Hi Colin, I've consistently reproduced this issue in QEMU VMs on arm64 realtime (6.8.1.1002-realtime). However, it also occurs with the generic kernel (6.8.0-35-generic) on arm64. I couldn't get it to happen with amd64.
Here's the dmesg output on 6.8.0-35-generic after the modprobe gets stuck:
Hi Colin, I've consistently reproduced this issue in QEMU VMs on arm64 realtime (6.8.1. 1002-realtime) . However, it also occurs with the generic kernel (6.8.0-35-generic) on arm64. I couldn't get it to happen with amd64.
Here's the dmesg output on 6.8.0-35-generic after the modprobe gets stuck:
[ 303.168453] input: Speakup as /devices/ virtual/ input/input1 kernel/ hung_task_ timeout_ secs" disables this message. to+0xbc/ 0xf0 0x2a8/0x7b0 preempt_ disabled+ 0x30/0x68 lock.constprop. 0+0x31c/ 0x5d0 lock_slowpath+ 0x20/0x48 0x8c/0xc0 0x3c/0x110 [speakup] init+0x24/ 0xff8 [speakup_apollo] initcall+ 0x64/0x3b8 module+ 0xa4/0x280 0x7b8/0x8f0 from_file+ 0x98/0x118 init_module+ 0x1a4/0x2c8 sys_finit_ module+ 0x70/0xf8 syscall+ 0x7c/0x128 common. constprop. 0+0x4c/ 0x140 svc+0x28/ 0x58 sync_handler+ 0x148/0x158 sync+0x1b0/ 0x1b8
[ 303.174246] initialized device: /dev/synth, node (MAJOR 10, MINOR 122)
[ 303.176539] speakup 3.1.6: initialized
[ 303.176600] synth name on entry is: (null)
[ 303.187469] synth probe
[ 492.396049] INFO: task modprobe:1042 blocked for more than 122 seconds.
[ 492.397557] Not tainted 6.8.0-35-generic #35-Ubuntu
[ 492.398493] "echo 0 > /proc/sys/
[ 492.399616] task:modprobe state:D stack:0 pid:1042 tgid:1042 ppid:1041 flags:0x00000004
[ 492.401357] Call trace:
[ 492.401789] __switch_
[ 492.403196] __schedule+
[ 492.403312] schedule+0x40/0x168
[ 492.403363] schedule_
[ 492.403408] __mutex_
[ 492.403454] __mutex_
[ 492.403502] mutex_lock+
[ 492.403541] synth_add+
[ 492.404115] synth_apollo_
[ 492.404213] do_one_
[ 492.404260] do_init_
[ 492.404316] load_module+
[ 492.404364] init_module_
[ 492.404412] idempotent_
[ 492.404459] __arm64_
[ 492.404511] invoke_
[ 492.404563] el0_svc_
[ 492.404763] do_el0_
[ 492.404823] el0_svc+0x44/0x1a0
[ 492.404874] el0t_64_
[ 492.404926] el0t_64_
We'll continue investigating this.