On Mon, 1 Aug 2016 19:59:47 -0300 Mauricio Faria de Oliveira <mauricfo@xxxxxxxxxxxxxxxxxx> wrote: > This patchset introduces dma_attr DMA_ATTR_NO_WARN (just like __GFP_NOWARN), > which tells the DMA-mapping subsystem to suppress allocation failure reports. > > On some architectures allocation failures are reported with error messages > to the system logs. Although this can help to identify and debug problems, > drivers which handle failures (eg, retry later) have no problems with them, > and can actually flood the system logs with error messages that aren't any > problem at all, depending on the implementation of the retry mechanism. It would help to have seen an example of the error message - please always quote such things when fixing bugs. I assume the warnings are coming via nvme_map_data()'s call to blk_rq_map_sg()? An alternative (and more idiomatic) fix would be to change the blk_rq_map_sg() interface to permit passing down some foo_NOWARN flag and propagating that down the stack into ppc_iommu_map_sg(). Was this approach evaluated? I suspect it might be messy. -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
