Paolo Bonzini [off-list ref] writes:

Il 04/10/2012 14:51, Rusty Russell ha scritto:

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Paolo Bonzini [off-list ref] writes:

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Il 04/10/2012 02:11, Rusty Russell ha scritto:

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There's a reason I haven't done this.  I really, really dislike "my
implemention isn't broken" feature bits.  We could have an infinite
number of them, for each bug in each device.

However, this bug affects (almost) all implementations and (almost) all
devices.  It even makes sense to reserve a transport feature bit for it
instead of a device feature bit.

Perhaps, but we have to fix the bugs first!

Yes. :)  Isn't that what mst's patch does?

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As I said, my torture patch broke qemu immediately.  Since noone has
leapt onto fixing that, I'll take a look now...

I can look at virtio-scsi.

Actually, you can't, see my reply to Anthony...

Message-ID: [ref]

    struct virtio_scsi_req_cmd {
        // Read-only
        u8 lun[8];
        u64 id;
        u8 task_attr;
        u8 prio;
        u8 crn;
        char cdb[cdb_size];
        char dataout[];
        // Write-only part
        u32 sense_len;
        u32 residual;
        u16 status_qualifier;
        u8 status;
        u8 response;
        u8 sense[sense_size];
        char datain[];
    };

where cdb_size and sense_size come from configuration space.  The device
right now expects everything before dataout/datain to be in a single
descriptor, but that's in no way part of the spec.  Am I missing
something egregious?

Since you wrote it, I hope not :)

That's good.  But virtio_blk's scsi command is insoluble AFAICT.  As I
said to Anthony, the best rules are "always" and "never", so I'd really
rather not have to grandfather that in.

Cheers,
Rusty.