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Subject: Re: [Qemu-devel] [PATCH v4 0/4] QOM'ify hw/char devices
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To: michael@walle.cc, Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-devel@nongnu.org, edgar.iglesias@gmail.com, agraf@suse.de, peter.maydell@linaro.org, Paolo Bonzini <paolo.bonzini@gmail.com>



在 2016年05月19日 21:45, michael@walle.cc 写道:
> Am 2016-05-19 13:32, schrieb Paolo Bonzini:
>> Michael, can you test patches 3 and 4?
>
> Doesn't work for me:
>   $ qemu-system-lm32 -kernel serial.bin -serial vc -serial vc
> Unexpected error in parse_chr() at 
> /home/mwalle/repos/qemu/hw/core/qdev-properties-system.c:149:
> qemu-system-lm32: Property 'lm32-uart.chardev' can't take value 
> 'serial0', it's in use
>
> serial0 seems already be claimed. Please note that even
>   $ qemu-system-lm32 -kernel serial.bin
> and
>   $ qemu-system-lm32
> does not work.
>
> "-serial .. -serial --" should still work, shouldn't it?
>
> I've uploaded a small test binary to http://milkymist.walle.cc/tests/ 
> which should prints 'A' and 'U' characters on the UARTs.
>
> -michael

Hi, michael:

It seems that qemu_char_get_next_serial()  call the qemu_chr_fe_claim, 
which is also called by
qdev_prop_set_chr ! This cause chr->avail_connectinos less than 1. as 
the error message said:
"it's in use".
A stright fix is to call the qemu_chr_fe_release after 
qemu_char_get_next_serial and the call the
qdev_prop_set_chr, the error is gone! I have test with your test cases 
and it works.

Or another way, can we modify qemu_char_get_next_serial and just skip 
the call of qemu_chr_fe_claim?