Message-Id: <3.0.1.16.19970502131254.2f47a584@mailhost.sm.ic.ac.uk>
Date: Fri, 02 May 1997 13:12:54
To: djgpp AT delorie DOT com, steve AT cis DOT plym DOT ac DOT uk
From: Paul Dixon <p DOT dixon AT ic DOT ac DOT uk>
Subject: Re: Crash under NT DOS shell
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>What does ntvdm!GetMSW do?  Any ideas as to what might cause ntvdm to
>fall over at this
>location?  It's being a pig to track down as the DOS shell text output
>doesn't keep up with 
>cout, so the crash can stop the process *before* tracing comments get
>written to the screen!

Not sure, but I would be surprised if getMSW didnt stand for Get Machine
Status Word - the function is attempting to retrieve several long ints from
an internal structure and return, but the memory for return (in segment 
es == 0x1cf) is not valid and so the process causes a memory fault

Hope this helps (but guess it probably doesnt...)

>function: getMSW
>        0fed1282 8983c40a0000     mov     [ebx+0xac4],eax       
>ds:0ff60f54=00000206
>        0fed1288 8b83980b0000     mov     eax,[ebx+0xb98]       
>ds:0ff61028=000001cf
>        0fed128e 8ec0             mov     es,eax
>        0fed1290 8bbb940b0000     mov     edi,[ebx+0xb94]       
>ds:0ff61024=00135fb0
>        0fed1296 0f02c0           lar     eax,eax
>        0fed1299 a900004000       test    eax,0x400000
>        0fed129e 7503             jnz     getMSW+0x136 (0fed12a3)
>        0fed12a0 0fb7ff           movzx   edi,di
>        0fed12a3 8b83900b0000     mov     eax,[ebx+0xb90]       
>ds:0ff61020=00010202
>        0fed12a9 83ef04           sub     edi,0x4
>FAULT ->0fed12ac 268907           mov     es:[edi],eax          
>es:00135fac=????????
>        0fed12af 8b838c0b0000     mov     eax,[ebx+0xb8c]       
>ds:0ff6101c=000001c7
>        0fed12b5 83ef04           sub     edi,0x4
>        0fed12b8 268907           mov     es:[edi],eax          
>es:00135fac=????????
>        0fed12bb 8b83880b0000     mov     eax,[ebx+0xb88]       
>ds:0ff61018=00013cb0
>        0fed12c1 83ef04           sub     edi,0x4
>        0fed12c4 268907           mov     es:[edi],eax          
>es:00135fac=????????
>        0fed12c7 83ef04           sub     edi,0x4
>        0fed12ca 8b83840b0000     mov     eax,[ebx+0xb84]       
>ds:0ff61014=00135fbc
>        0fed12d0 268907           mov     es:[edi],eax          
>es:00135fac=????????
>        0fed12d3 06               push    es
>        0fed12d4 57               push    edi

---------------------------------------------------------------------
Paul Dixon                            
Software Engineer, Dept of Paediatrics  Telephone: (+44) 171 725 1098
St Mary's Hospital Medical School       Fax:       (+44) 171 725 6284
Norfolk Place, London W2 1PG, UK        Email:       p DOT dixon AT ic DOT ac DOT uk

A Constituent College of 
                 Imperial College of Science, Technology and Medicine
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