From: muta...@gmail.com   
      
   On Saturday, March 25, 2023 at 7:21:50 PM UTC+8, wolfgang kern wrote:   
      
   > >> why you don't get it: _I can't/wont use your files_    
   >    
   > > That's the first I've heard that. I thought the barrier    
   > > was creating a FAT USB stick and I thought we    
   > > were trying to solve that problem.    
   >    
   > >> I have only one working and eleven dead PCs here,    
   > >> and I need this one for posting and currently for games.    
   >    
   > > You can't afford a new computer so that you can do    
   > > experiments?   
      
   > I don't buy M$ prepared PCs, I bought one 1980, and I always assembled    
   > machines individual since then usually just to fit client's demand.    
   >    
   > [I don't have any problems with money :)]   
      
   Ok, it's still unclear to me what (artificial) constraints   
   you are placing, and why, but they are clearly genuine   
   constraints, and that is an interesting use case scenario.   
      
   > >> So you can do this tests and report what you found.    
   >    
   > > If you give me a specific instruction to test (ie something    
   > > that will assemble with the mingw assembler), I can do so.   
      
   > dunno mingw, but it may be able to use "db HEX" like other ASM do.   
      
   I don't know how to do that. Rather than try to find out,   
   I simply tried the mnemonics.   
       
   > 33 C9 XOR ecx,ecx    
   > B1 1B MOV CL.0x1B ;make RCXX==0x1B (returns APIC_BASE on AMDs)    
   > 0F 32 RDMSR ;may crash if this MSR doesn't exist or CPL>0    
   >    
   > or an easier one:    
   >    
   > 0F 09 WBINV ;alters no registers crash if CPL>0.   
      
   I started with the easier one, but it didn't assemble.   
      
   But this one assembled:   
      
   .globl efimain   
   efimain:   
      
   # wbinv   
      
   xor ecx,ecx   
   mov cl, 0x1b   
   rdmsr   
      
   xxx: jmp xxx   
   #ret   
      
   And then executed either the loop or ret that followed, and   
   both of them perfomed as expected (ie identical to   
   previous).   
      
   > > But if you're reading the docs anyway, you'll    
   > > probably get the answer there.   
      
   > haven't found anything mentioned about start condition in these docs so    
   > far.   
      
   Ok. So reverse-engineering turned out to be easier.   
      
   BFN. Paul.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)