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BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 4218, name: syz-executor370
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
2 locks held by syz-executor370/4218:
 #0: ffff800017b8e848 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffff800017b8e848 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e8/0xd94 net/core/rtnetlink.c:6094
 #1: ffff0000d312a908 (&sch->q.lock){+...}-{2:2}, at: sch_tree_lock+0x120/0x1d4
Preemption disabled at:
[<ffff8000106bed08>] sch_tree_lock+0x120/0x1d4
CPU: 1 PID: 4218 Comm: syz-executor370 Not tainted 6.1.36-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 __might_resched+0x37c/0x4d8 kernel/sched/core.c:9941
 __might_sleep+0x90/0xe4 kernel/sched/core.c:9870
 might_alloc include/linux/sched/mm.h:274 [inline]
 slab_pre_alloc_hook mm/slab.h:710 [inline]
 slab_alloc_node mm/slub.c:3318 [inline]
 __kmem_cache_alloc_node+0x74/0x388 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc_node+0xcc/0x1d0 mm/slab_common.c:962
 kmalloc_node include/linux/slab.h:579 [inline]
 kvmalloc_node+0x84/0x1e4 mm/util.c:581
 kvmalloc include/linux/slab.h:706 [inline]
 get_dist_table+0xa0/0x354 net/sched/sch_netem.c:788
 netem_change+0x7a4/0x1900 net/sched/sch_netem.c:992
 netem_init+0x54/0xb8 net/sched/sch_netem.c:1072
 qdisc_create+0x70c/0xe64 net/sched/sch_api.c:1314
 tc_modify_qdisc+0x9f0/0x1840
 rtnetlink_rcv_msg+0x72c/0xd94 net/core/rtnetlink.c:6097
 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2524
 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6115
 netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
 netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1354
 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1902
 sock_sendmsg_nosec net/socket.c:716 [inline]
 sock_sendmsg net/socket.c:736 [inline]
 ____sys_sendmsg+0x558/0x844 net/socket.c:2482
 ___sys_sendmsg net/socket.c:2536 [inline]
 __sys_sendmsg+0x26c/0x33c net/socket.c:2565
 __do_sys_sendmsg net/socket.c:2574 [inline]
 __se_sys_sendmsg net/socket.c:2572 [inline]
 __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2572
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

============================================
WARNING: possible recursive locking detected
6.1.36-syzkaller #0 Tainted: G        W         
--------------------------------------------
syz-executor370/4218 is trying to acquire lock:
ffff0000d312a908 (&sch->q.lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline]
ffff0000d312a908 (&sch->q.lock){+...}-{2:2}, at: get_dist_table+0x240/0x354 net/sched/sch_netem.c:798

but task is already holding lock:
ffff0000d312a908 (&sch->q.lock){+...}-{2:2}, at: sch_tree_lock+0x120/0x1d4

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&sch->q.lock);
  lock(&sch->q.lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by syz-executor370/4218:
 #0: ffff800017b8e848 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffff800017b8e848 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e8/0xd94 net/core/rtnetlink.c:6094
 #1: ffff0000d312a908 (&sch->q.lock){+...}-{2:2}, at: sch_tree_lock+0x120/0x1d4

stack backtrace:
CPU: 1 PID: 4218 Comm: syz-executor370 Tainted: G        W          6.1.36-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 __lock_acquire+0x6310/0x764c kernel/locking/lockdep.c:5056
 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5669
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
 _raw_spin_lock_bh+0x54/0x6c kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:355 [inline]
 get_dist_table+0x240/0x354 net/sched/sch_netem.c:798
 netem_change+0x7a4/0x1900 net/sched/sch_netem.c:992
 netem_init+0x54/0xb8 net/sched/sch_netem.c:1072
 qdisc_create+0x70c/0xe64 net/sched/sch_api.c:1314
 tc_modify_qdisc+0x9f0/0x1840
 rtnetlink_rcv_msg+0x72c/0xd94 net/core/rtnetlink.c:6097
 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2524
 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6115
 netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
 netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1354
 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1902
 sock_sendmsg_nosec net/socket.c:716 [inline]
 sock_sendmsg net/socket.c:736 [inline]
 ____sys_sendmsg+0x558/0x844 net/socket.c:2482
 ___sys_sendmsg net/socket.c:2536 [inline]
 __sys_sendmsg+0x26c/0x33c net/socket.c:2565
 __do_sys_sendmsg net/socket.c:2574 [inline]
 __se_sys_sendmsg net/socket.c:2572 [inline]
 __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2572
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581