On Fri, 21 Aug 2020 14:37:46 +0200 Joerg Roedel <joro@xxxxxxxxxx> wrote: > The __apply_to_page_range() function is also used to change and/or > allocate page-table pages in the vmalloc area of the address space. > Make sure these changes get synchronized to other page-tables in the > system by calling arch_sync_kernel_mappings() when necessary. There's no description here of the user-visible effects of the bug. Please always provide this, especially when proposing a -stable backport. Take pity upon all the downstream kernel maintainers who are staring at this wondering whether they should risk adding it to their kernels.