syzbot

BUG: sleeping function called from invalid context at mm/slab.h:419
in_atomic(): 1, irqs_disabled(): 1, pid: 7980, name: syz-executor774
3 locks held by syz-executor774/7980:
 #0:  (&ep->mtx){+.+.}, at: [<ffffffff8196a296>] SYSC_epoll_ctl fs/eventpoll.c:2080 [inline]
 #0:  (&ep->mtx){+.+.}, at: [<ffffffff8196a296>] SyS_epoll_ctl+0x516/0x2780 fs/eventpoll.c:2002
 #1:  (&dev->dev_mutex){+.+.}, at: [<ffffffff84c03981>] v4l2_m2m_fop_poll+0x91/0x110 drivers/media/v4l2-core/v4l2-mem2mem.c:802
 #2:  (&(&q->done_lock)->rlock){....}, at: [<ffffffff84c02d36>] v4l2_m2m_poll+0x116/0x670 drivers/media/v4l2-core/v4l2-mem2mem.c:536
irq event stamp: 6648
hardirqs last  enabled at (6647): [<ffffffff8723f9d9>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
hardirqs last  enabled at (6647): [<ffffffff8723f9d9>] _raw_spin_unlock_irqrestore+0x79/0xe0 kernel/locking/spinlock.c:192
hardirqs last disabled at (6648): [<ffffffff8723f666>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
hardirqs last disabled at (6648): [<ffffffff8723f666>] _raw_spin_lock_irqsave+0x66/0xc0 kernel/locking/spinlock.c:160
softirqs last  enabled at (3068): [<ffffffff8760068b>] __do_softirq+0x68b/0x9ff kernel/softirq.c:314
softirqs last disabled at (3043): [<ffffffff81321d13>] invoke_softirq kernel/softirq.c:368 [inline]
softirqs last disabled at (3043): [<ffffffff81321d13>] irq_exit+0x193/0x240 kernel/softirq.c:409
Preemption disabled at:
[<          (null)>]           (null)
CPU: 1 PID: 7980 Comm: syz-executor774 Not tainted 4.14.258-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 ___might_sleep.cold+0x235/0x250 kernel/sched/core.c:6041
 slab_pre_alloc_hook mm/slab.h:419 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 kmem_cache_alloc+0x284/0x3c0 mm/slab.c:3550
 ep_ptable_queue_proc+0x9e/0x370 fs/eventpoll.c:1255
 poll_wait include/linux/poll.h:50 [inline]
 v4l2_m2m_poll+0x583/0x670 drivers/media/v4l2-core/v4l2-mem2mem.c:538
 v4l2_m2m_fop_poll+0xa4/0x110 drivers/media/v4l2-core/v4l2-mem2mem.c:804
 v4l2_poll+0x133/0x1d0 drivers/media/v4l2-core/v4l2-dev.c:342
 ep_item_poll fs/eventpoll.c:885 [inline]
 ep_insert fs/eventpoll.c:1490 [inline]
 SYSC_epoll_ctl fs/eventpoll.c:2117 [inline]
 SyS_epoll_ctl+0x14af/0x2780 fs/eventpoll.c:2002
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f73a66dc1e9
RSP: 002b:00007ffd74d8c338 EFLAGS: 00000246 ORIG_RAX: 00000000000