Re: [PATCH v2 12/18] x86/espfix/64: Stop assuming that pt_regs is on the entry stack

[Thomas Gleixner]

On Tue, 21 Nov 2017, Andy Lutomirski wrote:

> When we start using an entry trampoline, a #GP from userspace will
> be delivered on the entry stack, not on the task stack.  Fix the
> espfix64 #DF fixup to set up #GP according to TSS.SP0, rather than
> assuming that pt_regs + 1 == SP0.  This won't change anything
> without an entry stack, but it will make the code continue to work
> when an entry stack is added.
> 
> Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>

Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>