On 2019/4/12 19:16, Joerg Roedel wrote: > On Tue, Apr 09, 2019 at 08:53:03PM +0800, Zhen Lei wrote: >> +static int __init iommu_dma_mode_setup(char *str) >> +{ >> + if (!str) >> + goto fail; >> + >> + if (!strncmp(str, "passthrough", 11)) >> + iommu_default_dma_mode = IOMMU_DMA_MODE_PASSTHROUGH; >> + else if (!strncmp(str, "lazy", 4)) >> + iommu_default_dma_mode = IOMMU_DMA_MODE_LAZY; >> + else if (!strncmp(str, "strict", 6)) >> + iommu_default_dma_mode = IOMMU_DMA_MODE_STRICT; >> + else >> + goto fail; >> + >> + pr_info("Force dma mode to be %d\n", iommu_default_dma_mode); > > Printing a number is not very desriptive or helpful to the user. Please > print the name of the mode instead. OK, thanks. I have given up adding iommu.dma_mode boot option according to Robin and Will's suggestion. So these codes will be removed in v6. > > > Regards, > > Joerg > > . > -- Thanks! BestRegards