Changeset 84673 in vbox for trunk/src/VBox/Devices

Timestamp:

Jun 4, 2020 9:38:05 AM (5 years ago)

Author:

vboxsync

Message:

BIOS: Removed INT 19h heuristic altogether (see bugref:5649).

File:

• trunk/src/VBox/Devices/PC/BIOS/orgs.asm (modified) (1 diff)

trunk/src/VBox/Devices/PC/BIOS/orgs.asm

@@ -1587 +1587 @@
 ;;
 int19_relocated:
-; If an already booted OS calls int 0x19 to reboot, it is not sufficient
-; just to try booting from the configured drives. All BIOS variables and
-; interrupt vectors need to be reset, otherwise strange things may happen.
-; The approach used is faking a warm reboot (which just skips showing the
-; logo), which is a bit more than what we need, but hey, it's fast.
-;
-; Initially we checked if the caller is in the F000h segment, i.e. the
-; system BIOS. But option ROMs can also legitimately invoke INT 19h so
-; we need different heuristics.
-                xor     ax, ax
-                mov     ds, ax
-                mov     es, ax
-                cld
-                ; Check if the boot sector area is untouched
-                mov     cx, 256
-                mov     di, 7C00h
-                repe scasw
-                jcxz    bios_initiated_boot
-
-                mov     ax, 1234h
-                mov     ds:[472], ax
-                jmp     post
-
-bios_initiated_boot:
                 ;; The C worker function returns the boot drive in bl and
                 ;; the boot segment in ax. In case of failure, the boot