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From: Hillf Danton <hdanton@sina.com>
To: syzbot <syzbot+54594368fbd5a4f1754a@syzkaller.appspotmail.com>
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>
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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
--