isolinux: bsHidden can't be in data; it is set before checksumming

We cannot put bsHidden in initializated data, as it is set before we
run the global checksumming.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/core/isolinux.asm b/core/isolinux.asm
index fd18bd3..38d3d71 100644 (file)
--- a/core/isolinux.asm
+++ b/core/isolinux.asm
@@ -108,20 +108,23 @@ GetlinsecPtr      resw 1                  ; The sector-read pointer
 BIOSName       resw 1                  ; Display string for BIOS type
 %define HAVE_BIOSNAME 1
 BIOSType       resw 1
-bsSecPerTrack  resw 1                  ; Used in hybrid mode
-bsHeads                resw 1                  ; Used in hybrid mode
 DiskError      resb 1                  ; Error code for disk I/O
 DriveNumber    resb 1                  ; CD-ROM BIOS drive number
 ISOFlags       resb 1                  ; Flags for ISO directory search
 RetryCount      resb 1                 ; Used for disk access retries
 
-_spec_start    equ $
+               alignb 8
+bsHidden       resq 1                  ; Used in hybrid mode
+bsSecPerTrack  resw 1                  ; Used in hybrid mode
+bsHeads                resw 1                  ; Used in hybrid mode
+
 
 ;
 ; El Torito spec packet
 ;
 
                alignb 8
+_spec_start    equ $
 spec_packet:   resb 1                          ; Size of packet
 sp_media:      resb 1                          ; Media type
 sp_drive:      resb 1                          ; Drive number
@@ -245,11 +248,15 @@ _start_hybrid:
                pop dx
                pop di
                pop es
+               xor eax,eax
+               xor edx,edx
                cmp sp,7C00h
                jae .nooffset
-               pop dword [cs:bsHidden]
-               pop dword [cs:bsHidden+4]
+               pop eax
+               pop edx
 .nooffset:
+               mov [cs:bsHidden],eax
+               mov [cs:bsHidden+4],edx
 
                mov si,bios_cbios
                jcxz _start_common
@@ -1066,9 +1073,7 @@ bios_cbios_str    db 'CHDD', 0
 bios_ebios_str db 'EHDD' ,0
 %endif
 
-               alignz 8
-bsHidden       dq 0                            ; Used in hybrid mode
-
+               alignz 4
 bios_cdrom:    dw getlinsec_cdrom, bios_cdrom_str
 %ifndef DEBUG_MESSAGES
 bios_cbios:    dw getlinsec_cbios, bios_cbios_str