This issue is very closely related to https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1871143
I have a microcontroller plugged into a USB port, doing CDC-ACM. I have either Arduino or Cutecom open with a serial terminal to the device. After some idle time the microcontroller will go into sleep mode and therefore usb will stop working. On previous versions of Ubuntu the serial port will close and the Arduino or Cutecom terminal will be notified and closed too. On Ubuntu 20.04 this does not happen, and the UI will lock up. After some time the entire Gnome session will lock up and I need to force power cycle my computer.
I have kept dmesg tailing in a terminal when this happens and I see the following log:
[ +0.235966] usb 2-2: new full-speed USB device number 9 using xhci_hcd
[ +0.148705] usb 2-2: config 1 interface 1 altsetting 0 endpoint 0x1 has invalid maxpacket 128, setting to 64
[ +0.000003] usb 2-2: config 1 interface 1 altsetting 0 endpoint 0x81 has invalid maxpacket 128, setting to 64
[ +0.000541] usb 2-2: New USB device found, idVendor=0483, idProduct=5740, bcdDevice= 2.00
[ +0.000001] usb 2-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ +0.000002] usb 2-2: Product: Foxtrackr
[ +0.000001] usb 2-2: Manufacturer: IngeniousThings
[ +0.000001] usb 2-2: SerialNumber: 024737453533
[ +0.035228] cdc_acm 2-2:1.0: ttyACM0: USB ACM device
[ +0.000511] usbcore: registered new interface driver cdc_acm
[ +0.000001] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
[Aug30 17:48] D T: urb 12 failed submission with -22
[ +0.000014] BUG: unable to handle page fault for address: 000000020a831230
[ +0.000003] #PF: supervisor read access in kernel mode
[ +0.000003] #PF: error_code(0x0000) - not-present page
[ +0.000002] PGD 0 P4D 0
[ +0.000006] Oops: 0000 [#1] SMP PTI
[ +0.000005] CPU: 0 PID: 593 Comm: kworker/0:4 Not tainted 5.4.0-42-generic #46-Ubuntu
[ +0.000002] Hardware name: Dell Inc. XPS13 9333/0GFTRT, BIOS A08 08/31/2015
[ +0.000010] Workqueue: events acm_softint [cdc_acm]
[ +0.000008] RIP: 0010:usb_submit_urb+0x22/0x5e0
[ +0.000005] Code: 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 18 89 75 d0 48 85 ff 0f 84 ec 03 00 00 <48> 83 bf b0 00 00 00 00 49 89 fc 0f 84 db 03 00 00 48 83 7f 08 00
[ +0.000003] RSP: 0018:ffffb49ec0347dc0 EFLAGS: 00010202
[ +0.000004] RAX: 0000000000000000 RBX: ffff940aa7a87020 RCX: 0000000000000000
[ +0.000002] RDX: 0000000000000c00 RSI: 0000000000000c00 RDI: 000000020a831180
[ +0.000003] RBP: ffffb49ec0347e00 R08: ffff940ad76178c8 R09: ffffffff94bab5e0
[ +0.000002] R10: ffffffff94b941a8 R11: ffffb49ec0347b58 R12: ffff940aa7a877a0
[ +0.000003] R13: 000000000000000e R14: ffff940aa7a87020 R15: ffff940ace929780
[ +0.000003] FS: 0000000000000000(0000) GS:ffff940ad7600000(0000) knlGS:0000000000000000
[ +0.000003] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ +0.000002] CR2: 000000020a831230 CR3: 000000013f40a002 CR4: 00000000001606f0
[ +0.000003] Call Trace:
[ +0.000009] acm_submit_read_urb+0x3f/0x70 [cdc_acm]
[ +0.000006] acm_softint+0x68/0xe0 [cdc_acm]
[ +0.000007] process_one_work+0x1eb/0x3b0
[ +0.000005] worker_thread+0x4d/0x400
[ +0.000005] kthread+0x104/0x140
[ +0.000005] ? process_one_work+0x3b0/0x3b0
[ +0.000004] ? kthread_park+0x90/0x90
[ +0.000007] ret_from_fork+0x35/0x40
[ +0.000003] Modules linked in: cdc_acm rfcomm xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo xt_addrtype iptable_filter iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c bpfilter br_netfilter bridge stp llc ccm aufs cmac algif_hash algif_skcipher af_alg overlay bnep snd_hda_codec_hdmi binfmt_misc nls_iso8859_1 intel_rapl_msr mei_hdcp intel_rapl_common snd_hda_codec_realtek x86_pkg_temp_thermal intel_powerclamp snd_hda_codec_generic coretemp snd_hda_intel kvm_intel snd_intel_dspcfg snd_hda_codec snd_hda_core snd_hwdep kvm snd_pcm snd_seq_midi snd_seq_midi_event crct10dif_pclmul ghash_clmulni_intel dell_laptop ledtrig_audio snd_rawmidi dell_smm_hwmon i915 btusb aesni_intel btrtl crypto_simd btbcm btintel cryptd glue_helper intel_cstate bluetooth intel_rapl_perf snd_seq iwlmvm dell_wmi mac80211 dell_smbios dcdbas sparse_keymap wmi_bmof libarc4 dell_wmi_descriptor serio_raw snd_seq_device snd_timer input_leds joydev iwlwifi ecdh_generic ecc
[ +0.000054] hid_multitouch drm_kms_helper uvcvideo i2c_algo_bit fb_sys_fops snd syscopyarea cfg80211 mei_me soundcore sysfillrect mei sysimgblt acpi_als kfifo_buf industrialio dell_rbtn intel_smartconnect mac_hid sch_fq_codel parport_pc ppdev lp drm parport ip_tables x_tables autofs4 hid_logitech_hidpp hid_logitech_dj uas usb_storage usbhid hid_rmi rmi_core videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common videodev mc hid_generic crc32_pclmul psmouse ahci libahci i2c_i801 lpc_ich wmi video i2c_hid hid
[ +0.000038] CR2: 000000020a831230
[ +0.000004] ---[ end trace 2ced5c1f9722453f ]---
[ +0.000005] RIP: 0010:usb_submit_urb+0x22/0x5e0
[ +0.000004] Code: 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 18 89 75 d0 48 85 ff 0f 84 ec 03 00 00 <48> 83 bf b0 00 00 00 00 49 89 fc 0f 84 db 03 00 00 48 83 7f 08 00
[ +0.000002] RSP: 0018:ffffb49ec0347dc0 EFLAGS: 00010202
[ +0.000003] RAX: 0000000000000000 RBX: ffff940aa7a87020 RCX: 0000000000000000
[ +0.000002] RDX: 0000000000000c00 RSI: 0000000000000c00 RDI: 000000020a831180
[ +0.000002] RBP: ffffb49ec0347e00 R08: ffff940ad76178c8 R09: ffffffff94bab5e0
[ +0.000003] R10: ffffffff94b941a8 R11: ffffb49ec0347b58 R12: ffff940aa7a877a0
[ +0.000002] R13: 000000000000000e R14: ffff940aa7a87020 R15: ffff940ace929780
[ +0.000003] FS: 0000000000000000(0000) GS:ffff940ad7600000(0000) knlGS:0000000000000000
[ +0.000002] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ +0.000003] CR2: 000000020a831230 CR3: 000000013f40a002 CR4: 00000000001606f0
[ +2.234062] ------------[ cut here ]------------
[ +0.000010] WARNING: CPU: 0 PID: 0 at kernel/workqueue.c:1477 __queue_work+0x348/0x3f0
[ +0.000001] Modules linked in: cdc_acm rfcomm xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo xt_addrtype iptable_filter iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c bpfilter br_netfilter bridge stp llc ccm aufs cmac algif_hash algif_skcipher af_alg overlay bnep snd_hda_codec_hdmi binfmt_misc nls_iso8859_1 intel_rapl_msr mei_hdcp intel_rapl_common snd_hda_codec_realtek x86_pkg_temp_thermal intel_powerclamp snd_hda_codec_generic coretemp snd_hda_intel kvm_intel snd_intel_dspcfg snd_hda_codec snd_hda_core snd_hwdep kvm snd_pcm snd_seq_midi snd_seq_midi_event crct10dif_pclmul ghash_clmulni_intel dell_laptop ledtrig_audio snd_rawmidi dell_smm_hwmon i915 btusb aesni_intel btrtl crypto_simd btbcm btintel cryptd glue_helper intel_cstate bluetooth intel_rapl_perf snd_seq iwlmvm dell_wmi mac80211 dell_smbios dcdbas sparse_keymap wmi_bmof libarc4 dell_wmi_descriptor serio_raw snd_seq_device snd_timer input_leds joydev iwlwifi ecdh_generic ecc
[ +0.000035] hid_multitouch drm_kms_helper uvcvideo i2c_algo_bit fb_sys_fops snd syscopyarea cfg80211 mei_me soundcore sysfillrect mei sysimgblt acpi_als kfifo_buf industrialio dell_rbtn intel_smartconnect mac_hid sch_fq_codel parport_pc ppdev lp drm parport ip_tables x_tables autofs4 hid_logitech_hidpp hid_logitech_dj uas usb_storage usbhid hid_rmi rmi_core videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common videodev mc hid_generic crc32_pclmul psmouse ahci libahci i2c_i801 lpc_ich wmi video i2c_hid hid
[ +0.000024] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G D 5.4.0-42-generic #46-Ubuntu
[ +0.000002] Hardware name: Dell Inc. XPS13 9333/0GFTRT, BIOS A08 08/31/2015
[ +0.000003] RIP: 0010:__queue_work+0x348/0x3f0
[ +0.000002] Code: 5a f5 6c a9 00 01 1f 00 75 0f 65 48 8b 3c 25 c0 6b 01 00 f6 47 24 20 75 25 0f 0b 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3 <0f> 0b e9 fd fd ff ff 41 83 cd 02 48 8d 53 60 e9 e2 fd ff ff e8 3f
[ +0.000002] RSP: 0018:ffffb49ec0003c40 EFLAGS: 00010002
[ +0.000002] RAX: ffff940aa7a87790 RBX: ffff940ad762f700 RCX: 0000000000000000
[ +0.000002] RDX: ffff940aa7a87798 RSI: 0000000000000000 RDI: ffff940ad762a680
[ +0.000001] RBP: ffffb49ec0003c80 R08: ffff940ad6000920 R09: ffff940ad6000948
[ +0.000001] R10: 0000000000000000 R11: ffffffff9465e538 R12: 0000000000000041
[ +0.000002] R13: ffff940ad640ce00 R14: 0000000000002000 R15: ffff940aa7a87790
[ +0.000002] FS: 0000000000000000(0000) GS:ffff940ad7600000(0000) knlGS:0000000000000000
[ +0.000001] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ +0.000002] CR2: 0000347dbd847000 CR3: 000000013f40a004 CR4: 00000000001606f0
[ +0.000001] Call Trace:
[ +0.000002] <IRQ>
[ +0.000004] queue_work_on+0x3b/0x50
[ +0.000006] acm_write_bulk+0x70/0x80 [cdc_acm]
[ +0.000005] __usb_hcd_giveback_urb+0x7a/0x120
[ +0.000003] usb_hcd_giveback_urb+0xca/0xe0
[ +0.000003] xhci_giveback_urb_in_irq.isra.0+0x7b/0xf0
[ +0.000002] xhci_td_cleanup+0xf6/0x140
[ +0.000003] finish_td+0xcc/0x190
[ +0.000003] handle_tx_event+0x55d/0x11c0
[ +0.000003] xhci_irq+0x27a/0x3d0
[ +0.000002] xhci_msi_irq+0x11/0x13
[ +0.000005] __handle_irq_event_percpu+0x42/0x180
[ +0.000003] handle_irq_event_percpu+0x33/0x80
[ +0.000003] handle_irq_event+0x3b/0x5a
[ +0.000002] handle_edge_irq+0x93/0x1c0
[ +0.000003] do_IRQ+0x55/0xf0
[ +0.000003] common_interrupt+0xf/0xf
[ +0.000002] </IRQ>
[ +0.000003] RIP: 0010:cpuidle_enter_state+0xc5/0x450
[ +0.000002] Code: ff e8 bf 08 81 ff 80 7d c7 00 74 17 9c 58 0f 1f 44 00 00 f6 c4 02 0f 85 65 03 00 00 31 ff e8 12 6c 87 ff fb 66 0f 1f 44 00 00 <45> 85 ed 0f 88 8f 02 00 00 49 63 cd 4c 8b 7d d0 4c 2b 7d c8 48 8d
[ +0.000002] RSP: 0018:ffffffff94603de0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdc
[ +0.000002] RAX: ffff940ad762ad00 RBX: ffffffff94759c00 RCX: 000000000000001f
[ +0.000001] RDX: 0000000000000000 RSI: 000000003574f7ea RDI: 0000000000000000
[ +0.000001] RBP: ffffffff94603e20 R08: 000000367aa9c685 R09: 00000000000003b4
[ +0.000002] R10: ffff940ad7629a00 R11: ffff940ad76299e0 R12: ffff940ad7635300
[ +0.000001] R13: 0000000000000001 R14: 0000000000000001 R15: ffff940ad7635300
[ +0.000003] cpuidle_enter+0x2e/0x40
[ +0.000003] call_cpuidle+0x23/0x40
[ +0.000003] do_idle+0x1dd/0x270
[ +0.000002] cpu_startup_entry+0x20/0x30
[ +0.000003] rest_init+0xae/0xb0
[ +0.000005] arch_call_rest_init+0xe/0x1b
[ +0.000004] start_kernel+0x549/0x56a
[ +0.000004] x86_64_start_reservations+0x24/0x26
[ +0.000004] x86_64_start_kernel+0x75/0x79
[ +0.000004] secondary_startup_64+0xa4/0xb0
[ +0.000003] ---[ end trace 2ced5c1f97224540 ]---
[ +3.580766] cdc_acm 2-2:1.0: failed to set dtr/rts
---
ProblemType: Bug
ApportVersion: 2.20.11-0ubuntu27.6
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: jpmeijers 1934 F.... pulseaudio
/dev/snd/controlC1: jpmeijers 1934 F.... pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
DistroRelease: Ubuntu 20.04
InstallationDate: Installed on 2020-04-25 (127 days ago)
InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
MachineType: Dell Inc. XPS13 9333
Package: linux (not installed)
ProcFB: 0 i915drmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-42-generic root=UUID=ed37f80e-030b-472a-89f3-6b5a42539843 ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 5.4.0-42.46-generic 5.4.44
RelatedPackageVersions:
linux-restricted-modules-5.4.0-42-generic N/A
linux-backports-modules-5.4.0-42-generic N/A
linux-firmware 1.187.2
Tags: focal
Uname: Linux 5.4.0-42-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dialout dip docker lpadmin lxd plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 08/31/2015
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A08
dmi.board.name: 0GFTRT
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: 0.1
dmi.modalias: dmi:bvnDellInc.:bvrA08:bd08/31/2015:svnDellInc.:pnXPS139333:pvr:rvnDellInc.:rn0GFTRT:rvrA00:cvnDellInc.:ct8:cvr0.1:
dmi.product.family: Shark Bay System
dmi.product.name: XPS13 9333
dmi.product.sku: 060A
dmi.sys.vendor: Dell Inc.
apport information