[comboot] Propagate carry flag from COMBOOT API

COMBOOT API calls set the carry flag on failure.  This was not being
propagated because the COMBOOT interrupt handler used iret to return
with EFLAGS restored from the stack.  This patch propagates CF before
returning from the interrupt.

Reported-by: Geoff Lywood <glywood@vmware.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Marty Connor <mdc@etherboot.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
This commit is contained in:
Stefan Hajnoczi
2010-05-08 11:49:09 +01:00
committed by Michael Brown
parent 4fb3dae14e
commit 0d108681ac
3 changed files with 41 additions and 12 deletions

View File

@@ -669,6 +669,7 @@ void hook_comboot_interrupts ( ) {
"pushw %%cs\n\t"
"call prot_call\n\t"
"addw $4, %%sp\n\t"
"call patch_cf\n\t"
"iret\n\t" )
: : "i" ( int20 ) );
@@ -681,6 +682,7 @@ void hook_comboot_interrupts ( ) {
"pushw %%cs\n\t"
"call prot_call\n\t"
"addw $4, %%sp\n\t"
"call patch_cf\n\t"
"iret\n\t" )
: : "i" ( int21 ) );
@@ -693,6 +695,7 @@ void hook_comboot_interrupts ( ) {
"pushw %%cs\n\t"
"call prot_call\n\t"
"addw $4, %%sp\n\t"
"call patch_cf\n\t"
"iret\n\t" )
: : "i" ( int22) );