On 2/12/19 15:11, Jan Beulich wrote: >>>> On 08.02.19 at 14:44, <nmant...@amazon.de> wrote: >> Checks of domain properties, such as is_hardware_domain or is_hvm_domain, >> might be bypassed by speculatively executing these instructions. A reason >> for bypassing these checks is that these macros access the domain >> structure via a pointer, and check a certain field. Since this memory >> access is slow, the CPU assumes a returned value and continues the >> execution. >> >> In case an is_control_domain check is bypassed, for example during a >> hypercall, data that should only be accessible by the control domain could >> be loaded into the cache. >> >> Signed-off-by: Norbert Manthey <nmant...@amazon.de> >> >> --- >> >> Notes: >> v6: Drop nospec.h include > And this was because of what? I think it is good practice to include > other headers which added definitions rely on, even if in practice > _right now_ that header gets included already by other means. If > there's some recursion in header dependencies, then it would have > been nice if you had pointed out the actual issue.
The nospec.h header has been introduced by the commit "xen/sched: Introduce domain_vcpu() helper" between my v4 and v6, so I had to drop my include there. The sched.h file still includes the nospec.h file, I just do not have to add it any more. I could have been a bit more verbose in the notes section. Best, Norbert > > Jan > > Amazon Development Center Germany GmbH Krausenstr. 38 10117 Berlin Geschaeftsfuehrer: Christian Schlaeger, Ralf Herbrich Ust-ID: DE 289 237 879 Eingetragen am Amtsgericht Charlottenburg HRB 149173 B _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
