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 <20220130211838.8382-26-rick.p.edgecombe@intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
Subject: Re: [PATCH 25/35] x86/cet/shstk: Add user-mode shadow stack support
In-Reply-To: <20220130211838.8382-26-rick.p.edgecombe@intel.com>
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On 1/30/22 13:18, Rick Edgecombe wrote:
> Add the user shadow stack MSRs to the xsave helpers, so they can be used
> to implement the functionality.

Do these MSRs ever affect kernel-mode operation?

If so, we might need to switch them more aggressively at context-switch
time like PKRU.

If not, they can continue to be context-switched with the PASID state
which does not affect kernel-mode operation.

Either way, it would be nice to have some changelog material to that effect.