[Babel-users] sending rtt always on 1.8?

[Juliusz Chroboczek]

> in glibc at least it's a read from a universally shared page - taking
> ns - rather than a syscall.

On x86.  Other arches may differ.

> Is it really a 4.5 issue? (got link?).

Sorry, I was mistaken, it's 4.4:

  https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=a7f4df4e21dd8a8dab96e88acd2c9c5017b83fc6

> I thought openwrt was shipping 4.4, also.

Depends on the board.  It's claimed that 4.4 will be supported on all
boards for DD, we'll see how that goes.  CC uses 3.18.23.

> Is it possibly an arm issue (most of what I'm working on is arm)?

ARM has gained support in 4.1, according to the vdso(7) manual page.  No
idea if it's being used by musl.

-- Juliusz