Re: [PATCH] x86/asm/entry/32: Restore %ss before SYSRETL if necessary

[Linus Torvalds]

On Thu, Apr 23, 2015 at 9:06 AM, Brian Gerst <brgerst@xxxxxxxxx> wrote:
>
> So you are saying we should save and conditionally restore the
> kernel's %ss during context switch?  That shouldn't be too bad.  Half
> of the time you would be loading the null selector which is fast (no
> GDT access, no validation).

I'd almost prefer something along those lines, yes. Who knows *what*
leaks? If the present bit state leaks, then likely so does the limit
value etc etc..

                         Linus
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