Re: [PATCH v2] usb: xhci: Fix sleep in atomic context in xhci_free_streams()

[Mathias Nyman]

On 6/12/26 09:29, 胡连勤 wrote:
> When a USB device with active stream endpoints is disconnected,
> xhci_free_streams() is called from the hub_event workqueue to
> free the stream resources.  It calls xhci_free_stream_info()
> while holding xhci->lock with irqs disabled.
>
> xhci_free_stream_info() invokes xhci_free_stream_ctx(), which
> calls dma_free_coherent() for large stream context arrays.
>
> dma_free_coherent() can sleep (e.g. via vunmap), triggering
> a BUG when called from atomic context.
>
> Call trace:
>   dma_free_attrs+0x174/0x220
>   xhci_free_stream_info+0xd0/0x11c
>   xhci_free_streams+0x278/0x37c
>   usb_free_streams+0x98/0xc0
>   usb_unbind_interface+0x1b8/0x2f8
>   device_release_driver_internal+0x1d4/0x2cc
>   device_release_driver+0x18/0x28
>   bus_remove_device+0x160/0x1a4
>   device_del+0x1ec/0x350
>   usb_disable_device+0x98/0x214
>   usb_disconnect+0xf0/0x35c
>   hub_event+0xab4/0x19ec
>   process_one_work+0x278/0x63c
>
> Fix this by saving the stream_info pointers and clearing the
> ep references under the lock, then calling xhci_free_stream_info()
> outside the lock where sleeping is allowed.
>
> Fixes: 8df75f42f8e6 ("USB: xhci: Add memory allocation for USB3 bulk streams.")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Lianqin Hu <hulianqin@xxxxxxxx>


Applied, needed some manual work

Line endings (CR/CRLF) of this patch got mangled somewhere on the way (mail client?).

Checkpatch also complained about "From" and "Signed-off-by" mismatch.
胡连勤 != Lianqin Hu according to script, But this can probably be ignored

Thanks
Mathias