Re: [RFC v2 08/32] x86/traps: Add #VE support for TDX guest

From: Andi Kleen
Date: Tue Jun 08 2021 - 14:18:12 EST



On 6/8/2021 11:15 AM, Dave Hansen wrote:
On 6/8/21 11:12 AM, Andi Kleen wrote:
I believe neither does mmio/msr normally (except maybe
ftrace+tp_printk, but that will likely work because it shouldn't
recurse more than once due to ftrace's reentry protection)
Can it do MMIO:

+DEFINE_IDTENTRY(exc_virtualization_exception)
+{
=======> HERE
+ ret = tdg_get_ve_info(&ve);
Recursion isn't the problem. It would double-fault there, right?

Yes that's right. tp_printk already has a lot of other corner cases that break though, so it's not a real issue.

-Andi