USB Drive Crashes VM

vizsla

Member
Aug 27, 2017
23
2
8
Upper Midwest
I have Proxmox running a CentOS VM and two Linux Containers for a UniFi Controller and UniFi Video. I've included my VM configuration below. The system that runs on this VM has a nightly backup process that saves to a USB flash drive. As you can see in the config, I pass a USB port through to this VM. This has worked for 2.5 years, but recently when the USB flash drive is unplugged to be switched out for the other USB flash drive, the VM locks up. Once this happens, I can't access it through Proxmox VNC and the workstation application that interfaces with the system on the VM loses connection, so it appears the VM is completely crashing/freezing when the USB flash drive is unplugged. After stopping and starting the VM, the backup to USB process works and I've included a screen shot that Proxmox sees the USB flash drive on the port I have passed through to the VM. However, the moment the USB flash drive is unplugged, the VM crash happens again. Can I get some help troubleshooting this?

1590179772251.png

Virtual Machine Configuration
Code:
balloon: 8192
boot: cdn
bootdisk: scsi0
cores: 4
cpu: Skylake-Client
ide2: none,media=cdrom
memory: 14336
name: Rx30
net0: virtio=BE:D2:E3:F6:2C:40,bridge=vmbr0,firewall=1,queues=8
numa: 1
onboot: 1
ostype: l26
scsi0: local-lvm:vm-900-disk-1,discard=on,size=1T
scsihw: virtio-scsi-pci
smbios1: uuid=158fc4a2-7a7b-4699-980c-f45a45cb852d
sockets: 1
usb1: host=2-3,usb3=1
vga: qxl
 
do you see any log messages in the host/guest log?
 
do you see any log messages in the host/guest log?

Not much, but maybe I'm not looking in the right places? Here is what I have. With the Cent OS VM was running perfectly fine after booting it with the USB flash drive already inserted, I unplugged the USB flash drive and got the following log.
Code:
May 25 13:33:21 pve kernel: [310443.098278] usb 2-3: usbfs: usb_submit_urb returned -19
May 25 13:33:21 pve kernel: [310443.308499] usb 2-3: USB disconnect, device number 4

At this point, the Cent OS VM has frozen or crashed. The workstation applications that use the server have stopped working. The Proxmox console no longer works and any commands I type into the Monitor come back as failing. Example logs of me trying to connect to the VM:
Code:
May 25 13:34:46 pve pvedaemon[3674]: VM 900 qmp command failed - VM 900 qmp command 'human-monitor-command' $
May 25 13:34:54 pve qm[27135]: VM 900 qmp command failed - VM 900 qmp command 'change' failed - unable to co$
May 25 13:34:54 pve pvedaemon[27132]: Failed to run vncproxy.
May 25 13:34:54 pve pvedaemon[3674]: <root@pam> end task UPID:pve:000069FC:01D9BED2:5ECC0F91:vncproxy:900:ro$

If I STOP and START the Cent OS VM again without the USB flash drive plugged in, the VM boots but then freezes/crashes right when I plug the USB flash drive into it. The VM only seems to work now with the USB flash drive if I have the flash drive plugged in before I start the VM. Here's the log of starting the VM with the USB flash drive plugged in.
Code:
May 25 13:45:36 pve pvedaemon[29257]: starting vnc proxy UPID:pve:00007249:01DAD190:5ECC1250:vncproxy:900:ro$
May 25 13:45:45 pve kernel: [311187.402734] usb 2-3: reset SuperSpeed Gen 1 USB device number 10 using xhci_$
May 25 13:46:00 pve systemd[1]: Starting Proxmox VE replication runner...

I had been successfully using pve5-usb-automount in conjunction with hot swapping this USB flash drive with the Cent OS VM. When PVE 6.x broke this USB automount script, I could no longer plug in my USB external hard drive into a separate USB port for backup purposes, but my Cent OS VM was still working with hot swapping USB flash drives into the single USB port that is mapped to the VM. Not until around May 18 did the USB flash drive start freezing / crashing my Cent OS VM. I had run the usual "apt update" and "apt dist-upgrade" on the PVE server the day before, so I'm guessing that had something to do with it.

Finally, I have since replaced pve5-usb-automount with pve6-usb-automount, but that didn't help with my issue. I have removed pve6-usb-automount now and still no improvement. I'm mentioning this, because I thought it would be related, but it doesn't really seem to be, since it worked fine for a long time and it doesn't seem to me anything related to this changed when my VM freezing issue started occurring.
 
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Here is the Messages logging at the point that I disconnected the USB flash drive and the CentOS VM froze/crashed:
Code:
May 25 13:33:21 pve kernel: [310443.308499] usb 2-3: USB disconnect, device number 4
May 25 13:41:37 pve kernel: [310939.009120] fwbr900i0: port 2(tap900i0) entered disabled state
May 25 13:41:37 pve kernel: [310939.009356] fwbr900i0: port 2(tap900i0) entered disabled state
May 25 13:41:37 pve kernel: [310939.412095] fwbr900i0: port 1(fwln900i0) entered disabled state
May 25 13:41:37 pve kernel: [310939.412141] vmbr0: port 2(fwpr900p0) entered disabled state
May 25 13:41:37 pve kernel: [310939.412311] device fwln900i0 left promiscuous mode
May 25 13:41:37 pve kernel: [310939.412312] fwbr900i0: port 1(fwln900i0) entered disabled state
May 25 13:41:37 pve kernel: [310939.426019] device fwpr900p0 left promiscuous mode
May 25 13:41:37 pve kernel: [310939.426020] vmbr0: port 2(fwpr900p0) entered disabled state
May 25 13:42:04 pve kernel: [310966.139961] device tap900i0 entered promiscuous mode
May 25 13:42:04 pve kernel: [310966.165166] fwbr900i0: port 1(fwln900i0) entered blocking state
May 25 13:42:04 pve kernel: [310966.165167] fwbr900i0: port 1(fwln900i0) entered disabled state
May 25 13:42:04 pve kernel: [310966.165209] device fwln900i0 entered promiscuous mode
May 25 13:42:04 pve kernel: [310966.165229] fwbr900i0: port 1(fwln900i0) entered blocking state
May 25 13:42:04 pve kernel: [310966.165229] fwbr900i0: port 1(fwln900i0) entered forwarding state
May 25 13:42:04 pve kernel: [310966.167800] vmbr0: port 2(fwpr900p0) entered blocking state
May 25 13:42:04 pve kernel: [310966.167800] vmbr0: port 2(fwpr900p0) entered disabled state
May 25 13:42:04 pve kernel: [310966.167838] device fwpr900p0 entered promiscuous mode
May 25 13:42:04 pve kernel: [310966.167860] vmbr0: port 2(fwpr900p0) entered blocking state
May 25 13:42:04 pve kernel: [310966.167861] vmbr0: port 2(fwpr900p0) entered forwarding state
 
Last edited:
And here is the rest of the Messages logging:
Code:
May 25 13:42:04 pve kernel: [310966.170156] fwbr900i0: port 2(tap900i0) entered blocking state
May 25 13:42:04 pve kernel: [310966.170156] fwbr900i0: port 2(tap900i0) entered disabled state
May 25 13:42:04 pve kernel: [310966.170200] fwbr900i0: port 2(tap900i0) entered blocking state
May 25 13:42:04 pve kernel: [310966.170201] fwbr900i0: port 2(tap900i0) entered forwarding state
May 25 13:43:42 pve kernel: [311063.754163] usb 1-9: new high-speed USB device number 5 using xhci_hcd
May 25 13:43:43 pve kernel: [311065.090168] usb 1-9: new high-speed USB device number 6 using xhci_hcd
May 25 13:43:47 pve kernel: [311068.962174] usb 1-9: new high-speed USB device number 7 using xhci_hcd
May 25 13:43:48 pve kernel: [311069.918219] usb 2-3: new SuperSpeed Gen 1 USB device number 7 using xhci_hcd
May 25 13:43:48 pve kernel: [311069.939277] usb 2-3: New USB device found, idVendor=154b, idProduct=00ed, bc$
May 25 13:43:48 pve kernel: [311069.939278] usb 2-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
May 25 13:43:48 pve kernel: [311069.939279] usb 2-3: Product: USB 3.0 FD
May 25 13:43:48 pve kernel: [311069.939280] usb 2-3: Manufacturer: PNY
May 25 13:43:48 pve kernel: [311069.939280] usb 2-3: SerialNumber: 0700968C88FB1128
May 25 13:43:48 pve kernel: [311069.940197] usb 2-3: Set SEL for device-initiated U2 failed.
May 25 13:43:48 pve kernel: [311069.940236] usb-storage 2-3:1.0: USB Mass Storage device detected
May 25 13:43:48 pve kernel: [311069.940466] scsi host7: usb-storage 2-3:1.0
May 25 13:43:48 pve kernel: [311070.342189] usb 2-3: USB disconnect, device number 7
May 25 13:43:49 pve kernel: [311070.910184] usb 1-9: new high-speed USB device number 8 using xhci_hcd
May 25 13:43:50 pve kernel: [311071.866261] usb 2-3: new SuperSpeed Gen 1 USB device number 8 using xhci_hcd
May 25 13:43:50 pve kernel: [311071.887305] usb 2-3: New USB device found, idVendor=154b, idProduct=00ed, bc$
May 25 13:43:50 pve kernel: [311071.887306] usb 2-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
May 25 13:43:50 pve kernel: [311071.887307] usb 2-3: Product: USB 3.0 FD
May 25 13:43:50 pve kernel: [311071.887308] usb 2-3: Manufacturer: PNY
May 25 13:43:50 pve kernel: [311071.887308] usb 2-3: SerialNumber: 0700968C88FB1128
May 25 13:43:50 pve kernel: [311071.888408] usb-storage 2-3:1.0: USB Mass Storage device detected
May 25 13:43:50 pve kernel: [311071.888614] scsi host7: usb-storage 2-3:1.0
May 25 13:43:51 pve kernel: [311072.898922] scsi 7:0:0:0: Direct-Access     PNY      USB 3.0 FD       PMAP P$
May 25 13:43:51 pve kernel: [311072.899162] sd 7:0:0:0: Attached scsi generic sg2 type 0
May 25 13:43:51 pve kernel: [311072.899376] sd 7:0:0:0: [sdb] 121110528 512-byte logical blocks: (62.0 GB/57$
May 25 13:43:51 pve kernel: [311072.899589] sd 7:0:0:0: [sdb] Write Protect is off
May 25 13:43:51 pve kernel: [311072.899786] sd 7:0:0:0: [sdb] Write cache: disabled, read cache: enabled, do$
May 25 13:43:51 pve kernel: [311072.965530]  sdb: sdb1
May 25 13:43:51 pve kernel: [311072.966713] sd 7:0:0:0: [sdb] Attached SCSI removable disk
May 25 13:43:51 pve kernel: [311073.270192] usb 2-3: USB disconnect, device number 8
May 25 13:43:51 pve kernel: [311073.270245] xhci_hcd 0000:00:14.0: WARN Set TR Deq Ptr cmd failed due to inc$
May 25 13:43:51 pve kernel: [311073.270268] sd 7:0:0:0: [sdb] tag#0 FAILED Result: hostbyte=DID_ERROR driver$
May 25 13:43:51 pve kernel: [311073.270270] sd 7:0:0:0: [sdb] tag#0 CDB: Read(10) 28 00 07 37 fe f8 00 00 08$
May 25 13:43:52 pve kernel: [311073.918267] usb 2-3: new SuperSpeed Gen 1 USB device number 9 using xhci_hcd
May 25 13:43:53 pve kernel: [311074.666273] usb 2-3: new SuperSpeed Gen 1 USB device number 10 using xhci_hcd
May 25 13:43:53 pve kernel: [311074.687391] usb 2-3: New USB device found, idVendor=154b, idProduct=00ed, bc$
May 25 13:43:53 pve kernel: [311074.687392] usb 2-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
May 25 13:43:53 pve kernel: [311074.687393] usb 2-3: Product: USB 3.0 FD
May 25 13:43:53 pve kernel: [311074.687393] usb 2-3: Manufacturer: PNY
May 25 13:43:53 pve kernel: [311074.687394] usb 2-3: SerialNumber: 0700968C88FB1128
May 25 13:43:53 pve kernel: [311074.688396] usb-storage 2-3:1.0: USB Mass Storage device detected
May 25 13:43:53 pve kernel: [311074.688557] scsi host7: usb-storage 2-3:1.0
May 25 13:43:54 pve kernel: [311075.714884] scsi 7:0:0:0: Direct-Access     PNY      USB 3.0 FD       PMAP P$
May 25 13:43:54 pve kernel: [311075.715160] sd 7:0:0:0: Attached scsi generic sg2 type 0
May 25 13:43:54 pve kernel: [311075.715453] sd 7:0:0:0: [sdb] 121110528 512-byte logical blocks: (62.0 GB/57$
May 25 13:43:54 pve kernel: [311075.715662] sd 7:0:0:0: [sdb] Write Protect is off
May 25 13:43:54 pve kernel: [311075.715934] sd 7:0:0:0: [sdb] Write cache: disabled, read cache: enabled, do$
May 25 13:43:54 pve kernel: [311075.740120]  sdb: sdb1
May 25 13:43:54 pve kernel: [311075.741317] sd 7:0:0:0: [sdb] Attached SCSI removable disk
May 25 13:45:28 pve kernel: [311170.094175] fwbr900i0: port 2(tap900i0) entered disabled state
May 25 13:45:28 pve kernel: [311170.094367] fwbr900i0: port 2(tap900i0) entered disabled state
May 25 13:45:29 pve kernel: [311170.876853] fwbr900i0: port 1(fwln900i0) entered disabled state
May 25 13:45:36 pve kernel: [311177.920402] device tap900i0 entered promiscuous mode
May 25 13:45:36 pve kernel: [311177.946030] fwbr900i0: port 1(fwln900i0) entered blocking state
May 25 13:45:36 pve kernel: [311177.946031] fwbr900i0: port 1(fwln900i0) entered disabled state
May 25 13:45:36 pve kernel: [311177.946071] device fwln900i0 entered promiscuous mode
May 25 13:45:36 pve kernel: [311177.946092] fwbr900i0: port 1(fwln900i0) entered blocking state
May 25 13:45:36 pve kernel: [311177.946093] fwbr900i0: port 1(fwln900i0) entered forwarding state
May 25 13:45:36 pve kernel: [311177.948637] vmbr0: port 2(fwpr900p0) entered blocking state
May 25 13:45:36 pve kernel: [311177.948638] vmbr0: port 2(fwpr900p0) entered disabled state
May 25 13:45:36 pve kernel: [311177.948676] device fwpr900p0 entered promiscuous mode
May 25 13:45:36 pve kernel: [311177.948697] vmbr0: port 2(fwpr900p0) entered blocking state
May 25 13:45:36 pve kernel: [311177.948698] vmbr0: port 2(fwpr900p0) entered forwarding state
May 25 13:45:36 pve kernel: [311177.951059] fwbr900i0: port 2(tap900i0) entered blocking state
May 25 13:45:36 pve kernel: [311177.951060] fwbr900i0: port 2(tap900i0) entered disabled state
May 25 13:45:36 pve kernel: [311177.951105] fwbr900i0: port 2(tap900i0) entered blocking state
May 25 13:45:36 pve kernel: [311177.951106] fwbr900i0: port 2(tap900i0) entered forwarding state
May 25 13:45:45 pve kernel: [311187.402734] usb 2-3: reset SuperSpeed Gen 1 USB device number 10 using xhci_$
May 25 13:52:29 pve kernel: [311590.662522] usb 2-3: reset SuperSpeed Gen 1 USB device number 10 using xhci_$
May 25 13:52:30 pve kernel: [311591.770417] usb 2-3: reset SuperSpeed Gen 1 USB device number 10 using xhci_$
May 25 13:52:30 pve kernel: [311592.038554] usb 2-3: reset SuperSpeed Gen 1 USB device number 10 using xhci_$

{... a lot more of this ...}

May 25 13:52:37 pve kernel: [311598.626498] usb 2-3: reset SuperSpeed Gen 1 USB device number 10 using xhci_$
May 25 13:52:37 pve kernel: [311598.647493] usb 2-3: Enable of device-initiated U2 failed.
May 25 13:52:37 pve kernel: [311598.894509] usb 2-3: reset SuperSpeed Gen 1 USB device number 10 using xhci_$

{... a lot more of this ...}

May 25 14:13:12 pve kernel: [312833.958268] EXT4-fs (dm-6): mounted filesystem with ordered data mode. Opts:$
May 25 14:13:12 pve kernel: [312834.476280] audit: type=1400 audit(1590433992.981:42): apparmor="STATUS" ope$
May 25 14:13:13 pve kernel: [312834.825663] fwbr100i0: port 1(fwln100i0) entered blocking state
May 25 14:13:13 pve kernel: [312834.825664] fwbr100i0: port 1(fwln100i0) entered disabled state
May 25 14:13:13 pve kernel: [312834.825707] device fwln100i0 entered promiscuous mode
May 25 14:13:13 pve kernel: [312834.825732] fwbr100i0: port 1(fwln100i0) entered blocking state
May 25 14:13:13 pve kernel: [312834.825733] fwbr100i0: port 1(fwln100i0) entered forwarding state
May 25 14:13:13 pve kernel: [312834.828108] vmbr0: port 3(fwpr100p0) entered blocking state
May 25 14:13:13 pve kernel: [312834.828108] vmbr0: port 3(fwpr100p0) entered disabled state
May 25 14:13:13 pve kernel: [312834.828148] device fwpr100p0 entered promiscuous mode
May 25 14:13:13 pve kernel: [312834.828162] vmbr0: port 3(fwpr100p0) entered blocking state
May 25 14:13:13 pve kernel: [312834.828162] vmbr0: port 3(fwpr100p0) entered forwarding state
May 25 14:13:13 pve kernel: [312834.830303] fwbr100i0: port 2(veth100i0) entered blocking state
May 25 14:13:13 pve kernel: [312834.830304] fwbr100i0: port 2(veth100i0) entered disabled state
May 25 14:13:13 pve kernel: [312834.830339] device veth100i0 entered promiscuous mode
May 25 14:13:13 pve kernel: [312834.850127] eth0: renamed from vethBbqv7p
May 25 14:13:13 pve kernel: [312834.997208] audit: type=1400 audit(1590433993.500:43): apparmor="DENIED" ope$
May 25 14:13:15 pve kernel: [312837.468613] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
May 25 14:13:15 pve kernel: [312837.468632] fwbr100i0: port 2(veth100i0) entered blocking state
May 25 14:13:15 pve kernel: [312837.468633] fwbr100i0: port 2(veth100i0) entered forwarding state
May 25 14:13:16 pve kernel: [312838.183701] EXT4-fs (dm-8): mounted filesystem with ordered data mode. Opts:$
May 25 14:13:16 pve kernel: [312838.405168] EXT4-fs (dm-9): mounted filesystem with ordered data mode. Opts:$
May 25 14:13:17 pve kernel: [312838.684815] audit: type=1400 audit(1590433997.188:44): apparmor="STATUS" ope$
 
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Yes, I faced the same problem as you. VM freezes if you pull out the USB device that the OS is accessing. Everything used to work fine before. The only way that I have found so far is to correctly stop the call and disconnect the device from inside the guest system.
 
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Hello. I have the exact same problem on my PVE server. When I disconnect a serial port USB device (FTDI) while used, the guest crash.
I have found nothing in the logs (host and VM). The problem occurs on a Linux guest, FreeBSD and Windows as well.
This problem has appeared when I upgraded Proxmox from 5 to 6. Seems to be related to KVM maybe?
 
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Is there any way to downgrade Proxmox while this gets fixed?
I'm not entirely sure anyone has acknowledged this as an issue to be fixed yet.

I think you would downgrade using something like apt-get install proxmox-ve-6.1-2, but you'd want to do a little more investigating before taking my quick comment. I have no clue what concerns there might be about that breaking something.
 
I'm not entirely sure anyone has acknowledged this as an issue to be fixed yet.

I think you would downgrade using something like apt-get install proxmox-ve-6.1-2, but you'd want to do a little more investigating before taking my quick comment. I have no clue what concerns there might be about that breaking something.
This only downgrades Proxmox's meta package. We'd need to downgrade qemu, but there are many dependencies, so I don't think it's possible. I'll have to wait I guess :/
 
I managed to downgrade using this command:
apt install proxmox-ve=6.1-2 pve-manager=6.1-11 pve-kernel-helper=6.1-9 corosync=3.0.3-pve1 criu=3.11-3 glusterfs-client=5.5-3 ifupdown=0.8.35+pve1 ksm-control-daemon=1.3-1 libjs-extjs=6.0.1-10 libknet1=1.15-pve1 libproxmox-acme-perl=1.0.2 libpve-access-control=6.0-7 libpve-apiclient-perl=3.0-3 libpve-common-perl=6.1-1 libpve-guest-common-perl=3.0-10 libpve-http-server-perl=3.0-5 libpve-storage-perl=6.1-7 libqb0=1.0.5-1 libspice-server1=0.14.2-4~pve6+1 lvm2=2.03.02-pve4 lxc-pve=4.0.2-1 lxcfs=4.0.3-pve2 novnc-pve=1.1.0-1 proxmox-mini-journalreader=1.1-1 proxmox-widget-toolkit=2.1-6 pve-cluster=6.1-8 pve-container=3.1-4 pve-docs=6.1-6 pve-edk2-firmware=2.20200229-1 pve-firewall=4.1-2 pve-firmware=3.0-7 pve-ha-manager=3.0-9 pve-i18n=2.1-1 pve-qemu-kvm=4.1.1-4 pve-xtermjs=4.3.0-1 qemu-server=6.1-20 smartmontools=7.1-pve2 spiceterm=3.1-1 vncterm=1.6-1

It doesn't freeze anymore. Use at your own risk though.
 
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I did an Upgrade today, but the bug is still the same, freeze after disconnect an USB.

proxmox-ve: 6.2-1 (running kernel: 5.4.41-1-pve)
pve-manager: 6.2-6 (running version: 6.2-6/ee1d7754)
pve-kernel-5.4: 6.2-2
pve-kernel-helper: 6.2-2
pve-kernel-5.3: 6.1-6
pve-kernel-5.4.41-1-pve: 5.4.41-1
pve-kernel-5.4.34-1-pve: 5.4.34-2
pve-kernel-5.3.18-3-pve: 5.3.18-3
pve-kernel-5.3.10-1-pve: 5.3.10-1
ceph-fuse: 12.2.11+dfsg1-2.1+b1
corosync: 3.0.3-pve1 criu: 3.11-3
glusterfs-client: 5.5-3
ifupdown: not correctly installed
ifupdown2: 3.0.0-1+pve2
ksm-control-daemon: 1.3-1
libjs-extjs: 6.0.1-10 libknet1: 1.15-pve1
libproxmox-acme-perl: 1.0.4
libpve-access-control: 6.1-1
libpve-apiclient-perl: 3.0-3
libpve-common-perl: 6.1-3
libpve-guest-common-perl: 3.0-10
libpve-http-server-perl: 3.0-5
libpve-storage-perl: 6.1-8
libqb0: 1.0.5-1
libspice-server1: 0.14.2-4~pve6+1
lvm2: 2.03.02-pve4
lxc-pve: 4.0.2-1
lxcfs: 4.0.3-pve2
novnc-pve: 1.1.0-1
proxmox-mini-journalreader: 1.1-1
proxmox-widget-toolkit: 2.2-7
pve-cluster: 6.1-8
pve-container: 3.1-8
pve-docs: 6.2-4
pve-edk2-firmware: 2.20200229-1
pve-firewall: 4.1-2
pve-firmware: 3.1-1
pve-ha-manager: 3.0-9
pve-i18n: 2.1-3
pve-qemu-kvm: 5.0.0-4
pve-xtermjs: 4.3.0-1
qemu-server: 6.2-3
smartmontools: 7.1-pve2
spiceterm: 3.1-1
vncterm: 1.6-1
zfsutils-linux: 0.8.4-pve1
 
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I did a upgrade today. The problem is fixed for me.
Dang. I just installed the following, rebooted PVE, and then tested this... and pulling the USB drive out of the server still locked up / froze / crashed the Linux VM that has the USB drive passed to it. Do you know why you also got pve-kernel-5.4.44-1-pve: 5.4.44-1? Edit: Looks like I just already had that installed is all.

1592522448160.png
 
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I updated to pve-kernel-5.4 (6.2-4). Ran my first test this morning by restarting my server with the USB flash drive plugged in. My VM recognized the flash drive. I unplugged it, the VM didn't freeze/crash, and I could see in the CentOS VM that it had been disconnected. I then plugged my next rotation USB flash drive in and CentOS showed it mount and the VM did not freeze. I'll keep trying this to see if the issue is gone or if this was a fluke.
 
Checked with the latest kernel version - the VM still breaks if you remove the mounted USB drive
 

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