kernel oops in pick_next_task_fair in 6.8.1-1002-realtime kernel
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
ubuntu-realtime |
New
|
Medium
|
Unassigned |
Bug Description
Ubuntu Noble, Real Time kernel:
cking@noble-
Linux noble-amd64-efi 6.8.1-1002-realtime #2-Ubuntu SMP PREEMPT_RT Tue May 21 21:13:36 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
How to reproduce issue:
git clone https:/
cd stress-ng
make clean; make -j 8
sudo ./stress-ng --seq 16 -t 20 --metrics --vmstat 5 -x apparmor,prio-inv --progress --pathological
Note that this oops'd while executing the schedpolicy stressor, but just running this stressor by itself doesn't seem to trigger the oops per se, so it may be something to do with stressors being run prior to the schedpolicy stressor.
...
stress-ng: info: [8315] starting schedpolicy, 224 of 330 (67.88%), 16 instances, finish at 13:11:48 2024-06-06
stress-ng: info: [8318] vmstat: 16 0 70076 3422692 158820 167256 4 0 17 0 65858 266843 34 57 9 0 0
[ 4943.415061] BUG: kernel NULL pointer dereference, address: 00000000000000a0
[ 4943.415069] #PF: supervisor read access in kernel mode
[ 4943.415071] #PF: error_code(0x0000) - not-present page
[ 4943.415072] PGD 0 P4D 0
[ 4943.415075] Oops: 0000 [#1] PREEMPT_RT SMP PTI
[ 4943.415079] CPU: 4 PID: 690936 Comm: kworker/u33:4 Not tainted 6.8.1-1002-realtime #2-Ubuntu
[ 4943.415083] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 2024.02-2 03/11/2024
[ 4943.415085] Workqueue: 0x0 (ttm)
[ 4943.415158] RIP: 0010:pick_
[ 4943.415165] Code: 93 00 00 00 49 81 bd b0 02 00 00 00 d3 8e bd 75 62 4d 89 fe eb 27 4c 89 f7 e8 3b bf ff ff 84 c0 75 41 4c 89 f7 e8 8f 3e ff ff <4c> 8b b0 a0 00 00 00 48 89 c3 4d 85 f6 0f 84 fe 00 00 00 49 8b 46
[ 4943.415168] RSP: 0000:ffffa2ccc8
[ 4943.415172] RAX: 0000000000000000 RBX: ffffa2ccc8fcfe10 RCX: 0000000000000000
[ 4943.415173] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 4943.415175] RBP: ffffa2ccc8fcfd78 R08: 0000000000000000 R09: 0000000000000000
[ 4943.415177] R10: 0000000000000000 R11: 0000000000000000 R12: ffff9395fbc35300
[ 4943.415178] R13: ffff93958e0c5200 R14: ffff9395fbc35400 R15: ffff9395fbc35400
[ 4943.415181] FS: 000000000000000
[ 4943.415183] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4943.415185] CR2: 00000000000000a0 CR3: 000000014b696006 CR4: 0000000000370ef0
[ 4943.415192] Call Trace:
[ 4943.415194] <TASK>
[ 4943.415196] ? show_regs+0x6d/0x80
[ 4943.415201] ? __die+0x24/0x80
[ 4943.415204] ? page_fault_
[ 4943.415210] ? do_user_
[ 4943.415214] ? exc_page_
[ 4943.415218] ? asm_exc_
[ 4943.415225] ? pick_next_
[ 4943.415230] ? pick_next_
[ 4943.415235] pick_next_
[ 4943.415242] __schedule+
[ 4943.415246] ? trace_preempt_
[ 4943.415250] ? process_
[ 4943.415256] schedule+0x38/0x120
[ 4943.415260] worker_
[ 4943.415265] ? __pfx_worker_
[ 4943.415269] kthread+0xfe/0x130
[ 4943.415273] ? __pfx_kthread+
[ 4943.415276] ret_from_
[ 4943.415280] ? __pfx_kthread+
[ 4943.415283] ret_from_
[ 4943.415290] </TASK>
[ 4943.415291] Modules linked in: snd_seq_dummy tls cuse uhid snd_seq snd_seq_device userio hci_vhci bluetooth ecdh_generic ecc vfio_iommu_type1 vfio iommufd nvram vhost_vsock vmw_vsock_
[ 4943.415418] des3_ede_x86_64 des_generic libdes authenc aegis128 aegis128_aesni algif_aead af_alg qrtr cfg80211 binfmt_misc intel_rapl_msr intel_rapl_common intel_pmc_core intel_vsec pmt_telemetry pmt_class nls_iso8859_1 kvm_intel kvm irqbypass rapl snd_hda_
[ 4943.415498] CR2: 00000000000000a0
[ 4943.415501] ---[ end trace 0000000000000000 ]---
[ 4943.450926] hrtimer: interrupt took 5190862 ns
Changed in linux (Ubuntu): | |
importance: | Undecided → Medium |
affects: | linux (Ubuntu) → ubuntu-realtime |
Thanks for this one too, Colin. I'll see if I can reproduce this as well. Can you provide more information on the system where you got this kernel oops? Was it a VM? Can you give the VM's configuration?