> This patch matches with "[PATCH v2] Enable CPU SMEP feature support for 
> QEMU-KVM", no changes since v1.
>
> Enable newly documented SMEP (Supervisor Mode Execution Protection) CPU 
> feature in KVM module.
>
> Intel new CPU supports SMEP (Supervisor Mode Execution Protection). SMEP 
> prevents kernel from executing code in application. Updated Intel SDM 
> describes this CPU feature. The document will be published soon.
>
> This patch is based on Fenghua's SMEP patch series, as referred by: 
> https://lkml.org/lkml/2011/5/17/523
> This patch enables guests' usage of SMEP.
> Currently, we don't enable this feature for guests with shadow page tables.

> Why not?  I see nothing that conflicts with shadow.

We don't need to enable it for shadow page table, because shadow has mask 
against guest/shadow PTE, which may cause problem.  Let's keep shadow as it is 
because it's already very complex. Assume SMEP machines should have EPT.

> Missing:
>   update kvm_set_cr4() to reject SMEP if it's disabled in cupid

Yes, I will check it.

>   drop SMEP from cr4_guest_owned_bits if SMEP is disabled in cupid

SMEP BIT is not included in KVM_CR4_GUEST_OWNED_BITS.

>   update walk_addr_generic() to fault if SMEP is enabled and fetching 

Comments above.

> from a user page

--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to