>>> >From that perspective, the dependency on X86 is awful. What's the >>> problem here and what do other architectures need to do to be able to >>> support the feature? >> >> The problem here is that I don't know what free bits are available on >> page table entries on other architectures. I was about to resolve this >> for ARM very soon, but for the rest of them I need help from other people. > > Well, this is also a thing arch maintainers can do when they feel a > need to support the feature on their architecture. To support them at > that time we should provide them with a) adequate information in an > easy-to-find place (eg, a nice comment at the site of the reference x86 > implementation) and b) a userspace test app. Item a) is presumably covered with two things -- required arch-specific PTE manipulations are all collected in asm-generic/pgtable.h under the !CONFIG_HAVE_ARCH_SOFT_DIRTY and the Documentation/vm/soft-dirty.txt pointed by the API clear_refs_soft_dirty()'s comment. Item b) was recently merged. Item c) from Stephen is already sent. Thank you for your time and help, Pavel -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>