On Mon, Apr 8, 2013 at 12:09 AM, Dave Young <dyo...@redhat.com> wrote: >> We have now modified crashkernel=X to allocate memory beyong 4G (if >> available) and do not allocate low range for crashkernel if the user >> does not specify that with crashkernel_low=Y. This causes regression >> if iommu is not enabled. Without iommu, swiotlb needs to be setup in >> first 4G and there is no low memory available to second kernel. > > Is it possible to reuse the 1st kernel swiotlb region in 2nd capture > kernel if it's available?
If the first kernel is using intel iommu, and swiotlb is freed after intel iommus is enabled in first kernel. > >> >> Set crashkernel_low automatically if the user does not specify that. >> >> For system that does support IOMMU with kdump properly, user could >> specify crashkernel_low=0 to save that 72M low ram. > > How about make swiotlb size tunable in 1st kernel as well such as adding > a swiotlb_size= to cmdline, if it's set in 1st kernel crashkernel > reserving code can take it automaticlly. > can not understand this. Thanks Yinghai -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
