Re: [RFD] x86/split_lock: Request to Intel

From: Peter Zijlstra
Date: Fri Oct 18 2019 - 06:43:27 EST


On Fri, Oct 18, 2019 at 06:20:44PM +0800, Xiaoyao Li wrote:

> We enable #AC on all cores/threads to detect split lock.
> -If user space causes #AC, sending SIGBUS to it.
> -If kernel causes #AC, we globally disable #AC on all cores/threads,
> letting kernel go on working and WARN. (only disabling #AC on the thread
> generates it just doesn't help, since the buggy kernel code is possible to
> run on any threads and thus disabling #AC on all of them)
>
> As described above, either enabled globally or disabled globally, so whether
> it's per-core or per-thread really doesn't matter

Go back and read the friggin' thread already. A big clue: virt ruins it
(like it tends to do).