Displaying 4 results from an estimated 4 matches for "jcxz".
2017 Mar 24
0
"isolinux.bin missing or corrupt" when booting USB flash drive in old PC
...This gets pushed to the stack.
(So the code around the int 13 assumes that either int 13 fails and returns
CX == 0, or the reply is good enough to reach "andw 1,%cx". Ewww ...)
Now in isolinux.asm we have this test, quite immediately after the
stack was exploited:
mov si,bios_cbios
jcxz _start_common
mov si,bios_ebios
jmp _start_common
If CX is 4 (= EDD) here, then we go to LBA addressing and the confused
geometry is not of interest on the first try. At least this would explain
why our modern virtual BIOSes let isolinux.bin work. (I.e. the "EBIOS"
flag is indeed eff...
2017 Mar 24
2
"isolinux.bin missing or corrupt" when booting USB flash drive in old PC
Hi,
i am looking now at the code which i assume loads the rest of isolinux.bin.
The entry point for program execution from the MBR is obviously at
http://git.zytor.com/syslinux/syslinux.git/tree/core/isolinux.asm#n186
(Do i get it right that this is the Intel syntax ? (Gronfff))
If POP yields the victim of the most recent not yet popped PUSH, then
this does not look correctly coordinated
2010 Jun 21
2
[LLVMdev] MC: Object file specific parsing
...ncoded in 32-bit mode");
else if (Name == "pushfq")
- return Error(NameLoc, "pushfq cannot be encoded in 32-bit mode");
+ return Parser->Error(NameLoc, "pushfq cannot be encoded in 32-bit mode");
}
// The "Jump if rCX Zero" form jcxz is not allowed in 64-bit mode and
// the form jrcxz is not allowed in 32-bit mode.
if (Is64Bit) {
if (Name == "jcxz")
- return Error(NameLoc, "jcxz cannot be encoded in 64-bit mode");
+ return Parser->Error(NameLoc, "jcxz cannot be encoded in 64-bit...
2006 Mar 10
2
unload memdisk+FreeDOS => local boot
Sensei H. Peter Anvin,
I have successfully modified/enhanced memdisk so that one can chainload a
local operating system after running diskless FreeDOS.
I would like your advice regarding the appropriate interface for invoking
this functionality.
In addition, I would like to know what steps to take so that you feel
comfortable considering including this in the standard syslinux
distribution.