=====================================================
BUG: KMSAN: uninit-value in __flush_smp_call_function_queue+0x343/0x1810 kernel/smp.c:549
 __flush_smp_call_function_queue+0x343/0x1810 kernel/smp.c:549
 generic_smp_call_function_single_interrupt+0x1c/0x30 kernel/smp.c:477
 __sysvec_call_function_single+0x48/0x350 arch/x86/kernel/smp.c:272
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:267 [inline]
 sysvec_call_function_single+0x7c/0x90 arch/x86/kernel/smp.c:267
 asm_sysvec_call_function_single+0x1f/0x30 arch/x86/include/asm/idtentry.h:704
 kmsan_get_shadow_origin_ptr+0x8/0xb0 mm/kmsan/shadow.c:83
 get_shadow_origin_ptr mm/kmsan/instrumentation.c:38 [inline]
 __msan_metadata_ptr_for_load_8+0x24/0x40 mm/kmsan/instrumentation.c:94
 last_frame arch/x86/kernel/unwind_frame.c:82 [inline]
 is_last_frame arch/x86/kernel/unwind_frame.c:87 [inline]
 is_last_task_frame+0x44/0x370 arch/x86/kernel/unwind_frame.c:156
 unwind_next_frame+0x60/0x350 arch/x86/kernel/unwind_frame.c:276
 __unwind_start+0x3bf/0x530 arch/x86/kernel/unwind_frame.c:417
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xfc/0x280 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0xc2/0x100 kernel/stacktrace.c:122
 kmsan_save_stack_with_flags mm/kmsan/core.c:73 [inline]
 kmsan_internal_poison_memory+0x4a/0x90 mm/kmsan/core.c:57
 kmsan_slab_free+0xce/0x140 mm/kmsan/hooks.c:87
 slab_free_hook mm/slub.c:2615 [inline]
 slab_free mm/slub.c:6251 [inline]
 kfree+0x315/0x1100 mm/slub.c:6566
 skb_kfree_head net/core/skbuff.c:1075 [inline]
 skb_free_head+0xaf/0x640 net/core/skbuff.c:1087
 pskb_expand_head+0x6aa/0x1a40 net/core/skbuff.c:2335
 netlink_trim+0x3a3/0x450 net/netlink/af_netlink.c:1299
 netlink_broadcast_filtered+0x80/0x2930 net/netlink/af_netlink.c:1517
 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
 nlmsg_multicast include/net/netlink.h:1184 [inline]
 nlmsg_notify+0x15b/0x2f0 net/netlink/af_netlink.c:2598
 rtnl_notify net/core/rtnetlink.c:964 [inline]
 rtmsg_ifinfo_send net/core/rtnetlink.c:4474 [inline]
 rtmsg_ifinfo_event net/core/rtnetlink.c:4490 [inline]
 rtmsg_ifinfo+0x1aa/0x250 net/core/rtnetlink.c:4496
 __dev_notify_flags+0x98/0x890 net/core/dev.c:9793
 __dev_set_promiscuity+0x325/0xa50 net/core/dev.c:9636
 netif_set_promiscuity+0x65/0x170 net/core/dev.c:9645
 dev_set_promiscuity+0x187/0x330 net/core/dev_api.c:288
 hsr_del_port+0x495/0x6f0 net/hsr/hsr_slave.c:244
 hsr_del_ports+0xdd/0x200 net/hsr/hsr_device.c:475
 hsr_dellink+0x99/0xe0 net/hsr/hsr_netlink.c:142
 default_device_exit_batch+0xe7a/0x1120 net/core/dev.c:13071
 ops_exit_list net/core/net_namespace.c:205 [inline]
 ops_undo_list+0x7e0/0xb80 net/core/net_namespace.c:252
 cleanup_net+0xc24/0x1680 net/core/net_namespace.c:702
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb65/0x1e40 kernel/workqueue.c:3397
 worker_thread+0xee4/0x1590 kernel/workqueue.c:3478
 kthread+0x53a/0x5f0 kernel/kthread.c:436
 ret_from_fork+0x20f/0x8d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Local variable cycles.i created at:
 clockevent_set_next_coupled kernel/time/clockevents.c:309 [inline]
 clockevents_program_event+0x178/0x830 kernel/time/clockevents.c:360
 tick_program_event+0xfb/0x190 kernel/time/tick-oneshot.c:48

CPU: 1 UID: 0 PID: 5917 Comm: kworker/u8:17 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: netns cleanup_net
=====================================================