[Xen-devel] Re: [PATCH] rombios: move the stack to 0x9e000 and protect it with an e820 entry

[Tim Deegan <Tim.Deegan@xxxxxxxxxx>]

At 16:44 +0100 on 06 Jul (1278434642), Tim Deegan wrote:
> Ooops - please don't apply this, it breaks CD-ROM boot. 

Correction, please do apply it, and also this:

rombios: use explicit SS prefix for calculated on-stack array accesses.
The bcc compiler gets constant array offsets right but does all calculated
array offsets via DS.

Signed-off-by: Tim Deegan <Tim.Deegan@xxxxxxxxxx>

diff -r e316ad18de3c tools/firmware/rombios/rombios.c
--- a/tools/firmware/rombios/rombios.c  Wed Jul 07 11:27:36 2010 +0100
+++ b/tools/firmware/rombios/rombios.c  Wed Jul 07 11:30:14 2010 +0100
@@ -3735,10 +3735,10 @@
   // Validity checks
   if(buffer[0]!=0)return 4;
   for(i=0;i<5;i++){
-    if(buffer[1+i]!=read_byte(0xf000,&isotag[i]))return 5;
+    if(read_byte(get_SS(),&buffer[1+i])!=read_byte(0xf000,&isotag[i]))return 5;
    }
   for(i=0;i<23;i++)
-    if(buffer[7+i]!=read_byte(0xf000,&eltorito[i]))return 6;
+    if(read_byte(get_SS(),&buffer[7+i])!=read_byte(0xf000,&eltorito[i]))return 
6;
 
   // ok, now we calculate the Boot catalog address
   
lba=buffer[0x4A]*0x1000000+buffer[0x49]*0x10000+buffer[0x48]*0x100+buffer[0x47];

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel