Christoph Hellwig wrote:
> On Fri, Jun 01, 2007 at 09:01:45PM +0200, Andi Kleen wrote:
>> Bad idea imho. swiotlb mappings should always lead to printk by default
>> because it is pretty dangerous.
>>
>> One possible solution for this I could think of would be to define a
>> new pci_map_sg_couldfail() or similar that doesn't warn and use a weak
>> fallback just calling pci_map_sg on other IOMMU implementations. 
> 
> pci_map_sg is defined to be failing when running out of ressources, which
> is perfectly fine.  We don't printk on kmalloc failures either (actually
> in some cases which is highly annoying and leads people to stick a
> __GFP_NOWARN into various places)

Andi, I could see your "pretty dangerous" case applying
when do_panic is set, but not in any other circumstances.

Does the patch below look better to you?

Signed-off-by: Rik van Riel <riel@redhat.com>