At 09:20 AM 8/17/2006 +0200, tom ehlert wrote: > >> May you explain here and/or, better, in comments in source, why > >> decreasing SP solves issues (and which issues there are)? >>Only > >> plausible explanation: >>THIS BIOS damages (sometimes ?) the > >> flags; Do you mean "flags, _saved on the stack above given code_"? > >> And, if so, then why flags are damaged, but return value, which was lies > >> on place of flags (relative SP) are not damaged, if you comment out > "pushf"? >that's all I know. this ugly patch solves the issue. >looks like sometimes someone damages something on the stack, which >goes unnoticed most of the time > > > Could just be hitting one word on the stack, i.e. [sp] at INT entry. That > > would match the behavior on either of the two patches. >right > > > However, there's something suspicious about the fact that this is happening > > in INT 15h, and INT 15h is one of the places where EMM386 code where INT > > handling was recently changed >there's no EMM386 involved in that case (it's not loaded)
Okay, so with EMM386 out, we're pretty definitely looking at a BIOS bug. I guess I'll use your SUB SP patch and move the A20 BIOS check to second from last in line. That will avoid the BIOS issue for most situations, and hopefully work around the bug for anything which gets that far. Plus, I just found out that there exist old compressed DOS programs which avoid the automatic A20 handling of the kernel, and try to directly use address wrapping, so there's no way to automatically avoid the "packed file is corrupt" termination with high free memory In other words, those old programs must use LOADFIX or other workarounds to run. I'm still waiting for some good news to come in. ------------------------------------------------------------------------- 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
