On Thu, Nov 19 2020 at 12:59, Andrea Arcangeli wrote: > If reserved memory is mapped with ioremap_noncache() or ioremap_wc(), > the kernel correctly splits the direct mapping and marks the PAGE_SIZE > granular region uncached, so both the virtual direct mapping and the > second virtual mapping in vmap space will be both marked uncached or > write through (i.e. _PAGE_PCD/PWT set on the pagetable). > > However when iounmap is called later, nothing restores the direct > mapping write back memtype.
Darn. This was discussed in 2008 already and survived that long? https://lore.kernel.org/lkml/[email protected]/ No idea how that happened to slip through... Thanks, tglx
