On Thu, Jan 27, 2022 at 10:08:33AM -0800, Ira Weiny wrote: > On Thu, Jan 27, 2022 at 10:57:30AM +0100, Christoph Hellwig wrote: > > On Thu, Jan 27, 2022 at 09:37:59AM +0000, yangx.jy@xxxxxxxxxxx wrote: > > > Do you mean we have to consider that some allocated pages come from high > > > memory? > > > > > > I think INFINIBAND_VIRT_DMA kconfig[1] has ensured that all allocated > > > pages have a kernel virtual address. > > > > rxe and siw depend on INFINIBAND_VIRT_DMA which depends on !HIGHMEM, > > so you don't need kmap here at all. > > Until/if I get PKS protecting pmem.[1] Then if the page is pmem, page_address() > will give you an address which you will fault on when you access it. In that case we'll have problems all over the drivers that select INFINIBAND_VIRT_DMA, so this one doesn't make much of a difference..
