Messages in this thread | | | Date | Tue, 7 Apr 2020 16:35:43 +0200 | From | Greg KH <> | Subject | Re: [PATCH 3/4] x86,module: Detect VMX vs SLD conflicts |
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On Tue, Apr 07, 2020 at 01:02:39PM +0200, Peter Zijlstra wrote: > It turns out that with Split-Lock-Detect enabled (default) any VMX > hypervisor needs at least a little modification in order to not blindly > inject the #AC into the guest without the guest being ready for it. > > Since there is no telling which module implements a hypervisor, scan > all out-of-tree modules' text and look for VMX instructions and refuse > to load it when SLD is enabled (default) and the module isn't marked > 'sld_safe'. > > Hypervisors, which have been modified and are known to work correctly, > can add: > > MODULE_INFO(sld_safe, "Y"); > > to explicitly tell the module loader they're good.
What's to keep any out-of-tree module from adding this same module info "flag" and just lie about it? Isn't that what you are trying to catch here, or is it a case of, "if you lie, your code will break" as well?
thanks,
greg k-h
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