Messages in this thread | | | Date | Thu, 3 Aug 2023 15:12:07 +0300 | From | "" <> | Subject | Re: [PATCH v3 07/12] x86/tdx: Make TDX_HYPERCALL asm similar to TDX_MODULE_CALL |
| |
On Thu, Aug 03, 2023 at 11:56:40AM +0000, Huang, Kai wrote: > On Thu, 2023-08-03 at 14:45 +0300, kirill.shutemov@linux.intel.com wrote: > > > > I would rather keep the struct > > > > read-only where possible. > > > > > > > > > > We can achieve this if there's a clean way to do, but I don't see that. > > > > Keep _ret() and non-_ret() versions? > > The problem is the assembly needs to always turn on the "\ret" so that the R10 > (used as VP.VMCALL leaf return code) can be saved to the structure. Otherwise > we are not able to return VP.VMCALL leaf return code.
Yeah. This is downside of single assembly macro for all calls.
One possible way is to make it in C: non-_ret() version pass to the assembly helper copy of the caller's struct, keeping original intact. But, yeah, it is ugly.
-- Kiryl Shutsemau / Kirill A. Shutemov
| |