Re: [Qemu-devel] [PATCH][v7] megasas: LSI Megaraid SAS emulation

[Hannes Reinecke]

On 07/19/2011 06:08 PM, Christoph Hellwig wrote:
> I've mentioned this a few times before, but just to make sure it's not
> lost:
>
> This is a really bad idea for adding to qemu.  It's not a controller that
> actually speaks a plain SCSI protocol to disks, but a RAID controller, that
> has it's own command set for data plan operation, and minimal support for
> a few SCSI CDBs around it.  I also supports passthrough channels for
> CDROMs and other periphals, but using those with disks is not recommended
> by LSI, thus explicitly disabled in most drivers and most certainly not
> tested.  So it fits the qemu model, especially if using scsi-generic
> undeneath pretty badly and I don't think it helps us in practice.
Hmm. This driver emulates an existing piece of hardware.
If the OS driver has shortcomings, okay, so be it.
But are there any rules which devices might be emulated and which 
shouldn't?

Cheers,

Hannes
--
Dr. Hannes Reinecke                   zSeries & Storage
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