[Qemu-devel] Re: [PATCH] Disable O_DIRECT for physical CDROM/DVD drives

[Jes Sorensen]

On 07/20/10 18:03, Anthony Liguori wrote:
> On 07/20/2010 11:02 AM, Jes Sorensen wrote:
>> On 07/20/10 17:40, Anthony Liguori wrote:   
>>> Wouldn't a better solution be to have a cdrom_read/cdrom_write hook that
>>> did the appropriate bouncing?
>>>
>>> Silently disabling something a user explicitly asked for is not a good
>>> option.  In the very least, it should error out entirely.
>>>      
>> I thought about this, but it would require basically fixing up or
>> copying all of the pread/pwrite code to use the right block size. This
>> is really more of a band-aid but it should be pretty safe.
> 
> Please throw an error.  If a user explicitly asks for something, and we
> can provide it, we should not continue.  Changing it to something else
> is a bug.
> 
> That doesn't apply when we're changing a default value, but if the user
> asks for something, we should give it to them or fail.

Ok that seems fair enough! I'll post an updated patch in a minute.

Cheers,
Jes