On 29.11.2021 16:33, Roger Pau Monne wrote: > Introduce a helper based on the current Xen guest_cpuid code in order > to fetch a cpuid leaf from a policy. The newly introduced function in > cpuid.c should not be directly called and instead the provided > x86_cpuid_get_leaf macro should be used that will properly deal with > const and non-const inputs. > > Also add a test to check that the introduced helper doesn't go over > the bounds of the policy. > > Note the code in x86_cpuid_copy_from_buffer is not switched to use the > new function because of the boundary checks against the max fields of > the policy, which might not be properly set at the point where > x86_cpuid_copy_from_buffer get called, for example when filling an > empty policy from scratch. > > Suggested-by: Andrew Cooper <andrew.coop...@citrix.com> > Signed-off-by: Roger Pau Monné <roger....@citrix.com>
Reviewed-by: Jan Beulich <jbeul...@suse.com> > --- > Regarding safety of the usage of array_access_nospec to obtain a > pointer to an element of an array, there are already other instances > of this usage, for example in viridian_time_wrmsr, so I would assume > this is fine. I wonder what it is that you think one might be concerned about. Such pointer retrieval is no different from an actual array access imo. Jan
