Re: [Qemu-devel] Guest application reading from pl011 without device driver

[Paolo Bonzini]

> > I am using a windows named pipe to get the data from a window
> > host program, which uses ReadFile () in char_win.c
> 
> OK, bugs in the windows-specific char backend would be
> unsurprising.
> 
> I'm not entirely sure how the chardev layer works, but
> at the pl011 end if we return 0 from our can_receive
> function then the chardev layer should decide it has
> nothing to do until the pl011 later calls
> qemu_chr_fe_accept_input(), I think.
> 
> I've cc'd Paolo and Marc-André Lureau as the chardev
> maintainers.

Windows named pipes do not support the equivalent of "select",
so it's possible that they cause a busy wait.  Try using a
TCP socket instead and see if the bug goes away.

Paolo