Hello, syzbot found the following issue on: HEAD commit: d7691390 Merge tag 'block-5.10-2020-10-24' of git://git.ke.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=161d04b0500000 kernel config: https://syzkaller.appspot.com/x/.config?x=65e86ae741289c65 dashboard link: https://syzkaller.appspot.com/bug?extid=dd74984384afdb86e904 compiler: gcc (GCC) 10.1.0-syz 20200507 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+dd74984384afdb86e904@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ WARNING: CPU: 2 PID: 19299 at include/linux/cpumask.h:137 ttwu_stat include/linux/rcupdate.h:779 [inline] WARNING: CPU: 2 PID: 19299 at include/linux/cpumask.h:137 try_to_wake_up+0xd5e/0x1300 kernel/sched/core.c:2979 Modules linked in: CPU: 2 PID: 19299 Comm: io_wq_manager Not tainted 5.9.0-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:137 [inline] RIP: 0010:cpumask_check include/linux/cpumask.h:144 [inline] RIP: 0010:cpumask_check include/linux/cpumask.h:142 [inline] RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:367 [inline] RIP: 0010:is_cpu_allowed kernel/sched/core.c:1705 [inline] RIP: 0010:select_task_rq kernel/sched/core.c:2370 [inline] RIP: 0010:try_to_wake_up+0xd5e/0x1300 kernel/sched/core.c:2964 Code: 70 02 00 00 65 ff 0d d1 97 b5 7e 4c 8d 75 40 0f 85 da f8 ff ff e8 61 ed b3 ff e9 d0 f8 ff ff 41 bd 01 00 00 00 e9 6e f3 ff ff <0f> 0b e9 2d f6 ff ff 48 8d bd 98 01 00 00 48 b8 00 00 00 00 00 fc RSP: 0018:ffffc900014b7d50 EFLAGS: 00010002 RAX: dffffc0000000000 RBX: 1ffff92000296faf RCX: ffff88805e6e1330 RDX: 1ffff1100bcdc265 RSI: ffffffff83b4fecb RDI: 0000000000000006 RBP: ffff88805e6e0fc0 R08: 0000000000000008 R09: ffffffff8cecd34f R10: 0000000000000040 R11: 0000000000000000 R12: 0000000000000206 R13: ffff88805e6e17f0 R14: ffff88805e6e1000 R15: ffff88805e6e1328 FS: 0000000000000000(0000) GS:ffff88802cc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000b60004 CR3: 0000000067ffb000 CR4: 0000000000350ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: create_io_worker+0x590/0x8d0 fs/io-wq.c:716 io_wq_manager+0x16b/0xb80 fs/io-wq.c:781 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
