Re: [Qemu-devel] [PATCH] virtio-scsi: Allocate op blocker reason before blocking

[Max Reitz <mreitz@redhat.com>]

On 2015-02-24 at 04:43, Markus Armbruster wrote:
> Max Reitz <mreitz@redhat.com> writes:
>
>> s->blocker is really only used in hw/scsi/virtio-scsi.c; the only places
>> where it is used in hw/scsi/virtio-scsi-dataplane.c is when it is
>> allocated and when it is freed. That does not make a whole lot of sense
>> (and is actually wrong because this leads to s->blocker potentially
>> being NULL when blk_op_block_all() is called in virtio-scsi.c), so move
>> the allocation and destruction of s->blocker to blk_op_block_all() and
>> blk_op_unblock_all() in virtio-scsi.c, respectively.
>>
>> Signed-off-by: Max Reitz <mreitz@redhat.com>
>> ---
>> Try:
>>
>> $ echo -e 'eject drv\nquit' | \
>>      x86_64-softmmu/qemu-system-x86_64 \
>>          -monitor stdio -machine accel=qtest -display none \
>>          -object iothread,id=thr -device virtio-scsi-pci,iothread=thr \
>>          -drive if=none,file=test.qcow2,format=qcow2,id=drv \
>>          -device scsi-cd,drive=drv
>>
>> What it should do:
>>
>> QEMU 2.2.50 monitor - type 'help' for more information
>> (qemu) eject drv
>> Device 'drv' is busy: block device is in use by data plane
>> (qemu) quit
>>
>> What it should not do:
>>
>> QEMU 2.2.50 monitor - type 'help' for more information
>> (qemu) eject drv
>> [1]    10102 done
>>         10103 segmentation fault (core dumped)
> Why do you put your nice reproducer below the --- divider?  I rather
> like bug fixing commits come with reproducers in the commit message.
>
> [...]

Because then I'm afraid that Eric complains because I used echo -e 
instead of printf.

Seriously speaking, I don't mind putting it into the commit message. 
I'll wait for reviews on the change itself, and then either send a v2 
with the reproducer included in the commit message or hope for a 
maintainer to fix it up himself (which I'd be totally fine with *hint 
hint*).

Max