On Mon, Dec 22, 2014 at 09:08:36AM -0800, Andrew Fish wrote: > > An issue has come up while developing the EFI support for the arm64 > > linux kernel, in particular the support for kexec which requires > > changes with respect to how we handle the virtual to physical mapping > > of runtime services. > > > > My question is: is it legal for SetVirtualAddressMap() [which is > > called using a 1:1 mapping as per the spec] to already dereference > > those virtual addresses before it returns itself? My assumption would > > be no, as it would require two mappings to be active at the same time, > > implying that those mappings should never overlap. However, the spec > > is not explicit about this in the text, > > It is hard for the spec to tell you what not to do as the surface are of that > is very large, the spec focus on telling you what is required.
But if the behaviour Ard is describing is permitted as per the spec, must the spec then not also state that all virtual mappings being requested are required to be present and active in the memory map? I can not find any instance stating this. Which can be interpreted as an implicit ban on touching the virtual mappings before SetVirtualAddressMap() returns. Or have I missed something? Regards, Leif ------------------------------------------------------------------------------ Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net _______________________________________________ edk2-devel mailing list edk2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/edk2-devel
