Re: [patch 20/24] x86/speculation: Split out TIF update

[Jiri Kosina]

On Tue, 27 Nov 2018, Thomas Gleixner wrote:

> That's racy and does not prevent the situation because the TIF flags are
> updated befor the UPDATE bit is set. 

> So __speculation_ctrl_update() might see the new bits, but not 
> TIF_SPEC_UPDATE. 

Hm, right, scratch that. We'd need to do that before updating TIF_SPEC_IB 
in task_update_spec_tif(), but that has the opposite ordering issue.

Thanks,

-- 
Jiri Kosina
SUSE Labs