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    SubjectRe: task hung in port100_send_cmd_sync
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    On 18/09/2022 15:22, Rondreis wrote:
    > Hello,
    >
    > When fuzzing the Linux kernel driver v6.0-rc4, the following crash was
    > triggered.

    Hi,

    Thanks for the report.

    >
    > HEAD commit: 7e18e42e4b280c85b76967a9106a13ca61c16179
    > git tree: upstream
    >
    > kernel config: https://pastebin.com/raw/xtrgsXP3
    > C reproducer: https://pastebin.com/raw/hjSnLzDh
    > console output: https://pastebin.com/raw/3ixbVNcR
    >
    > Basically, in the c reproducer, we use the gadget module to emulate
    > attaching a USB device(vendor id: 0x54c, product id: 0x6c1, with the
    > printer function) and executing some simple sequence of system calls.
    > To reproduce this crash, we utilize a third-party library to emulate
    > the attaching process: https://github.com/linux-usb-gadgets/libusbgx.
    > Just clone this repository, install it, and compile the c
    > reproducer with ``` gcc crash.c -lusbgx -lconfig -o crash ``` will do
    > the trick.
    >
    > I would appreciate it if you have any idea how to solve this bug.

    You can try to bisect. Or you can build kernel with lockdep and try to
    reproduce.

    >
    > The crash report is as follows:

    It's not a crash, but a blocked task, so there might be deadlock,
    incorrect synchronization or some missing cleanup path. Actually quite a
    lot could lead to this.

    Best regards,
    Krzysztof

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