[Spice-devel] [PATCH] char-device: spice_char_device_write_to_device: protect against recursion

[Marc-André Lureau]

Hi

----- Original Message -----
> This fixes Spice's smart card support and is related to
> commit 697f3214fd16adcd524456003619f7f44ddd031b.
> 
> Reported-by: Swapna Krishnan <skrishna at redhat.com>
> 
> Recursion is now possible starting with spice_char_device_wakeup calling
>  spice_char_device_write_to_device that later (after going through qemu)
> calls spice_char_device_wakeup.
> 
> The protecting code is the same to the one in the read path.
> 
> This function call loop makes the program to abort with the following
> messages:
> 
>   usb-ccid: chardev: unexpected message of type 3000000
>   qemu: qemu_mutex_lock: Resource deadlock avoided
> ---
> 
> Should I attach the backtrace in the commit message ?

Yes, please.