Hello, syzbot found the following issue on: HEAD commit: 449dc8c9 Merge tag 'for-v5.9' of git://git.kernel.org/pub/.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing console output: https://syzkaller.appspot.com/x/log.txt?x=16581652900000 kernel config: https://syzkaller.appspot.com/x/.config?x=6ef84fa8ee48e528 dashboard link: https://syzkaller.appspot.com/bug?extid=c2c3302f9c601a4b1be2 compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16e8de34900000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1244eb62900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c2c3302f9c601a4b1be2@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ do not call blocking ops when !TASK_RUNNING; state=1 set at [<00000000370c7c68>] prepare_to_wait+0xb1/0x2a0 kernel/sched/wait.c:247 WARNING: CPU: 1 PID: 340 at kernel/sched/core.c:7253 __might_sleep+0x135/0x190 kernel/sched/core.c:7253 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 340 Comm: syz-executor677 Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xf6/0x16e lib/dump_stack.c:118 panic+0x2aa/0x6e1 kernel/panic.c:231 __warn.cold+0x20/0x50 kernel/panic.c:600 report_bug+0x1bd/0x210 lib/bug.c:198 handle_bug+0x41/0x80 arch/x86/kernel/traps.c:234 exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536 RIP: 0010:__might_sleep+0x135/0x190 kernel/sched/core.c:7253 Code: 65 48 8b 1c 25 40 ef 01 00 48 8d 7b 10 48 89 fe 48 c1 ee 03 80 3c 06 00 75 2b 48 8b 73 10 48 c7 c7 e0 9e 06 86 e8 ed 12 f6 ff <0f> 0b e9 46 ff ff ff e8 1f b2 4b 00 e9 29 ff ff ff e8 15 b2 4b 00 RSP: 0018:ffff8881cdb77a28 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff8881c6458000 RCX: 0000000000000000 RDX: ffff8881c6458000 RSI: ffffffff8129ec93 RDI: ffffed1039b6ef37 RBP: ffffffff86fdade2 R08: 0000000000000001 R09: ffff8881db32f54f R10: 0000000000000000 R11: 0000000030343354 R12: 00000000000001f2 R13: 0000000000000000 R14: 0000000000000068 R15: ffffffff83c1b1aa slab_pre_alloc_hook.constprop.0+0xea/0x200 mm/slab.h:498 slab_alloc_node mm/slub.c:2816 [inline] slab_alloc mm/slub.c:2900 [inline] kmem_cache_alloc_trace+0x46/0x220 mm/slub.c:2917 kmalloc include/linux/slab.h:554 [inline] dummy_urb_enqueue+0x7a/0x880 drivers/usb/gadget/udc/dummy_hcd.c:1251 usb_hcd_submit_urb+0x2b2/0x22d0 drivers/usb/core/hcd.c:1547 usb_submit_urb+0xb4e/0x13e0 drivers/usb/core/urb.c:570 yurex_write+0x3ea/0x820 drivers/usb/misc/yurex.c:495 vfs_write+0x2b0/0x730 fs/read_write.c:576 ksys_write+0x12d/0x250 fs/read_write.c:631 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x444809 Code: e8 bc af 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 0f 83 9b d7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc4c2b1358 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000444809 RDX: 00000000000000cb RSI: 0000000020000300 RDI: 0000000000000004 RBP: 00000000006cf018 R08: 000000000000000f R09: 00000000004002e0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402430 R13: 00000000004024c0 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds.. --- 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. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches