=============================
WARNING: suspicious RCU usage
6.11.0-rc6-syzkaller-00326-gd1f2d51b711a #0 Not tainted
-----------------------------
net/sched/sch_generic.c:1284 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
3 locks held by kworker/u32:4/82:
 #0: ffff88804a828948 ((wq_completion)bond0){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206
 #1: ffffc90000fcfd80 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207
 #2: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 #2: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #2: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: bond_mii_monitor+0x140/0x2d90 drivers/net/bonding/bond_main.c:2863

stack backtrace:
CPU: 2 UID: 0 PID: 82 Comm: kworker/u32:4 Not tainted 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: bond0 bond_mii_monitor
Call Trace:
 <TASK>
 linkwatch_do_dev+0x11e/0x160 net/core/link_watch.c:175
 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231
WARNING: suspicious RCU usage
include/linux/rtnetlink.h:100 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1

stack backtrace:
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: bond0 bond_mii_monitor
Call Trace:
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:119
 dev_ingress_queue include/linux/rtnetlink.h:100 [inline]
 dev_deactivate_many+0x8ac/0xb20 net/sched/sch_generic.c:1359
 bond_check_dev_link+0x197/0x490 drivers/net/bonding/bond_main.c:799
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
==================================================================
Read of size 8 at addr ffffc900009d7b20 by task kworker/u32:4/82
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
 dev_deactivate_queue+0x17e/0x190 net/sched/sch_generic.c:1284
 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

The buggy address belongs to the virtual mapping at
 [ffffc900009d0000, ffffc900009d9000) created by:
 kernel_clone+0xfd/0x960 kernel/fork.c:2781

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1fe27
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_ZERO), pid 2, tgid 2 (kthreadd), ts 4221965269, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1500
 prep_new_page mm/page_alloc.c:1508 [inline]
 get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3446
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4702
 alloc_pages_mpol_noprof+0x275/0x610 mm/mempolicy.c:2263
 vm_area_alloc_pages mm/vmalloc.c:3587 [inline]
 __vmalloc_area_node mm/vmalloc.c:3656 [inline]
 __vmalloc_node_range_noprof+0x6da/0x14e0 mm/vmalloc.c:3837
 alloc_thread_stack_node kernel/fork.c:313 [inline]
 dup_task_struct kernel/fork.c:1113 [inline]
 copy_process+0x2f3b/0x8de0 kernel/fork.c:2204
 kernel_clone+0xfd/0x960 kernel/fork.c:2781
 kernel_thread+0xc0/0x100 kernel/fork.c:2843
 create_kthread kernel/kthread.c:412 [inline]
 kthreadd+0x4ef/0x7d0 kernel/kthread.c:765
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
page_owner free stack trace missing

Memory state around the buggy address:
 ffffc900009d7a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900009d7a80: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f1 f1 00 f2
>ffffc900009d7b00: f2 f2 00 00 f2 f2 00 00 f2 f2 00 00 00 00 00 f3
                               ^
 ffffc900009d7b80: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900009d7c00: 00 00 f1 f1 f1 f1 00 00 f2 f2 00 00 f3 f3 00 00
==================================================================