On Friday 24 January 2014 02:25 PM, Konrad Rzeszutek Wilk wrote: > On Fri, Jan 24, 2014 at 11:11:10AM -0800, Yinghai Lu wrote: >> The new memblock_virt APIs are used to replaced old bootmem API. >> >> We need to allocate page below 4G for swiotlb. >> >> That should fix regression on Andrew's system that is using swiotlb. > > Please include the title of the patch that caused the regression. > I presume it is "mm/lib/swiotlb: Use memblock apis for early memory > allocations" > > Interestingly enough when I asked about it: > > https://lkml.org/lkml/2013/11/9/280 > > > >> v_overflow_buffer = memblock_virt_alloc_align_nopanic( > >> + > PAGE_ALIGN(io_tlb_overflow), > >> + PAGE_SIZE); > > > > Does this guarantee that the pages will be allocated below 4GB? > > > Yes. The memblock layer still allocates memory from lowmem. As I > mentioned, there is no change in the behavior than what is today > apart from just the interface change. > > How did that happend? Was there another patch in the series that altered > such assumption? > Actually it didn't. It was the misunderstanding on my side about the low_mem_max_addr being under 4GB, which is not always true especially for 64-bit systems which have no addressing limitations.
Regards, Santosh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
