On Wed, Sep 23, 2020 at 07:16:08PM +0200, Paolo Bonzini wrote: > On 23/09/20 19:04, Sean Christopherson wrote: > >> Two of the three instances are a bit different though. What about this > >> which at least shortens the comment to 2 fewer lines: > > Any objection to changing those to "Flush (on non-coherent CPUs)"? I agree > > it would be helpful to call out the details, especially for DBG_*, but I > > don't like that it reads as if the flush is unconditional. > > Hmm... It's already fairly long lines so that would wrap to 3 lines, and Dang, I was hoping it would squeeze into 2. > the reference to the conditional flush wasn't there before either. Well, the flush wasn't conditional before (ignoring the NULL check). > sev_clflush_pages could be a better place to mention that (or perhaps > it's self-explanatory). I agree, but with /* * Flush before LAUNCH_UPDATE encrypts pages in place, in case the cache * contains the data that was written unencrypted. */ sev_clflush_pages(inpages, npages); there's nothing in the comment or code that even suggests sev_clflush_pages() is conditional, i.e. no reason for the reader to peek at the implemenation. What about: /* * Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in * place, the cache may contain data that was written unencrypted. */
