============================= WARNING: suspicious RCU usage 5.19.0-rc4-next-20220628-syzkaller #0 Not tainted ----------------------------- lib/maple_tree.c:844 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 5 locks held by syz-executor321/3708: #0: ffff88807eeba460 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x127/0x250 fs/read_write.c:644 #1: ffff88807c02dc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x28c/0x610 fs/kernfs/file.c:281 #2: ffff888145276e88 (kn->active#106){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b0/0x610 fs/kernfs/file.c:282 #3: ffffffff8bee2de8 (ksm_thread_mutex){+.+.}-{3:3}, at: run_store+0xd1/0xae0 mm/ksm.c:2923 #4: ffff888077d1d858 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline] #4: ffff888077d1d858 (&mm->mmap_lock#2){++++}-{3:3}, at: unmerge_and_remove_all_rmap_items mm/ksm.c:989 [inline] #4: ffff888077d1d858 (&mm->mmap_lock#2){++++}-{3:3}, at: run_store+0x2a0/0xae0 mm/ksm.c:2929 stack backtrace: CPU: 1 PID: 3708 Comm: syz-executor321 Not tainted 5.19.0-rc4-next-20220628-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 mas_root lib/maple_tree.c:844 [inline] mas_start lib/maple_tree.c:1331 [inline] mas_state_walk lib/maple_tree.c:3812 [inline] mas_walk+0x45e/0x670 lib/maple_tree.c:4997 mas_find+0x346/0xce0 lib/maple_tree.c:5942 vma_find include/linux/mm.h:664 [inline] vma_next include/linux/mm.h:673 [inline] unmerge_and_remove_all_rmap_items mm/ksm.c:990 [inline] run_store+0x2e3/0xae0 mm/ksm.c:2929 kobj_attr_store+0x50/0x80 lib/kobject.c:824 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:290 call_write_iter include/linux/fs.h:2188 [inline] new_sync_write+0x315/0x4d0 fs/read_write.c:504 vfs_write+0x7c0/0xac0 fs/read_write.c:591 ksys_write+0x127/0x250 fs/read_write.c:644 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7f5ee7610e49 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffad53be78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00007f5ee7610e49 RDX: 0000000000000002 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000cd1a R13: 00007fffad53be8c R14: 00007fffad53bea0 R15: 00007fffad53be90