=============================
WARNING: suspicious RCU usage
4.15.0-rc7+ #183 Not tainted
-----------------------------
./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syz-executor3/9287:
 #0:  (&net->xfrm.xfrm_cfg_mutex){+.+.}, at: [<00000000c9cd6449>] xfrm_netlink_rcv+0x60/0x90 net/xfrm/xfrm_user.c:2598
 #1:  (rcu_read_lock){....}, at: [<00000000d6fd3009>] xfrm_state_get_afinfo+0x62/0x280 net/xfrm/xfrm_state.c:2157

stack backtrace:
CPU: 0 PID: 9287 Comm: syz-executor3 Not tainted 4.15.0-rc7+ #183
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+0x194/0x257 lib/dump_stack.c:53
 lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4585
 rcu_preempt_sleep_check include/linux/rcupdate.h:301 [inline]
 ___might_sleep+0x385/0x470 kernel/sched/core.c:6025
 __might_sleep+0x95/0x190 kernel/sched/core.c:6013
 slab_pre_alloc_hook mm/slab.h:419 [inline]
 slab_alloc mm/slab.c:3368 [inline]
 kmem_cache_alloc_trace+0x298/0x750 mm/slab.c:3608
 kmalloc include/linux/slab.h:499 [inline]
 call_modprobe kernel/kmod.c:80 [inline]
 __request_module+0x2e1/0xc20 kernel/kmod.c:171
 xfrm_get_type_offload net/xfrm/xfrm_state.c:317 [inline]
 __xfrm_init_state+0xa61/0xdd0 net/xfrm/xfrm_state.c:2257
 xfrm_state_construct net/xfrm/xfrm_user.c:590 [inline]
 xfrm_add_sa+0x1a09/0x33e0 net/xfrm/xfrm_user.c:646
 xfrm_user_rcv_msg+0x422/0x860 net/xfrm/xfrm_user.c:2591
 netlink_rcv_skb+0x224/0x470 net/netlink/af_netlink.c:2441
 xfrm_netlink_rcv+0x6f/0x90 net/xfrm/xfrm_user.c:2599
 netlink_unicast_kernel net/netlink/af_netlink.c:1308 [inline]
 netlink_unicast+0x4c4/0x6b0 net/netlink/af_netlink.c:1334
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1897
 sock_sendmsg_nosec net/socket.c:628 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:638
 ___sys_sendmsg+0x767/0x8b0 net/socket.c:2018
 __sys_sendmsg+0xe5/0x210 net/socket.c:2052
 SYSC_sendmsg net/socket.c:2063 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2059
 entry_SYSCALL_64_fastpath+0x23/0x9a
RIP: 0033:0x452ac9
RSP: 002b:00007f40b5017c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f40b5018700 RCX: 0000000000452ac9
RDX: 0000000000000000 RSI: 0000000020004000 RDI: 0000000000000013
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000
R13: 0000000000a2f7ef R14: 00007f40b50189c0 R15: 0000000000000000
BUG: sleeping function called from invalid context at mm/slab.h:419
in_atomic(): 1, irqs_disabled(): 0, pid: 9287, name: syz-executor3
2 locks held by syz-executor3/9287:
 #0:  (&net->xfrm.xfrm_cfg_mutex){+.+.}, at: [<00000000c9cd6449>] xfrm_netlink_rcv+0x60/0x90 net/xfrm/xfrm_user.c:2598
 #1:  (rcu_read_lock){....}, at: [<00000000d6fd3009>] xfrm_state_get_afinfo+0x62/0x280 net/xfrm/xfrm_state.c:2157
CPU: 0 PID: 9287 Comm: syz-executor3 Not tainted 4.15.0-rc7+ #183
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+0x194/0x257 lib/dump_stack.c:53
 ___might_sleep+0x2b2/0x470 kernel/sched/core.c:6060
 __might_sleep+0x95/0x190 kernel/sched/core.c:6013
 slab_pre_alloc_hook mm/slab.h:419 [inline]
 slab_alloc mm/slab.c:3368 [inline]
 kmem_cache_alloc_trace+0x298/0x750 mm/slab.c:3608
 kmalloc include/linux/slab.h:499 [inline]
 call_modprobe kernel/kmod.c:80 [inline]
 __request_module+0x2e1/0xc20 kernel/kmod.c:171
 xfrm_get_type_offload net/xfrm/xfrm_state.c:317 [inline]
 __xfrm_init_state+0xa61/0xdd0 net/xfrm/xfrm_state.c:2257
 xfrm_state_construct net/xfrm/xfrm_user.c:590 [inline]
 xfrm_add_sa+0x1a09/0x33e0 net/xfrm/xfrm_user.c:646
 xfrm_user_rcv_msg+0x422/0x860 net/xfrm/xfrm_user.c:2591
 netlink_rcv_skb+0x224/0x470 net/netlink/af_netlink.c:2441
 xfrm_netlink_rcv+0x6f/0x90 net/xfrm/xfrm_user.c:2599
 netlink_unicast_kernel net/netlink/af_netlink.c:1308 [inline]
 netlink_unicast+0x4c4/0x6b0 net/netlink/af_netlink.c:1334
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1897
 sock_sendmsg_nosec net/socket.c:628 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:638
 ___sys_sendmsg+0x767/0x8b0 net/socket.c:2018
 __sys_sendmsg+0xe5/0x210 net/socket.c:2052
 SYSC_sendmsg net/socket.c:2063 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2059
 entry_SYSCALL_64_fastpath+0x23/0x9a
RIP: 0033:0x452ac9
RSP: 002b:00007f40b5017c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f40b5018700 RCX: 0000000000452ac9
RDX: 0000000000000000 RSI: 0000000020004000 RDI: 0000000000000013
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000
R13: 0000000000a2f7ef R14: 00007f40b50189c0 R15: 0000000000000000
BUG: scheduling while atomic: syz-executor3/9287/0x00000002
2 locks held by syz-executor3/9287:
 #0:  (&net->xfrm.xfrm_cfg_mutex){+.+.}, at: [<00000000c9cd6449>] xfrm_netlink_rcv+0x60/0x90 net/xfrm/xfrm_user.c:2598
 #1:  (rcu_read_lock){....}, at: [<00000000d6fd3009>] xfrm_state_get_afinfo+0x62/0x280 net/xfrm/xfrm_state.c:2157
Modules linked in: