At 07:35 PM 8/9/2006 +0200, you wrote: > > I didn't know if you were still working on it or whether it was just an > > example patch. If an example, it wasn't worth your time (or mine, > frankly) > > to go into further detail. If you're interested, the removal of the > 16-bit > > stack check and adjustment for PM_Entry "appears" to expose certain > > applications to a crash condition on a DE0CH value because of its use of > > ESP contents, potentially with a garbage value in the high word. > >The VCPI specs explicitely states that the pointer to the IRETD frame has to >be passed in SS:ESP. That means it's irrelevant if the VCPI client has >installed a 16-bit stack. In such a case it must ensure that Hiword(ESP) is >cleared before calling the host's entry with ax=de0ch. > >If you can tell us one of the "certain" applications ... :)
Would you feel better if I said "potential incompatibility" other than "possible bug"? Consider it done. The details of the spec negate a "bug" designation there. I do think it is inviting trouble not to set to a known state, since the original code was conceived and tested to clear up an existing problem, and was tested in that form. Is there a handy list of DOS applications which violate the full VCPI or XMS or EMS spec? No, although it's clear that a great many do. Even drivers themselves are guilty; all memory managers -- certainly including FreeDOS -- fail or fall short of full API support. Always a trade-off of available resources and user need. On a more general note, over a span of several years, I cannot reply to what application triggered what code response: I've tested hundreds. You may be correct that there is no application with a fault which triggers following the change in stack location. But at a minimum it's cheap insurance and removing it now cannot be guaranteed to work in the universe of applications -- including a large body of those already tested for FreeDOS. I think it bad timing to optimize with side-effects that could cause failure for a general distribution, but as I previously said, for personal use code, optimizations are great. ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Freedos-devel mailing list Freedos-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-devel
