From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp134-25.sina.com.cn (smtp134-25.sina.com.cn [180.149.134.25]) (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 4BB941CFBE for ; Sat, 1 Jun 2024 09:07:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=180.149.134.25 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717232851; cv=none; b=h3jzgFXJkkqQo095gYWZxO7/1bR72xbIEDNIz4bT5C0ThvMIWFWh4CXMLWZsKDzTMPkATtYpfioy10AB3V13U0HjZcooQqOSkm3+fP7seVAJHAq7pbNERzfPWSEEdo20W+QaRjCS4BoGwDc1lk9T02tVbTFzA3+RB3ruy6zJyt4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717232851; c=relaxed/simple; bh=8mispSm5LAS1dd6YXjvy47vFNymtXBnRasSceVyclCQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=h4hde41HUMvXIcO/JqvlwNukqLNFMGo7poSeaLwS1zGIGWkGQHbpU11WxgsSGyh6Kb8pjvyblzCivIKJJPX7FsDjnM17SmU0WjMC0DAH4ABJRo+R0+ZQO/zfwy3hNGH265Dlhiy68a95xuBYCv3jZVcNJH7te47ba2rLUVGXg6w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; arc=none smtp.client-ip=180.149.134.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([113.118.68.165]) by sina.com (10.185.250.21) with ESMTP id 665AE4C00000105E; Sat, 1 Jun 2024 17:07:14 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 8807393408336 X-SMAIL-UIID: 8CE89FD4BCE94F99AD68A663130A9332-20240601-170714-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [mm?] INFO: rcu detected stall in kcompactd (2) Date: Sat, 1 Jun 2024 17:07:02 +0800 Message-Id: <20240601090702.3550-1-hdanton@sina.com> In-Reply-To: <0000000000002304860619cb8aa1@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Fri, 31 May 2024 20:17:26 -0700 > syzbot found the following issue on: > > HEAD commit: 2bfcfd584ff5 Merge tag 'pmdomain-v6.10-rc1' of git://git.k.. > git tree: upstream > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17314572980000 #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master --- x/net/mac80211/main.c +++ y/net/mac80211/main.c @@ -427,9 +427,12 @@ static void ieee80211_tasklet_handler(st { struct ieee80211_local *local = from_tasklet(local, t, tasklet); struct sk_buff *skb; + unsigned int loop = 0; while ((skb = skb_dequeue(&local->skb_queue)) || (skb = skb_dequeue(&local->skb_queue_unreliable))) { + if (++loop == 64) + return; switch (skb->pkt_type) { case IEEE80211_RX_MSG: /* Clear skb->pkt_type in order to not confuse kernel --