On 11/24/2015 04:39 PM, Andrew Morton wrote: > mips, powerpc and s390 also implement arch_mmap_rnd(). Are there any > special considerations here, or it just a matter of maintainers wiring > it up and testing it? I had not yet looked at those at all, as I had no way to do even a rudimentary "does it boot" test and opted to post v3 first. Upon first glance, it should just be a matter of wiring it up: Mips is divided into 12/16 bits for 32/64 bit (assume baseline 4k page) w/COMPAT kconfig, powerpc is 11/18 w/COMPAT, s390 is 11/11 w/COMPAT. s390 is a bit strange as COMPAT is for a 31-bit address space, although is_32bit_task() is used to determine which mask to use, and the mask itself for 64-bit only introduces 11 bits of entropy, but while still affecting larger chunks of the address space (mask is 0x3ff80, resulting in an effective 0x7ff shift of PAGE_SIZE + 7 bits). I could go ahead and add these to patchset v4 and as with the previous architectures, rely on feedback from arch-specific maintainers to help tune and test the values. -Dan -- 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>