Re: [Nouveau] kernel spew from nouveau/ swiotlb

[Jerome Glisse <jglisse@redhat.com>]

> Greetings,
> 
> When box is earning its keep, nouveau/swiotlb grumble.. a LOT.  The
> below is from master.today.
> 
> [12594.640959] nouveau 0000:01:00.0: swiotlb buffer is full (sz: 2097152
> bytes)
> [12594.693000] nouveau 0000:01:00.0: swiotlb buffer is full (sz: 2097152
> bytes)
> [12594.713787] nouveau 0000:01:00.0: swiotlb buffer is full (sz: 2097152
> bytes)
> [12594.743413] nouveau 0000:01:00.0: swiotlb buffer is full (sz: 2097152
> bytes)
> [12594.796740] nouveau 0000:01:00.0: swiotlb buffer is full (sz: 2097152
> bytes)
> [12607.000774] swiotlb_tbl_map_single: 54 callbacks suppressed
> [12607.000776] nouveau 0000:01:00.0: swiotlb buffer is full (sz: 2097152
> bytes)
> [12607.347941] nouveau 0000:01:00.0: swiotlb buffer is full (sz: 2097152
> bytes)
> [12608.677038] nouveau 0000:01:00.0: swiotlb buffer is full (sz: 2097152
> bytes)
> homer:/novell/ssh # dmesg|grep 'swiotlb buffer is full'|wc -l
> 2052
> homer:/novell/ssh # dmesg|grep 'callbacks suppressed'|wc -l
> 171
> 
> lib/swiotlb.c:
>  573 not_found:
>  574         spin_unlock_irqrestore(&io_tlb_lock, flags);
>  575         if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit())
>  576                 dev_warn(hwdev, "swiotlb buffer is full (sz: %zd
>  bytes)\n", size);
> 
> Does nouveau perhaps want one of those DMA_ATTR_NO_WARN thingies?
> 

Could you bisect ? I would love to point finger upstream to the DMA
folk who made changes to that API without testing with GPU.

Cheers,
Jérôme