Re: [PATCH v2] x86/shstk: Provide kernel command line knob to disable

[Mathias Krause]

On 08.05.26 18:35, Edgecombe, Rick P wrote:
> On Fri, 2026-05-08 at 09:23 +0200, Mathias Krause wrote:
>>> Now that KVM uses this this feature independently of X86_FEATURE_USER_SHSTK,
>>> it might be good to have the plain HW shstk feature exposed for just normal
>>> runtime user use. (+Chao, for KVM CET)
>>
>> But that sounds more like having the need for an official chicken bit,
>> like I was proposing, no? Using 'clearcpuid=shstk' as a workaround for
>> whatever KVM bugs, similar in spirit to 'nousershstk', but without the
>> kernel taint?
> 
> For users to turn off shadow stack for guests? You can do this via the KVM API
> in the normal way you customize guests.

https://git.kernel.org/linus/2d5d3fc593c9b7e41bee86175d7b9e11f470072e

Oh, well....