Previously unseen warning with 5.14.4 in take_other_rq_tasks()
I just found the following in the kernel log of my Zen2 Thinkpad while running ffmpeg:
Sep 14 17:05:50 hho kernel: pds: task_sched_prio_normal() delta 64
Sep 14 17:05:50 hho kernel: WARNING: CPU: 1 PID: 10187 at kernel/sched/pds.h:21 take_other_rq_tasks+0x49e/0x510
Sep 14 17:05:50 hho kernel: Modules linked in: auth_rpcgss nfsv4 lz4 lz4_compress lz4_decompress nfs lockd grace sunrpc tcp_bbr2 sch_fq_codel intel_rapl_msr intel_rapl_common iosf_mbi iwlmvm amdgpu snd_ctl_led lm92 mac80211 snd_hda_codec_realtek snd_hda_codec_generic libarc4 drivetemp drm_ttm_helper wmi_bmof ttm iommu_v2 gpu_sched snd_hda_codec_hdmi i2c_algo_bit drm_kms_helper btusb btrtl cec uvcvideo btbcm snd_hda_intel btintel videobuf2_vmalloc snd_intel_dspcfg videobuf2_memops drm iwlwifi edac_mce_amd videobuf2_v4l2 bluetooth snd_hda_codec crct10dif_pclmul videobuf2_common snd_hwdep crc32_pclmul crc32c_intel syscopyarea snd_hda_core videodev ghash_clmulni_intel sysfillrect sysimgblt ecdh_generic rapl serio_raw mc ecc snd_pcm k10temp fb_sys_fops thinkpad_acpi snd_timer snd_rn_pci_acp3x cfg80211 snd snd_pci_acp3x i2c_piix4 soundcore ccp platform_profile ledtrig_audio r8169 ipmi_devintf ipmi_msghandler realtek ucsi_acpi typec_ucsi roles typec wmi rfkill battery ac video i2c_scmi pinctrl_amd button
Sep 14 17:05:50 hho kernel: CPU: 1 PID: 10187 Comm: ffmpeg Not tainted 5.14.4 #1
Sep 14 17:05:50 hho kernel: Hardware name: LENOVO 20U50001GE/20U50001GE, BIOS R19ET32W (1.16 ) 01/26/2021
Sep 14 17:05:50 hho kernel: RIP: 0010:take_other_rq_tasks+0x49e/0x510
Sep 14 17:05:50 hho kernel: Code: af 01 00 b8 3f 00 00 00 0f 85 3f ff ff ff 48 c7 c7 a0 9a 31 82 89 44 24 34 48 89 4c 24 08 c6 05 3a df af 01 01 e8 c9 0d 8f 00 <0f> 0b 49 8b bf 58 0c 00 00 8b 44 24 34 48 8b 4c 24 08 e9 0c ff ff
Sep 14 17:05:50 hho kernel: RSP: 0018:ffffc90002c1fb90 EFLAGS: 00010086
Sep 14 17:05:50 hho kernel: RAX: 0000000000000026 RBX: ffff8881067ab300 RCX: 0000000000000027
Sep 14 17:05:50 hho kernel: RDX: ffff8883ff4576a8 RSI: 0000000000000001 RDI: ffff8883ff4576a0
Sep 14 17:05:50 hho kernel: RBP: ffff8883ff6ab040 R08: ffff88840f1fbfe8 R09: 00000000fffeffff
Sep 14 17:05:50 hho kernel: R10: ffff8883fec80000 R11: ffff8883fec80000 R12: 0000000000000001
Sep 14 17:05:50 hho kernel: R13: ffff888100872640 R14: 0000000000000001 R15: ffff8883ff46b040
Sep 14 17:05:50 hho kernel: FS: 00007fd2977fe640(0000) GS:ffff8883ff440000(0000) knlGS:0000000000000000
Sep 14 17:05:50 hho kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Sep 14 17:05:50 hho kernel: CR2: 00007f19431fd000 CR3: 00000001e3bfc000 CR4: 0000000000350ee0
Sep 14 17:05:50 hho kernel: Call Trace:
Sep 14 17:05:50 hho kernel: __schedule+0x62c/0xa20
Sep 14 17:05:50 hho kernel: ? generic_reg_get+0x1d/0x30 [amdgpu]
Sep 14 17:05:50 hho kernel: schedule+0x44/0xa0
Sep 14 17:05:50 hho kernel: futex_wait_queue_me+0x98/0xf0
Sep 14 17:05:50 hho kernel: futex_wait+0xd8/0x200
Sep 14 17:05:50 hho kernel: ? drm_handle_vblank+0x229/0x330 [drm]
Sep 14 17:05:50 hho kernel: ? amdgpu_dm_crtc_handle_crc_irq+0x4a/0xd0 [amdgpu]
Sep 14 17:05:50 hho kernel: do_futex+0xeb/0x960
Sep 14 17:05:50 hho kernel: ? sugov_update_single_freq+0x13b/0x270
Sep 14 17:05:50 hho kernel: ? update_process_times+0xb1/0xc0
Sep 14 17:05:50 hho kernel: ? timerqueue_add+0x66/0xb0
Sep 14 17:05:50 hho kernel: ? enqueue_hrtimer+0x32/0x70
Sep 14 17:05:50 hho kernel: ? __hrtimer_run_queues+0x144/0x230
Sep 14 17:05:50 hho kernel: ? ktime_get+0x35/0xa0
Sep 14 17:05:50 hho kernel: __x64_sys_futex+0x63/0x1a0
Sep 14 17:05:50 hho kernel: do_syscall_64+0x35/0x80
Sep 14 17:05:50 hho kernel: entry_SYSCALL_64_after_hwframe+0x44/0xae
Sep 14 17:05:50 hho kernel: RIP: 0033:0x7fd2e9a216c2
Sep 14 17:05:50 hho kernel: Code: 24 08 e8 61 ca ff ff 89 c5 41 b9 ff ff ff ff 45 31 c0 4c 8b 54 24 18 8b 74 24 08 44 89 e2 b8 ca 00 00 00 48 8b 7c 24 10 0f 05 <89> ef 48 89 44 24 08 e8 b2 ca ff ff 48 8b 44 24 08 e9 61 ff ff ff
Sep 14 17:05:50 hho kernel: RSP: 002b:00007fd2977f5080 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
Sep 14 17:05:50 hho kernel: RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd2e9a216c2
Sep 14 17:05:50 hho kernel: RDX: 0000000000000000 RSI: 0000000000000189 RDI: 0000564f5dacbc40
Sep 14 17:05:50 hho kernel: RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000ffffffff
Sep 14 17:05:50 hho kernel: R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
Sep 14 17:05:50 hho kernel: R13: 0000564f5dacbbf0 R14: 0000564f5dacbc40 R15: 0000000000000000
Sep 14 17:05:50 hho kernel: ---[ end trace f0821126512f2de6 ]---
This is with PDS for 5.14. While ffmpeg was running the screen went into suspend (due to no input activity), maybe that's why amdgu is in there. This is the first tme this (or anything PDS-related) happened. System is completely stable & fast otherwise, so not sure what happened here.