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Subject: Re: [Qemu-devel] virtio-scsi + iothread : segfault on drive_del
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To: Alexandre DERUMIER <aderumier@odiso.com>, qemu-devel <qemu-devel@nongnu.org>



On 01/04/2015 05:34, Alexandre DERUMIER wrote:
> 
> I'm currently testing virtio-scsi and iothread,
> 
> and I'm seeing qemu segfault when I try to remove an scsi drive 
> on top of an virtio-scsi controller with iothread enabled.
> 
> 
> virtio-blk + iothread  drive_del is supported since this patch
> 
> http://comments.gmane.org/gmane.comp.emulators.qemu/291562
> "block: support drive_del with dataplane
> 
> This series makes hot unplug work with virtio-blk dataplane devices.  It should
> also work with Fam's virtio-scsi dataplane patches."

virtio-scsi + iothread is experimental and not yet thread-safe.

Deadlocks or crashes are expected, and not really fixable without a lot
of preparatory changes to core QEMU code.  These are being done, but I
don't expect it to be fixed before 2.5.

Paolo