Hi Christoph, On Fri, May 1, 2020 at 1:46 AM Christoph Hellwig <h...@infradead.org> wrote: > any idea why xtensa uses PAGE_KERNEL_EXEC instead of PAGE_KERNEL > for kmap_prot? Mapping all mapped highmem as executable seems rather > dangerous.
I sure do: to allow instruction cache flushing when writing to high user pages temporarily mapped with kmap. Instruction cache management opcodes that operate on virtual addresses would raise an exception if the address is not executable. -- Thanks. -- Max
