[BUG] wait_task_inactive() WARN_ON() in __kthread_bind_mask()

[Paul E. McKenney]

Hello!

I just now saw this in SRCU-P rcutorture testing.  It might well be a
one-off, but I thought I should pass it along in case someone else is
seeing similar things.

I don't immediately see how this would be related, but who knows?

https://lore.kernel.org/lkml/20230524035339.25185-1-qiang.zhang1211@xxxxxxxxx/

Thoughts?

							Thanx, Paul

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[ 1726.040567] ------------[ cut here ]------------
[ 1726.040569] WARNING: CPU: 3 PID: 2016 at kernel/kthread.c:515 __kthread_bind_mask+0x18/0x60
[ 1726.040581] Modules linked in:
[ 1726.040584] CPU: 3 PID: 2016 Comm: kworker/7:3 Not tainted 6.4.0-rc1-00072-g99f9f93c0bce #5209
[ 1726.040588] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
[ 1726.040594] RIP: 0010:__kthread_bind_mask+0x18/0x60
[ 1726.040598] Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 55 41 54 55 48 89 f5 89 d6 53 48 89 fb e8 8d 5a 01 00 48 85 c0 75 0d <0f> 0b 5b 5d 41 5c 41 5d c3 cc cc cc cc 4c 8d a3 00 09 00 00 4c 89
[ 1726.040601] RSP: 0000:ffff97c7c1ecfe78 EFLAGS: 00010246
[ 1726.040604] RAX: 0000000000000000 RBX: ffff90ce82918000 RCX: 0000000000000000
[ 1726.040606] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff90ce82918000
[ 1726.040607] RBP: ffff90ce81047248 R08: 0000000000000001 R09: ffffffff9cab5d97
[ 1726.040609] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004
[ 1726.040610] R13: ffff90ce9f5ee460 R14: ffff97c7c1ecfea0 R15: ffff90ce812ef840
[ 1726.040614] FS:  0000000000000000(0000) GS:ffff90ce9f4c0000(0000) knlGS:0000000000000000
[ 1726.040616] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1726.040618] CR2: 0000000000000000 CR3: 0000000014648000 CR4: 00000000000006e0
[ 1726.040619] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1726.040621] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1726.040622] Call Trace:
[ 1726.040624]  <TASK>
[ 1726.040630]  create_worker+0xf1/0x220
[ 1726.040637]  worker_thread+0x2e4/0x3b0
[ 1726.040641]  ? __pfx_worker_thread+0x10/0x10
[ 1726.040643]  kthread+0xe6/0x120
[ 1726.040648]  ? __pfx_kthread+0x10/0x10
[ 1726.040651]  ret_from_fork+0x2c/0x50
[ 1726.040658]  </TASK>
[ 1726.040659] irq event stamp: 34
[ 1726.040661] hardirqs last  enabled at (33): [<ffffffff9da014ea>] asm_sysvec_call_function_single+0x1a/0x20
[ 1726.040668] hardirqs last disabled at (34): [<ffffffff9d95cead>] __schedule+0x67d/0xd20
[ 1726.040675] softirqs last  enabled at (0): [<ffffffff9ca82da8>] copy_process+0xb98/0x1f10
[ 1726.040681] softirqs last disabled at (0): [<0000000000000000>] 0x0
[ 1726.040685] ---[ end trace 0000000000000000 ]---