WARNING: suspicious RCU usage (5)

WARNING: suspicious RCU usage (5)

Status: fixed on 2022/06/24 08:21
Reported-by: syzbot+9cbc6bed3a22f1d37395@syzkaller.appspotmail.com
Fix commit: f4e61f0c9add x86/kvm: Fix broken irq restoration in kvm_wait
First crash: 822d, last: 822d

Cause bisection: introduced by (bisect log) :
commit c2ff53d8049f30098153cd2d1299a44d7b124c57
Author: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Date: Thu Feb 18 20:50:02 2021 +0000

net: Add priv_flags for allow tx skb without linear

Crash: WARNING in kvm_wait (log)
Repro: C syz .config

▶ ▼ Discussions (1)

Title	Replies (including bot)	Last reply
[syzbot] WARNING: suspicious RCU usage (5)	2 (4)	2022/06/23 08:54

▶ ▼ Similar bugs (3)

Kernel	Title	Repro	Fix bisect	Count	Last	Reported	Patched	Status
upstream	WARNING: suspicious RCU usage			1	2584d	2584d	0/28	closed as invalid on 2017/08/17 16:34
upstream	WARNING: suspicious RCU usage (4) bpf trace	C	done	1	2203d	2202d	13/28	fixed on 2019/10/04 12:05
upstream	WARNING: suspicious RCU usage (3) mm			16	2480d	2481d	3/28	fixed on 2017/12/21 04:38

Sample crash report:

netdevsim netdevsim0 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0
=============================
WARNING: suspicious RCU usage
5.19.0-rc1-syzkaller-00254-ga5b00f5b78b7 #0 Not tainted
-----------------------------
net/ipv6/addrconf

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2022/06/13 22:49	net-old	a5b00f5b78b7	0d5abf15	.config	console log	report	syz	C			ci-upstream-net-this-kasan-gce	WARNING: suspicious RCU usage

* ~~Struck through~~ repros no longer work on HEAD.