[Bug 221103] New: xhci_hcd: System lockup under CPU load during rapid usbfs polling of SuperSpeed root hubs on AMD Ryzen platforms

[bugzilla-daemon@kernel.org]

https://bugzilla.kernel.org/show_bug.cgi?id=221103

            Bug ID: 221103
           Summary: xhci_hcd: System lockup under CPU load during rapid
                    usbfs polling of SuperSpeed root hubs on AMD Ryzen
                    platforms
           Product: Drivers
           Version: 2.5
    Kernel Version: 6.12 - 6.19, (and mainline)
          Hardware: AMD
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P3
         Component: USB
          Assignee: drivers_usb@kernel-bugs.kernel.org
          Reporter: paul@unnservice.com
        Regression: No

Created attachment 309401
  --> https://bugzilla.kernel.org/attachment.cgi?id=309401&action=edit
Test program that polls USB nodes and triggers the system freeze

On multiple AMD Ryzen 7000/9000-series systems (X670E/X870 motherboards with
recent AGESA firmware) rapidly polling xHCI device nodes via usbfs can cause a
complete system freeze.

Reproduction:
1. Compile/run the attached usb_poll.c
2. Create CPU load (stress-ng --cpu 0 works reliably)
3. On affected machines the system freezes within a few minutes without any log

The trigger on my system is consistently one of the SuperSpeed (USB 3.x 10
Gbps) xHCI root hubs (1d6b:0003). I cannot confirm if other affected users
freeze on exactly the same device node, but all reports point to the same class
bug polling xHCI.

Kernels affected:
6.12 - 6.18 (LTS + mainline) on openSUSE Tumbleweed, Manjaro, Ubuntu, Gentoo,
Bazzite, Fedora, etc.

I can provide any additional diagnostics needed:
- Full lsusb -t -v and lsusb -vvv
- lspci -vvv

My MB and CPU, others in the ADB bug report have different AMD systems:
- Motherboard: Asus ProArt X870-E CREATOR
- CPU: AMD Ryzen 9 9950X

Originally exposed by ADB’s USB backend (platform-tools ≥ 36.0.2):
https://issuetracker.google.com/issues/472398009 (full discussion with many
affected users)

Tests:

test: Poll all USB devices
method: usb_poll.c
iterations: 600
result: SYSTEM FREEZE opening Bus 010 Device 001: ID 1d6b:0003 Linux Foundation
3.0 root hub

test: Skip all root hubs (Device 001 on all busses)
method: usb_poll.c
iterations: 2400
result: SUCCESS

test: Only root hubs
method: usb_poll.c
iterations: 159
result: SYSTEM FREEZE opening Bus 010 Device 001: ID 1d6b:0003 Linux Foundation
3.0 root hub

test: All devices except Bus 010 Device 001
method: usb_poll.c
iterations: 1900
result: SUCCESS

test: Only the specific xHCI root hub
method: usb_poll.c
iterations: 209
result: SYSTEM FREEZE

test: Only the specific xHCI root hub
method: while true; do sudo lsusb -v -s 010:001 >/dev/null; sleep 0.1; done
iterations: 2400
result: SUCCESS

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