[FREELDR] Change base address for NTLDR compatibility #7527
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| #define FREELDR_PE_BASE HEX(21000) | ||
| #define TEMPCODE_BASE HEX(200000) | ||
| #define TEMPCODE16_BASE HEX(7000) | ||
| #define MEMORY_MARGIN HEX(9FC00) /* We need this much memory */ |
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This will have to be changed back before the merge.
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Changing it back to HEX(88000) will limit freeldr to have 408KBs but i can change it to HEX(99000) because HEX(9FC00) is too big.
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| call ReadSectors | ||
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| mov dl, byte ptr [BootDrive] // Load boot drive into DL | ||
| mov dl, byte ptr fs:[BootDrive] // Load boot drive into DL |
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not intended change
| AddressOfRealModeEntryPoint: | ||
| .long 0 // receives address of RealModeEntryPoint | ||
| .word HEX(20)//RMODE_CS | ||
| .word L_RMODE_CS |
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What does that L_ prefix mean?
| /* Output status */ | ||
| mov si, offset Msg_SwitchToLongMode | ||
| call writestr | ||
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| /* Get flags CF, ZF and SF from the REGS structure */ | ||
| mov ax, word ptr cs:[BSS_RegisterSet + REGS_EFLAGS] | ||
| mov ax, word ptr ss:[BSS_RegisterSet + REGS_EFLAGS] |
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I'd prefer using es instead of ss (which looks weird).
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i will if possible
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Naive question: why would ES be preferrable ?
| .word HEX(9E00) | ||
| .word HEX(0000) | ||
| .word HEX(9B00) | ||
| .word HEX(008F) |
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The 16 bits flat CS is necessary because we need 21 bits instruction pointer on > 0xffff base address
| #define FREELDR_BASE HEX(20000) | ||
| #define FREELDR_PE_BASE HEX(30000) |
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64k padding? Why not 0x21000? Or does the base have to be 64k aligned?
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Using 64k unaligned base address make freeldr_pe.exe fail to generate on MSVC
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Purpose
This PR has the same purpose as #7501 but it changes the base address instead of "that relocation haxxory".
JIRA issue: CORE-19882
Warning
This PR is paused because of #7530
TODO