BUG: sleeping function called from invalid context in console

BUG: sleeping function called from invalid context in console_lock (2)
Status: upstream: reported C repro on 2021/06/07 15:46
Reported-by: syzbot+dbac96d8e73b61aa559c@syzkaller.appspotmail.com
First crash: 135d, last: 15d

Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: BUG: sleeping function called from invalid context in do_con_write (log)
Repro: C syz .config

Fix bisection: the fix commit could be any of (bisect log):
614124bea77e Linux 5.13-rc5
f55966571d5e Merge tag 'drm-next-2021-07-08-1' of git://anongit.freedesktop.org/drm/drm

similar bugs (1):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	BUG: sleeping function called from invalid context in console_lock				1	519d	519d	0/22	auto-closed as invalid on 2020/09/14 09:18

Sample crash report:

BUG: sleeping function called from invalid context at kernel/printk/printk.c:2460
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 8444, name: syz-executor530
3 locks held by syz-executor530/8444:
 #0: ffff888027e26098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252
 #1: ffff888027e26468 (&tty->flow.lock){....}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:379 [inline]
 #1: ffff888027e26468 (&tty->flow.lock){....}-{2:2}, at: n_tty_ioctl_helper+0xc1/0x2d0 drivers/tty/tty_ioctl.c:881
 #2: ffff888027e26098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1d/0x80 drivers/tty/tty_ldisc.c:273
irq event stamp: 17202
hardirqs last  enabled at (17201): [<ffffffff892cf890>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
hardirqs last  enabled at (17201): [<ffffffff892cf890>] _raw_spin_unlock_irqrestore+0x50/0x70 kernel/locking/spinlock.c:191
hardirqs last disabled at (17202): [<ffffffff892cf5f1>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:126 [inline]
hardirqs last disabled at (17202): [<ffffffff892cf5f1>] _raw_spin_lock_irq+0x41/0x50 kernel/locking/spinlock.c:167
softirqs last  enabled at (16948): [<ffffffff8146492e>] invoke_softirq kernel/softirq.c:432 [inline]
softirqs last  enabled at (16948): [<ffffffff8146492e>] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636
softirqs last disabled at (16923): [<ffffffff8146492e>] invoke_softirq kernel/softirq.c:432 [inline]
softirqs last disabled at (16923): [<ffffffff8146492e>] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 0 PID: 8444 Comm: syz-executor530 Not tainted 5.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105
 ___might_sleep.cold+0x1f1/0x237 kernel/sched/core.c:9154
 console_lock+0x19/0x80 kernel/printk/printk.c:2460
 do_con_write+0x10f/0x1e40 drivers/tty/vt/vt.c:2868
 con_write+0x21/0x40 drivers/tty/vt/vt.c:3255
 n_hdlc_send_frames+0x24b/0x490 drivers/tty/n_hdlc.c:290
 tty_wakeup+0xe1/0x120 drivers/tty/tty_io.c:534
 __start_tty drivers/tty/tty_io.c:806 [inline]
 __start_tty+0xfb/0x130 drivers/tty/tty_io.c:799
 n_tty_ioctl_helper+0x2a3/0x2d0 drivers/tty/tty_ioctl.c:884
 n_hdlc_tty_ioctl+0xe4/0x360 drivers/tty/n_hdlc.c:633
 tty_ioctl+0xef9/0x1600 drivers/tty/tty_io.c:2814
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl fs/ioctl.c:1055 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x43f159
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48

Crashes (7):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci-upstream-kasan-gce	2021/08/05 23:20	upstream	902e7f373fff	d2d6e680	.config	log	report	syz	C		BUG: sleeping function called from invalid context in console_lock
ci-upstream-kasan-gce	2021/06/07 23:16	upstream	614124bea77e	e59537be	.config	log	report	syz	C		BUG: sleeping function called from invalid context in console_lock
ci-upstream-kasan-gce	2021/06/06 00:29	upstream	e5220dd16778	500c2339	.config	log	report	syz	C		BUG: sleeping function called from invalid context in console_lock
ci-upstream-kasan-gce-selinux-root	2021/09/27 03:25	upstream	996148ee05d0	78494d16	.config	log	report			info	BUG: sleeping function called from invalid context in console_lock
ci-upstream-kasan-gce-smack-root	2021/09/20 21:50	upstream	e4e737bb5c17	af796c18	.config	log	report			info	BUG: sleeping function called from invalid context in console_lock
ci-upstream-kasan-gce	2021/06/06 00:10	upstream	e5220dd16778	500c2339	.config	log	report			info	BUG: sleeping function called from invalid context in console_lock
ci-upstream-linux-next-kasan-gce-root	2021/10/03 07:07	linux-next	a25006a77348	db0f5787	.config	log	report			info	BUG: sleeping function called from invalid context in console_lock