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POPAD.MSG
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1993-06-18
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6KB
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103 lines
JP>Has anyone heard of bugs on the 386 series? Has anyone used
JP>386POPAD to test their system, if so what were the results?
DMW>
DMW> There are two bugs that I know of:
DMW>
DMW> 1. POPAD bug. Most 386 processors have this bug. Intel corrected it in
DMW> the later revisions of its 386. All AMD 386 processors have the bug,
DMW> as far as I know.
DMW>
DMW> The POPAD bug is a bit of a misnomer, and is hardly ever a problem.
DMW> If the instruction POPA or POPAD is followed by certain MOV
DMW> instructions, the AX or EAX register (respectively) will contain
DMW> zero. Most programmers only use POPA/POPAD at the end of a
DMW> subroutine; therefore, it is usually followed by a RET instruction.
DMW> This will not invoke the bug. In addition, most programmers know
DMW> about this bug, and will not code routines that invoke it.
DMW>
DMW> 2. MUL bug. I have never seen this bug personally, but it's rumored
DMW> that some very old Intel 386 processors will return unpredictable
DMW> results when 32-bit operands are used with the MUL instruction. AMD
DMW> 386 processors do not have this bug.
DMW>
DMW> 3. POPCS bug. This is not really a bug, but I included it here for
DMW> completeness. Some ill-behaved software uses the "POP CS"
DMW> instruction. Intel lists this instruction as invalid, but it works
DMW> on the 8088/8086. 286 and higher processors use this instruction
DMW> (0Fh) as a prefix for their extended instructions, and will produce
DMW> unexpected results if used as a "POP CS". I've only heard of one
DMW> program that uses this instruction. It is one of the older viruses,
DMW> and it did not spread very well due to the fact that it crashed 286+
DMW> machines.
DMW>
DMW> The following is a DEBUG script that will produce CPUBUGS.ARJ. This
DMW> archive contains three programs. Each will test for one of the above
DMW> bugs.
DMW>
DMW> N CPUBUGS.ARJ
DMW> E 0100 60 EA 2B 00 1E 05 01 00 10 00 02 F9 F9 90 D0 1A
DMW> E 0110 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
DMW> E 0120 00 00 43 50 55 42 55 47 53 2E 41 52 4A 00 00 7E
DMW> E 0130 B9 AE EA 00 00 60 EA 2C 00 1E 05 01 00 10 01 00
DMW> E 0140 F9 4C 8E D0 1A 76 00 00 00 A2 00 00 00 C2 50 D6
DMW> E 0150 E0 00 00 20 00 00 00 50 4F 50 41 44 33 38 36 2E
DMW> E 0160 43 4F 4D 00 00 26 78 35 5F 00 00 00 57 53 53 8D
DMW> E 0170 38 8D 62 0E CC 70 2E 26 B2 26 51 68 1A 4C 23 35
DMW> E 0180 A0 69 86 AB 25 FA 1B 19 B3 A4 4F FE 08 60 28 16
DMW> E 0190 5C 75 0B 70 2F 13 6A 0A 0A 02 76 00 65 07 D2 47
DMW> E 01A0 00 FE 07 67 E0 D5 02 82 E0 60 D3 CC 0F 2F 9E A9
DMW> E 01B0 B2 9D F6 CC DE 30 AE 32 07 FB 8D 52 AE 1E 07 8A
DMW> E 01C0 86 4A CF 45 7C 23 6D 85 64 4A 13 D3 A9 6F F6 C2
DMW> E 01D0 E3 E5 7E 97 86 5C A8 B3 51 F6 47 7D 8F BC AD E4
DMW> E 01E0 80 60 EA 2B 00 1E 05 01 00 10 01 00 F9 6B 8E D0
DMW> E 01F0 1A C7 01 00 00 12 04 00 00 8D 54 0B 31 00 00 20
DMW> E 0200 00 00 00 4D 55 4C 54 45 53 54 2E 45 58 45 00 00
DMW> E 0210 02 E9 2F D4 00 00 01 97 62 7B D6 36 BF DF FA EE
DMW> E 0220 5D 9A 15 B8 60 3A 12 9F DA 55 80 8B 4C 98 11 5D
DMW> E 0230 9C 15 4C 82 37 3A EB 6E 0D B6 81 8E D6 FB BA F2
DMW> E 0240 75 EE C7 7B DC E0 61 56 2D 51 95 70 2C D4 C8 73
DMW> E 0250 61 29 4D 01 81 41 61 2C 6A A1 B8 18 38 60 6D 81
DMW> E 0260 C9 DF F7 70 D8 2C 06 2B F2 41 F8 56 A9 8C DD 4A
DMW> E 0270 6C FD 5E 60 62 01 80 42 80 41 04 D0 05 00 2C 80
DMW> E 0280 06 69 7D 30 7E 32 7C 2E 07 F6 34 1F F9 FE 8B 79
DMW> E 0290 79 F3 4C B7 A7 A2 65 B8 7E 8B 65 F3 7A 46 77 15
DMW> E 02A0 6C BE 4C F3 27 90 F1 83 ED 88 F0 05 ED 1C AF 7B
DMW> E 02B0 FF 28 3B 46 04 C8 C1 C1 A9 7B 47 D8 A0 7A B1 B7
DMW> E 02C0 24 5F 99 83 8B 52 DE EF B5 F5 1F C8 0B 7B B3 A5
DMW> E 02D0 BF 8E 16 FD D0 ED 8C 57 2D 8C 17 94 C9 CC EC 78
DMW> E 02E0 A4 29 8B 6F E1 08 FB CF 72 C3 CF F3 BA 01 B9 CA
DMW> E 02F0 BF 32 E6 AD CD 6B 5B D2 EA 6D DC D3 B5 F5 DF B5
DMW> E 0300 C7 BE 9E AB D0 41 4A 3D 93 D0 A7 B7 77 D7 10 72
DMW> E 0310 7C F3 40 FF 8E 27 FE 75 07 7E F7 7E 31 79 9E 0A
DMW> E 0320 37 E6 10 45 E3 D6 02 D6 EF E6 3C CC 59 E1 EB F9
DMW> E 0330 FA 54 6A E7 54 AA 3D 41 AB 61 84 0E CB 8D AE E2
DMW> E 0340 B6 47 69 86 59 1A E7 49 DC B2 C3 47 1D AB 07 4D
DMW> E 0350 83 B8 25 49 52 47 0C EE 52 D2 12 28 AA CB 32 C5
DMW> E 0360 64 9E B9 16 4D 88 42 0C DC AE BF 58 49 6C 76 1D
DMW> E 0370 5E 6C A9 33 B3 A9 D3 D0 A7 D9 FD B1 96 55 CE 86
DMW> E 0380 17 68 8C 25 B1 D8 38 B8 EB 42 DB 42 AE 16 38 51
DMW> E 0390 6B 32 AA 22 29 58 E8 43 6E 4C 24 DA A7 42 58 69
DMW> E 03A0 7E 98 EC B2 75 50 5C 79 56 13 3E 7C FD 72 93 A5
DMW> E 03B0 49 FD 32 46 3C 52 43 10 3A 1D F1 CC ED BA B8 F8
DMW> E 03C0 1B 48 D2 70 E8 3B 49 CD FE 0B EE D0 EF 51 A9 18
DMW> E 03D0 8C 21 3C 90 FE 4D E8 C8 52 44 57 DE 96 60 EA 29
DMW> E 03E0 00 1E 05 01 00 10 00 00 F9 E9 90 D0 1A 58 00 00
DMW> E 03F0 00 58 00 00 00 58 D8 DE 42 00 00 20 00 00 00 50
DMW> E 0400 4F 50 43 53 2E 43 4F 4D 00 00 C7 F3 87 27 00 00
DMW> E 0410 BA 2A 01 B4 09 CD 21 8B EC 0E BB 70 00 0F 98 47
DMW> E 0420 90 3B EC 74 07 BA 36 01 B4 09 CD 21 8B E5 BA 3B
DMW> E 0430 01 B4 09 CD 21 B8 00 4C CD 21 22 50 4F 50 20 43
DMW> E 0440 53 22 20 69 73 24 20 4E 4F 54 24 20 73 75 70 70
DMW> E 0450 6F 72 74 65 64 20 6F 6E 20 74 68 69 73 20 70 72
DMW> E 0460 6F 63 65 73 73 6F 72 24 60 EA 00 00
DMW> RCX
DMW> 036C
DMW> W
DMW> Q
DMW>
DMW> * SLMR 2.1 * Move over Rover and let Jimi take over...
DMW>
DMW> === Maximus 2.01wb
DMW> * Origin: The Southern Star - 6 Lines - HST/V32b - 504-885-5928 - (1:396/1)