8 : ffff800008e30000 x7 : 0000000000000000 x6 : 0000000000000028 x5 : 000000000002f498 x4 : ffff00000d034a80 x3 : 0000000000800000 x2 : ffff800016143000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: cfg80211_bss_color_notify+0x1a4/0x25c ieee80211_color_collision_detection_work+0x20/0x118 process_one_work+0x294/0x554 worker_thread+0x70/0x440 kthread+0xf4/0xf8 ret_from_fork+0x10/0x20 irq event stamp: 77372 hardirqs last enabled at (77371): [] _raw_spin_unlock_irq+0x2c/0x4c hardirqs last disabled at (77372): [] el1_dbg+0x20/0x48 softirqs last enabled at (77350): [] batadv_send_outstanding_bcast_packet+0xb8/0x120 softirqs last disabled at (77348): [] batadv_send_outstanding_bcast_packet+0x80/0x120 The wiphy lock cannot be taken directly from color collision detection delayed work (ieee80211_color_collision_detection_work()) because this work is cancel_delayed_work_sync() under this wiphy lock causing a potential deadlock( see [0] for details). To fix that ieee80211_color_collision_detection_work() could be converted to a wiphy work and cancel_delayed_work_sync() can be simply replaced by wiphy_delayed_work_cancel() serving the same purpose under wiphy lock. This could potentially fix [1]. [0]: https://lore.kernel.org/linux-wireless/D4A40Q44OAY2.W3SIF6UEPBUN@freebox.fr/ [1]: https://lore.kernel.org/lkml/000000000000612f290618eee3e5@google.com/ Reported-by: Nicolas Escande Signed-off-by: Remi Pommarel --- net/mac80211/cfg.c | 17 +++++++++-------- net/mac80211/ieee80211_i.h | 5 +++-- net/mac80211/link.c | 7 ++++--- 3 files changed, 16 insertions(+), 13 deletions(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index b02b84ce2130..09025d59cdbe 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -4819,12 +4819,12 @@ void ieee80211_color_change_finalize_work(struct wiphy *wiphy, ieee80211_color_change_finalize(link); } -void ieee80211_color_collision_detection_work(struct work_struct *work) +void ieee80211_color_collision_detection_work(struct wiphy *wiphy, + struct wiphy_work *work) { - struct delayed_work *delayed_work = to_delayed_work(work); struct ieee80211_link_data *link = - container_of(delayed_work, struct ieee80211_link_data, - color_collision_detect_work); + container_of(work, struct ieee80211_link_data, + color_collision_detect_work.work); struct ieee80211_sub_if_data *sdata = link->sdata; cfg80211_obss_color_collision_notify(sdata->dev, link->color_bitmap, @@ -4877,7 +4877,8 @@ ieee80211_obss_color_collision_notify(struct ieee80211_vif *vif, return; } - if (delayed_work_pending(&link->color_collision_detect_work)) { + if (wiphy_delayed_work_pending(sdata->local->hw.wiphy, + &link->color_collision_detect_work)) { rcu_read_unlock(); return; } @@ -4886,9 +4887,9 @@ ieee80211_obss_color_collision_notify(struct ieee80211_vif *vif, /* queue the color collision detection event every 500 ms in order to * avoid sending too much netlink messages to userspace. */ - ieee80211_queue_delayed_work(&sdata->local->hw, - &link->color_collision_detect_work, - msecs_to_jiffies(500)); + wiphy_delayed_work_queue(sdata->local->hw.wiphy, + &link->color_collision_detect_work, + msecs_to_jiffies(500)); rcu_read_unlock(); } diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index a3485e4c6132..8650b3e8f1a9 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -1051,7 +1051,7 @@ struct ieee80211_link_data { } csa; struct wiphy_work color_change_finalize_work; - struct delayed_work color_collision_detect_work; + struct wiphy_delayed_work color_collision_detect_work; u64 color_bitmap; /* context reservation -- protected with wiphy mutex */ @@ -2004,7 +2004,8 @@ int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev, /* color change handling */ void ieee80211_color_change_finalize_work(struct wiphy *wiphy, struct wiphy_work *work); -void ieee80211_color_collision_detection_work(struct work_struct *work); +void ieee80211_color_collision_detection_work(struct wiphy *wiphy, + struct wiphy_work *work); /* interface handling */ #define MAC80211_SUPPORTED_FEATURES_TX (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | \ diff --git a/net/mac80211/link.c b/net/mac80211/link.c index 1a211b8d4057..67f65ff79a71 100644 --- a/net/mac80211/link.c +++ b/net/mac80211/link.c @@ -41,8 +41,8 @@ void ieee80211_link_init(struct ieee80211_sub_if_data *sdata, ieee80211_csa_finalize_work); wiphy_work_init(&link->color_change_finalize_work, ieee80211_color_change_finalize_work); - INIT_DELAYED_WORK(&link->color_collision_detect_work, - ieee80211_color_collision_detection_work); + wiphy_delayed_work_init(&link->color_collision_detect_work, + ieee80211_color_collision_detection_work); INIT_LIST_HEAD(&link->assigned_chanctx_list); INIT_LIST_HEAD(&link->reserved_chanctx_list); @@ -70,7 +70,8 @@ void ieee80211_link_stop(struct ieee80211_link_data *link) if (link->sdata->vif.type == NL80211_IFTYPE_STATION) ieee80211_mgd_stop_link(link); - cancel_delayed_work_sync(&link->color_collision_detect_work); + wiphy_delayed_work_cancel(link->sdata->local->hw.wiphy, + &link->color_collision_detect_work); wiphy_work_cancel(link->sdata->local->hw.wiphy, &link->color_change_finalize_work); wiphy_work_cancel(link->sdata->local->hw.wiphy,