[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.37' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 36.515834] BUG: sleeping function called from invalid context at mm/slab.h:422 [ 36.523545] in_atomic(): 1, irqs_disabled(): 1, pid: 8079, name: syz-executor600 [ 36.531438] 3 locks held by syz-executor600/8079: [ 36.536260] #0: 000000009bffcb92 (&ep->mtx){+.+.}, at: __se_sys_epoll_ctl+0x5d2/0x2b90 [ 36.544402] #1: 000000004d57ee7f (&dev->dev_mutex){+.+.}, at: v4l2_m2m_fop_poll+0x91/0x110 [ 36.552897] #2: 00000000cf77bdf7 (&(&q->done_lock)->rlock){....}, at: v4l2_m2m_poll+0x140/0x720 [ 36.561814] irq event stamp: 6608 [ 36.565253] hardirqs last enabled at (6607): [] _raw_spin_unlock_irqrestore+0x79/0xe0 [ 36.574853] hardirqs last disabled at (6608): [] _raw_spin_lock_irqsave+0x66/0xc0 [ 36.584127] softirqs last enabled at (6404): [] __do_softirq+0x678/0x980 [ 36.592597] softirqs last disabled at (6381): [] irq_exit+0x215/0x260 [ 36.600717] Preemption disabled at: [ 36.600721] [<0000000000000000>] (null) [ 36.609154] CPU: 0 PID: 8079 Comm: syz-executor600 Not tainted 4.19.211-syzkaller #0 [ 36.617017] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 36.626353] Call Trace: [ 36.628928] dump_stack+0x1fc/0x2ef [ 36.632540] ___might_sleep.cold+0x235/0x250 [ 36.636933] kmem_cache_alloc+0x26d/0x370 [ 36.641067] ep_ptable_queue_proc+0xaf/0x390 [ 36.645462] v4l2_m2m_poll+0x633/0x720 [ 36.649336] ? ep_poll_wakeup_proc+0x40/0x40 [ 36.653731] ? lockdep_hardirqs_on+0x3a8/0x5c0 [ 36.658299] ? v4l2_m2m_ctx_release+0x30/0x30 [ 36.662777] v4l2_m2m_fop_poll+0xa4/0x110 [ 36.666908] v4l2_poll+0x146/0x1f0 [ 36.670474] ? v4l2_mmap+0x1f0/0x1f0 [ 36.674167] ep_item_poll+0x14a/0x3e0 [ 36.677963] ? ep_eventpoll_poll+0x160/0x160 [ 36.682353] ? __se_sys_epoll_ctl+0xc5b/0x2b90 [ 36.686919] ? rcu_read_lock_sched_held+0x16c/0x1d0 [ 36.691919] __se_sys_epoll_ctl+0x1b04/0x2b90 [ 36.696403] ? ep_loop_check_proc+0x4d0/0x4d0 [ 36.700880] ? __fd_install+0x1eb/0x610 [ 36.704837] ? do_epoll_create+0x149/0x1c0 [ 36.709053] ? ep_poll_wakeup_proc+0x40/0x40 [ 36.713451] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 36.718799] ? trace_hardirqs_off_caller+0x6e/0x210 [ 36.723797] ? do_syscall_64+0x21/0x620 [ 36.727757] do_syscall_64+0xf9/0x620 [ 36.731583] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 36.736751] RIP: 0033:0x7fe37b3b71e9 [ 36.740463] 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 [ 36.759351] RSP: 002b:00007ffc7e718ac8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9 [